Which two layers of Earth are mainly composed of metallic elements such as nickel and iron, which are abundant in meteoroids and comets?

Answers

Answer 1
This layer of the earth lies between the mantle and the solid inner core. It is the only liquid layer, a sea of mostly iron and nickel about 1,400 miles. The lava is mostly made up of iron and nickel. The outer core creates the Earth's magnetic field. The final layer is the inner core, which is 900 miles deep. Scientists believe the inner core is a solid ball of iron and other minerals.
Answer 2

This layer of the earth lies between the mantle and the solid inner core. It is the only liquid layer, a sea of mostly iron and nickel about 1,400 miles. The lava is mostly made up of iron and nickel. The outer core creates the Earth's magnetic field. The final layer is the inner core, which is 900 miles deep. Scientists believe the inner core is a solid ball of iron and other minerals.


Related Questions

the transfer of a section of DNA from one organism into the DNA of another organism by scientists is called

Answers

I am going toward selective breeding however it can also be genetic engineering. 

The transfer  of a section of DNA from one organism into the DNA of another organism by scientists is called genetic engineering.

What is DNA?

DNA  is a hereditary material  which is present in human beings as well as all other living organisms.  Every cell which is present in an organism's body has DNA  which is the same. Most of the DNA is situated in the cell's nucleus and small amount of it can be found in the cell's mitochondria as well.

Information which is stored in DNA is stored as codes made up of four chemical bases namely, adenine, thymine , cytosine and guanine.Human DNA consists of 3 billion bases .The order of the bases determines information which is required for building and maintaining an organism.

DNA bases are capable of pairing up with each other. Adenine pairs with thymine and guanine pairs up with cytosine .Each base is also attached to a sugar molecule  and a phosphate group. A base, phosphate  sugar are together called as nucleotides.

Learn more about DNA,here:

https://brainly.com/question/28481425

#SPJ2

Write the balanced nuclear equation for β− decay of sodium−26. include both the mass numbers and the atomic numbers with each nuclear symbol. use the sup-subscript button in the answer palette to enter these numbers correctly. greek letters can be accessed in the drop-down menu that says -select−.

Answers

β- decay is the emission of an electron by converting a neutron into a proton.

After doing β- decay, the formed daughter nucleus has the same number of mass number as the parent atom but the atomic number has increased by 1 and neutron number has reduced by 1.

If Na²⁶₁₁ (number of neutrons = 26 - 11 = 15) undergoes a β- decay, then produced daughter atom must have 12 protons and 14 neutrons. Hence, the daughter atom should be Mg.

Na²⁶₁₁ → Mg²⁶₁₂ + ₋₁⁰β + energy

The balanced nuclear equation for beta decay of sodium-26 is represented as Na²⁶₁₁ → Mg²⁶₁₂ + β₋₁⁰ + energy.

What is beta decay?

Beta decay is one of the type of radioactive nuclear decay reaction in which emission of a beta particle takes place from the atomic nuclear.

Beta particle define by the symbol β₋₁⁰ i.e. this particles has no mass but having a negative charge on it. In this reaction atomic mass of the parent atom is equal to the new formed daughter atom. But in this reaction number of neutron is reduced by 1 and number of proton is increased by one of parent atom. So, balanced nuclear equation for β− decay of sodium−26 is represnted as:

Na²⁶₁₁ → Mg²⁶₁₂ + β₋₁⁰ + energy

Hence balanced nuclear equation for the beta decay is represented above.

To know more about beta decay, visit the below link:

https://brainly.com/question/13174032

Which of the temperatures below is most likely to be the boiling point of water at 880 torr?view available hint(s)which of the temperatures below is most likely to be the boiling point of water at 880 torr?92°c105°c100°c?

Answers

Boiling point  is the temperature at which the vapor pressure of the liquid equals the surrounding pressure.

Above boiling point point, liquid get converted into vapour.

Now, boiling point of water is 100 oC at room pressure. Room pressure is equal to 760 torr. Thus, at 100 oC, vapour pressure of water becomes equal to 760 torr.

Now, if external pressure is increased to 880 torr, more heat is to be supplied so that vapour pressure of water equals 880 torr.

So, at 880 torr, boiling point of water will be more than 100 oC. In present case, most like the boiling point of water is equal to 105 oC.


Final answer:

Using the Clausius-Clapeyron equation, we can derive that the boiling point of water at 880 torr is closest to 90°C. Thus, among the given options, the boiling point of water at 880 torr is most likely to be 92°C.

Explanation:

The subject question is considering the boiling point of water at differing pressures. The standard boiling point of water is 100°C at 1 atmospheric pressure (or 760 torr). However, boiling point changes with changes in atmospheric pressure.

 By using the Clausius-Clapeyron equation, which establishes a relationship between the vapor pressure and temperature of a substance, we can establish that at 880 torr, the boiling point is likely to be close to 90°C, given that the vapor pressure of water is 68kPa at about this temperature. Therefore, among the options given, 92°C is the most likely boiling point of water at 880 torr.

Learn more about Boiling Point here:

https://brainly.com/question/2153588

#SPJ3

What is the standard emf of a galvanic cell made of a cd electrode in a 1.0 m cd(no3)2 solution and a cr electrode in a 1.0 m cr(no3)3 solution at 25°c?

Answers

Standard reduction potential of Cd2+ = -0.403 v
Standard reduction potential of Cr3+ = -0.74 v

Here, reduction potential of Cd2+ is higher as compared to Cr3+. Hence, it will preferentially undergo reduction. 

The electrochemical cell is represented as
Cr/Cr3+// Cd2+/Cd

Now, standard EMF of cell = E = ECd2+/Cd - ECr3+/Cr  
                                                  = - 0.403. - (-0.74)
                                                  = 0.337 v


Final answer:

The standard emf of a galvanic cell with a Cd and Cr electrode in solutions of their respective 1.0 M nitrates at 25°C is 0.34 V.

Explanation:

To determine the standard emf of a galvanic cell made of a Cd electrode in a 1.0 M Cd(NO₃)₂ solution and a Cr electrode in a 1.0 M Cr(NO₃)₃ solution at 25°C, we must first identify the half-reactions taking place at each electrode and their standard reduction potentials (E°).

The standard half-cell potentials (available in standard reduction potential tables) for Cd2+ and Cr3+ are as follows:

 

The cathode is where reduction takes place, so the Cr3+ half-reaction will be the reduction (gain of electrons), and the Cd2+ half-reaction will be the oxidation at the anode (loss of electrons).

Next, we calculate the standard cell potential (E°cell) using the formula:

E°cell = E°cathode - E°anode

Since the Cr3+ half-reaction has the more negative standard reduction potential, it will be reversed to represent oxidation when it functions as the anode reaction. This gives us:

E°cell = (-0.40 V) - (-0.74 V) = 0.34 V

The positive standard cell potential indicates that the galvanic cell reaction is spontaneous under standard state conditions.

Which of the following compounds is not ionic?

A. CaCI2
B. NaI
C. CO2
D. Na2O

(P.S. All the 2's are subscript!)

Answers

The correct option is C.
An ionic compound is one which is made up of ions, which are held together by electrostatic force called ionic bonding. The compounds are usually made up of electrically charged particles, they have high melting and boiling points and they are good conduct of electricity. Ionic compounds are typically made up of metals and non metals.
Thus, CO2 is not an ionic compound, it is a covalent compound.

A 642 mL sample of oxygen gas at 23.5°C and 795 mm Hg, is heated to 31.7°C and the volume of the gas expands to 957 mL. What is the new pressure in atm?

Answers

Let's assume that O₂ is an ideal gas.

We can use combined gas law,
 PV/T = k (constant)

Where, P is the pressure of the gas, V is volume of the gas and T is the temperature of the gas in Kelvin.

For two situations, we can use that as,
P₁V₁/T₁= P₂V₂/T₂

P₁ = 795 mm Hg
V₁ =  642 mL
T₁ = (273 + 23.5) K = 296.5 K
P₂ = ?
V₂ = 957 mL
T₂ = (273 + 31.7) K = 304.7 K

By applying the formula,

795 mm Hg x 642 mL / 296.5 K = P₂ x 957 mL / 304.7 K
                                              P₂ = 548.07 mm Hg
                                              P₂ = 548 mm Hg
760 mmHg = 1 atm
548 mm Hg = 1 atm x (548 mmHg / 760 mmHg) = 0.721 atm

Pressure of gas = 
548 mm Hg = 0.721 atm

How many compounds, of the ones listed below, have hydrogen bonding? ch3(ch2)2nh2 ch3(ch2)2nh(ch2)4ch3 (ch3ch2)2n(ch2)4ch3?

Answers

Answer:
            Following two compounds have Hydrogen Bond Interactions;

                     1)  CH₃(CH₂)₂NH₂  (Propan-1-amine)

                     2)  CH₃(CH₂)₂NH(CH₂)₄CH₃  (N-propylpentan-1-amine)

Explanation:
                   Hydrogen Bond Interactions are formed between those molecules which has hydrogen atoms covalently bonded to most electronegative atoms like Fluorine, Oxygen and Nitrogen. This direct attachment of Hydrogen to electronegative atom makes it partial positive resulting in hydrogen bonding with neighbor's partial negative most electronegative atom. So, in above selected compounds it can be seen that both compounds contain hydrogen atoms directly attached to Nitrogen atoms, Therefore, allowing them to form Hydrogen Bonding Interactions.

The correct answer is a. 2 compounds have hydrogen bonding among the listed below.

To determine how many of the given compounds have hydrogen bonding, we must identify if they have hydrogen atoms attached to highly electronegative atoms like nitrogen (N), oxygen (O), or fluorine (F).

The compounds listed are:

CH₃(CH₂)₂NH₂CH₃(CH₂)₃NH(CH₂)₂CH₃(CH₃CH₂)₂N(CH₂)₄CH₃

Analysis

CH₃(CH₂)₂NH₂: Contains an N-H bond, so it can form hydrogen bonds.CH₃(CH₂)₃NH(CH₂)₂CH₃: Contains an N-H bond, so it can form hydrogen bonds.(CH₃CH₂)₂N(CH₂)₄CH₃: Does not contain an N-H bond, so it cannot form hydrogen bonds.

Based on this analysis, 2 out of the 3 compounds can form hydrogen bonds. Therefore, the correct answer is a. 2.

Correct question is: How many compounds, of the ones listed below, have hydrogen bonding?
CH₃(CH₂)₂NH₂  , CH₃(CH₂)₃NH(CH₂)₂CH₃ , (CH₃CH₂)₂N(CH₂)₄CH₃ ?
a. 2
b. 1
c. 0
d. 3

2,2-dimethyl-4-propyloctane has how many secondary carbons? view available hint(s) 2,2-dimethyl-4-propyloctane has how many secondary carbons? five nine six seven

Answers

Answer:
            2,2-dimethyl-4-propyloctane has SIX secondary carbons.

Explanation:

Secondary Carbon:
                              In organic compounds secondary carbon is that carbon which is bonded to two carbon atoms and two hydrogen atoms. Below Red arrows indicate secondary carbons.

Primary Carbon:
                          Primary carbon is that carbon which is further attached to one carbon atom and three hydrogen atoms. Below in structure Blue arrows indicate primary carbons.

Tertiary Carbon:
                         These are those carbons which are bonded to to at least three carbon atoms. Below Green arrows indicate tertiary carbons.
Final answer:

The molecule 2,2-dimethyl-4-propyloctane has five secondary carbons which are those bonded to two other carbon atoms.

Explanation:

The hydrocarbon 2,2-dimethyl-4-propyloctane belongs to the class of alkanes, characterized by single bonds between carbon atoms. This molecule consists of an 8-carbon chain (octane), with three side branches: two methyl groups (-CH3) on the second carbon and a propyl group (-CH2-CH2-CH3) on the fourth carbon. When identifying secondary carbons, which are carbon atoms bonded to two other carbon atoms, it becomes evident that 2,2-dimethyl-4-propyloctane contains five secondary carbons.

The two carbons on either end of the main chain don't fit the criteria of secondary carbons as they are bonded to only one other carbon atom. The five secondary carbons are as follows: two from the main chain (excluding the ends); two found at the ends of the propyl branch; and one where the methyl branches connect to the main chain.

Learn more about Secondary Carbons here:

https://brainly.com/question/35559152

#SPJ11

Calculate the k sp for zinc hydroxide if the solubility of zn (oh)2 in pure water is 2.1 × 10-4 g/l. calculate the k sp for zinc hydroxide if the solubility of zn (oh)2 in pure water is 2.1 × 10-4 g/l. 2.9 × 10-3 1.5 × 10-3 9.9 × 10-18 3.8 × 10-17

Answers

Zinc hydroxide is a uni-bi type of electrolyte.
For such systems, k sp = 4S^3
where S = solubility in mol/l

Now for Zinc hydroxide, molecular weight = 99.4

so,  solubility = 2.1 x 10-4 g/l = 2.11 X 10^-6 mol/l
Finally, k sp = 4S^3 = 4 X (2.11 X 10^-6)^3 = 3.77 X 10^-17

The [tex]\( K_{sp} \)[/tex] for zinc hydroxide is [tex]\[ 3.8 \times 10^{-17}}\][/tex]

1. Molar mass of  [tex]\( \text{Zn(OH)}_2 \)[/tex]:

  [tex]\[ \text{Zn} = 65.38 \, \text{g/mol}, \, \text{O} = 16.00 \, \text{g/mol}, \, \text{H} = 1.01 \, \text{g/mol} \][/tex]

 [tex]\[ \text{Molar mass} = 65.38 + 2 \times (16.00 + 1.01) = 99.40 \, \text{g/mol} \][/tex]

2. Molar solubility [tex]\( s \)[/tex]:

  [tex]\[ \text{Solubility} = 2.1 \times 10^{-4} \, \text{g/L} \][/tex]

 [tex]\[ s = \frac{2.1 \times 10^{-4}}{99.40} \approx 2.11 \times 10^{-6} \, \text{mol/L} \][/tex]

3. Ksp expression:

 [tex]\[ \text{Zn(OH)}_2 \rightleftharpoons \text{Zn}^{2+} + 2\text{OH}^- \][/tex]

 [tex]\[ K_{sp} = [\text{Zn}^{2+}][\text{OH}^-]^2 = s \cdot (2s)^2 = 4s^3 \][/tex]

4. Calculate [tex]\( K_{sp} \):[/tex]

 [tex]\[ K_{sp} = 4 \times (2.11 \times 10^{-6})^3 = 4 \times 9.39 \times 10^{-18} \approx 3.76 \times 10^{-17} \][/tex]

To 100.0 g water at 25.00 ºc in a well-insulated container is added a block of aluminum initially at 100.0 ºc. the temperature of the water once the system reaches thermal equilibrium is 28.00 ºc. what is the mass of the aluminum block? (the specific heat capacity of al is 0.900 j g–1 k–1 .)

Answers

when the amount of heat gained = the amount of heat loss

so, M*C*ΔTloses = M*C* ΔT gained

when here the water is gained heat as the Ti = 25°C and Tf= 28°C so it gains more heat.

∴( M * C * ΔT )W = (M*C*ΔT) Al

when Mw is the mass of water = 100 g 

and C the specific heat capacity of water = 4.18

and ΔT the change in temperature for water= 28-25 = 3 ° C

and ΔT the change in temperature for Al = 100-28= 72°C

and M Al is the mass of Al block

C is the specific heat capacity of the block = 0.9 

so by substitution:

100 g * 4.18*3 = M Al * 0.9*72

∴ the mass of Al block is = 100 g *4.18 / 0.9*72

                                          = 19.35 g 





The jaeger reading cards are used to test _____ vision

Answers

The Jaeger reading cards are used to test near vision. It's usually held by a patient at a certain distance from the eye depending on the size being read. The smallest letters one can read is what determines their visual acuity!

The Jaeger reading cards are used to test near vision. The correct answer is "near" vision.

The Jaeger reading cards are used to test near vision, which is the ability to see objects clearly at a close distance, typically around 14 to 16 inches away from the eyes. This type of vision is important for activities such as reading, writing, and working on a computer. The Jaeger chart consists of blocks of text in various sizes, with the smallest print at the bottom and the largest at the top. A person being tested reads the text from top to bottom until they can no longer clearly distinguish the letters, which helps determine their near visual acuity.

suppose you like to listen to two different radio stations. The opera station broadcasts at 90.5 MHz and the rock and roll station broadcasts at 107.0 MH.s. which station's signal has waves with longer wavelenghts and which stations signal has station has waves with higher energy?

Answers

The "Opera" at 90.5 MHz has lower frequency, so its wavelength is longer.
Whichever station is transmitting with higher power has waves with higher energy.
Each photon of the transmission at 107.1 MHz carries more energy,because the energy of a photon is proportional to its frequency. But it's a mistake to think that the station at higher frequency haswaves with higher energy.

The rock and roll station at [tex]107.0 MHz[/tex] has higher energy photons with approximately [tex]\(7.09 \times 10^{-26}\) joules[/tex]

The opera station at [tex]90.5 MHz[/tex] has lower energy photons with approximately [tex]\(5.99 \times 10^{-26}\) joules.[/tex]

To determine which radio station's signal has longer wavelengths and which has higher energy, we need to use the relationships between frequency, wavelength, and energy for electromagnetic waves.

1. Wavelength

The wavelength (\(\lambda\)) of a wave is related to its frequency ([tex]\(f\)[/tex]) and the speed of light ([tex]\(c\)[/tex]) by the equation:

[tex]\[ \lambda = \frac{c}{f} \][/tex]

Where:

[tex]\(c\)[/tex] is the speed of light ([tex]\(3 \times 10^8\) meters per second[/tex]).

[tex]\(f\)[/tex] is the frequency of the wave.

Opera Station ([tex]90.5 MHz[/tex])

Frequency: [tex]\(90.5 \times 10^6\) Hz[/tex]

[tex]\[ \lambda_{\text{opera}} = \frac{3 \times 10^8 \, \text{m/s}}{90.5 \times 10^6 \, \text{Hz}} = \frac{3 \times 10^8}{90.5 \times 10^6} = 3.31 \, \text{meters} \][/tex]

Rock and Roll Station ([tex]107.0 MHz[/tex])

Frequency: [tex]\(107.0 \times 10^6\) Hz[/tex]

[tex]\[ \lambda_{\text{rock}} = \frac{3 \times 10^8 \, \text{m/s}}{107.0 \times 10^6 \, \text{Hz}} = \frac{3 \times 10^8}{107.0 \times 10^6} = 2.80 \, \text{meters} \][/tex]

The opera station at [tex]90.5 MHz[/tex] has a longer wavelength of approximately [tex]3.31 meters[/tex].

The rock and roll station at [tex]107.0 MHz[/tex] has a shorter wavelength of approximately [tex]2.80 meters[/tex]

2. Energy

The energy ([tex]\(E\)[/tex]) of a photon is related to its frequency ([tex]\(f\)[/tex]) by the equation:

[tex]\[ E = h f \][/tex]

Where:

[tex]\(h\)[/tex] is Planck's constant ([tex]\(6.626 \times 10^{-34}\) Joule seconds[/tex]).

[tex]\(f\)[/tex] is the frequency of the wave.

Opera Station ([tex]90.5 MHz[/tex])

[tex]\[ E_{\text{opera}} = 6.626 \times 10^{-34} \, \text{Js} \times 90.5 \times 10^6 \, \text{Hz} = 5.99 \times 10^{-26} \, \text{J} \][/tex]

Rock and Roll Station ([tex]107.0 MHz[/tex])

[tex]\[ E_{\text{rock}} = 6.626 \times 10^{-34} \, \text{Js} \times 107.0 \times 10^6 \, \text{Hz} = 7.09 \times 10^{-26} \, \text{J} \][/tex]

¿A shaker of salt substitute contains 1.6 oz of K. What is the activity, in milliCuries, of the potassium in the shaker? The activity is 7 microcuries (µCi)

Answers

We know K-40 (potassium having atomic mass 40 g) is radioactive and its natural abundance is 0.012% 
So for 1 mol of potassium contains 0.00012 mol of K-40 
Now 1.6 oz of K = 45.36 g of K
average atomic weight of K = 39.1 g
so 45.36 g of K contains:
(45.36 / 39.1) * 0.00012 * 6.022 x 10²³ (atoms of K-40)
= 8.4 x 10¹⁹ atoms of K-40
We know, activity A is:
A = 0.693 / t1/2 N₀
[t1/2 : half life time and N₀ : initial number of atoms]
t1/2 of K-40 = 1.28 x 10⁹ years
    = 4.04 x 10¹⁶ seconds
So A = (0.693 / 4.04 x 10¹⁶) * (8.4 x 10¹⁹ ) = 1441 cps
A = 141 x (1/3.7 x 10¹⁰)   because 3.7 x 10¹⁰ cps = 1 Ci
A = 3.9 x 10⁻⁸ Ci  = 3.9 x 10⁻⁵ millicurie

Sodium is produced by electrolysis of molten sodium chloride. what are the products at the anode and cathode, respectively?

Answers

When sodium chloride is molten:
NaCl ------> Na⁺ +Cl⁻
Anod (+)                                           |             Cathode (-)
2Cl⁻-2e⁻ ---> Cl2(gas)                     |          Na⁺ + e⁻ -----> Na⁰(s)

Which carbonyl compounds do not undergo an aldol reaction when treated with −oh in h2o? select all that apply?

Answers

Answers:
              Among many few compounds are shown below which can not undergo Aldol Condensation reactions.

Explanation:
                   Aldol Condensation reactions are given by those carbonyl compounds which are capable of forming conjugate bases called as Enolates. Enolates are formed when carbonyl compounds having hydrogen atoms at alpha position are treated with strong bases. This hydrogen atom at alpha position is mildly acidic in nature and readily donated to base as the upcoming conjugate base i.e. has stability due to resonance. 
                  So those carbonyl compounds which lacks these acidic protons at alpha position are not able to form enolates, Hence, unable to undergo Aldol Condensation reactions. Few examples are attached below,

Carbonyl compounds that do not undergo an aldol reaction include those without alpha-hydrogens like formaldehyde and benzaldehyde, as well as esters, acids, and amides.

These compounds either lack necessary alpha-hydrogens or have structures that are unfavorable for aldol reactions.

In an aldol reaction, carbonyl compounds like aldehydes and ketones with alpha-hydrogens can react in the presence of a base such as hydroxide (−OH) in water. However, not all carbonyl compounds undergo this reaction.

Carbonyl compounds that do not undergo an aldol reaction include those without alpha-hydrogens, such as formaldehyde and benzaldehyde. Additionally, carbonyl compounds like esters, acids, and amides typically do not participate in aldol reactions due to their structural properties.

Examples of Carbonyl Compounds Not Undergoing Aldol Reaction:

Formaldehyde (H-CHO)Benzaldehyde (C₆H₅CHO)Ester (R-COOR')Acid (R-COOH)Amide (R-CONH₂)

These compounds either lack the necessary alpha-hydrogens or have structures that are unfavorable for aldol reactions.

Which statement best describes how the scientific community analyzes data?

Answers

Answer:

Scientists can come to different conclusions based on the same data

Explanation:

Matter are anything that is made up of atoms. The quantity of matter can be observed only on the basis of mass and volume calculation. Thus,  scientists can come to different conclusions based on the same data is the statement that describes how the scientific community analyzes data.

What is matter?

Matter is a substance that has some mass and can occupy some volume. The matter is mainly used in science. Matter can be solid, liquid or gas.

So as we saw that matter has some mass so mass can be measured in gram only. Mass can also be represented as number of molecules. We also saw that matter occupy some volume and that volume is measured only in liter. Scientists can come to different conclusions based on the same data is the statement that describes how the scientific community analyzes data.

Thus,  scientists can come to different conclusions based on the same data is the statement that describes how the scientific community analyzes data.

To learn more about matter, here:

https://brainly.com/question/4562319

#SPJ5

The normal boiling point of water is 100.0 °c and its molar enthalpy of vaporization is 40.67 kj/mol. what is the change in entropy in the system in j/k when 51.1 grams of steam at 1 atm condenses to a liquid at the normal boiling point?

Answers

we are going to use this formula:

Δ H = T * ΔS

when Δ H is the change in enthalpy 

and T is the temperature in Kelvin = 100+273= 373 K

and ΔS is the change in entropy

but first, we need to get the value of ΔH:

ΔH = mass * molar mass per mole * enthalpy of vaporization

by substitution:

ΔH = 51.1 g * (1 mole/18g) * 40.67KJ/mole

      = -115.5 KJ

we use negative sign because this is an exothermic reaction.

by substitution on the first formula, we will get the change of entropyΔS:

ΔS = ΔH / T

     = -115.5 KJ / 373K

     = 310 J/K
Final answer:

The change in entropy in the system is 308.3 J/K.

Explanation:

The change in entropy in the system can be calculated using the formula ∆S = ∆Hvap/T. Here, ∆Hvap is the molar enthalpy of vaporization of water, which is given as 40.67 kJ/mol. T is the temperature in Kelvin, which can be calculated by adding 273.15 to the boiling point of water in Celsius. So, T = 100.0 + 273.15 = 373.15 K. Plugging in these values in the formula, we get:

∆S = (40.67 kJ/mol)/(373.15 K) = 0.1089 kJ/(mol·K)

Now, we need to convert grams of steam to moles of steam. The molar mass of water is 18.015 g/mol. So, 51.1 g of steam is equal to (51.1 g)/(18.015 g/mol) = 2.835 mol. Multipling this with the change in entropy, we get:

∆S = (0.1089 kJ/(mol·K)) · (2.835 mol) = 0.3083 kJ/K

Finally, to convert kJ/K to J/K, we multiply by 1000:

∆S = (0.3083 kJ/K) · (1000 J/1 kJ) = 308.3 J/K

Learn more about entropy here:

https://brainly.com/question/38613023

#SPJ11

What is the daughter nucleus (nuclide) produced when 90sr undergoes beta decay by emitting an electron? replace each question mark with the appropriate integer or symbol?

Answers

beta decay by emitting an electron is called as β⁻ decay. when this happens, a neutron of the element converts into a proton by emitting an electron. Hence, the mass of daughter nucleus is same as parent atom but atomic number/number of protons is higher by 1 than atomic number of parent atom.

Sr has atomic number as 38.

After β⁻ decay, the daughter nucleus will have atomic number as 38 + 1 = 39.
Hence, the daughter nucleus should be Y (Yttrium). Formula is,

₃₈⁹⁰Sr → ₃₉⁹⁰Y + ₋₁⁰β + energy

Final answer:

The daughter nuclide produced when ¹°Sr undergoes beta decay is ¹°Y (yttrium-90), which is represented by the nuclear equation ¹°Sr → ¹°Y + β⁻.

Explanation:

When ¹°Sr undergoes beta decay, it emits an electron (beta particle) and transforms into a different element. The loss of the electron results in an increase of the atomic number by one while the mass number remains the same. Therefore, the new atomic number will be 39 (as strontium has atomic number 38), and the mass number stays at 90. The daughter nuclide produced from this decay is ¹°Y (yttrium-90).

The nuclear equation for this ß-decay process is:
¹°Sr → ¹°Y + β⁻

If 32.5 grams of CaO are dissolved in 212 grams of water, what is the concentration of the solution in percent by mass?

6.52% CaO

8.67% CaO

13.3% CaO

15.3% CaO

Answers

percent by mass of CaO= Mass of solute/ moles of solution x 100%

(32.5g)/ (32.5g+212g) x 100%
= 13.29 and when you round it becomes 13.3% CaO

Answer:

Concentration of solution in percent by mass is 13.3% CaO

Explanation:

% by mass = [tex]\frac{mass of solute}{mass of solution}\times 100[/tex]

Here solute is CaO and solvent is water.

So, mass of solution = (mass of solute)+(mass of solvent)

                                  = (mass of CaO)+(mass of water)

                                   = 32.5 g + 212 g

                                    = 244.5 g

So, Concentration of solution by percent mass = [tex]\frac{mass of CaO}{mass of solution}\times 100[/tex] = [tex]\frac{32.5}{244.5}\times 100[/tex] = 13.3 %

A 135 g sample of carbon disulfide requires 43.2 kj of heat to vaporize completely. what is the enthalpy of vaporization for carbon disulfide?
a. 1.77 kj/mol
b. 24.4 kj/mol
c. 76.2 kj/mol
d. 0.320 kj/mol
e. 3.13 kj/mol

Answers

Molecular weight of CS2 = 76.14 g

number of moles of CS2 = [tex] \frac{weight.of.CS2}{molecular.weight} [/tex]
                                        = [tex] \frac{135}{76.14} [/tex]
                                        = 1.773

Now, 1.733 mol requires 43.2 kj of heat to vaporize.
∴  1 mol will require [tex] \frac{43.2}{1.77} [/tex] = 24.4 kj/mol

Thus, correct answer is option B

A solution of 0.90 g of an unknown nonelectrolyte in 100 ml of water at 27◦c has an osmotic pressure of 0.55 atm. what is the molecular weight of this compound? (assume

Answers

Osmotic pressure is mathematically expressed as
π = CRT
where,  C = concentration of solution
R = gas constant = 0.082 atm mol-1 K-1
T = temperature = 300 K
π = osmotic pressure = 0.55 atm

∴ 0.55 = C X 8.314 X 300
∴C = 0.022 M

Now, conc of solution (in terms of molarity) = [tex] \frac{\text{weight of solute}}{\text{molecular weight X volume of solution(l)}} [/tex]

Given: weight of solute = 0.9 g
volume of solution = 100 ml = 0.1 l

∴ 0.022 = [tex] \frac{0.9}{\text{molecular weight X 0.1}} [/tex]
∴ Molecular weight = 4.09 g/mol

A 36.41-g sample of calcium carbonate (CaC O 3 )
contains 14.58 g of calcium and 4.36 g of carbon.

What is the mass of oxygen contained in the sam-
ple? What is the percent by mass of each element in

this compound?

Answers

m(O) = m(CaCO₃) - m(Ca) - m(C).
m(O) = 36.41 g - 14.58 g - 4.36 g.
m(O) = 17.47 g.
ω(Ca) = m(Ca) ÷ m(CaCO₃) · 100%.
ω(Ca) = 14.58 g ÷ 36.41 g · 100%.
ω(Ca) = 40 %; mass percent of calcium.
ω(C) = m(C) ÷ m(CaCO₃) · 100%.
ω(C) = 4.36 g ÷ 36.41 g · 100%
ω(C) = 12%; mass percent of carbon.
ω(O) = 100% - ω(Ca) - ω(C).
ω(O) = 100% - 40% - 12%.
ω(O) = 48%; mass percent of oxygen.

To lift a load of 100 N a distance of 1 m an effort of 25 N must be applied over an inclined plane of length 4 m. What must be done to lift the load 2 m, using the same effort? A.Use an inclined plane of length 8 m.

B.Use an inclined plane of length 2 m.

C.Use an inclined plane of length 10 m

D.Use an inclined plane of length 16 m.

Answers

The answer is A, use an inclined plane of length 8.

Answer: The correct answer is A) Use an inclined plane of 8 m

Work :

Work is defined as force applied to an object to move it to some distance . It is calculated as product of force and displacement .

W = F* d

Where : W =work (N-m) F = force (N) d = displacement (m)

When a body is lifted , work can be expressed as :

W = m*g*h ( h = height )

Also force due to gravitation can be given as

F = m* g

where :

g = gravitational acceleration ([tex] 9.8 \frac{m}{s^2} [/tex]

Hence Work can be written as : W = F * h

Given :

Force on load due to gravitation = 100 N Height = 2 m

Force applied = 25 N displacement = ?

Work done to lift the load to 2 m = F * h

= 100 N * 2 m = 200 N-m

Plugging W = 200 N-m in work formula

W = F* d

200 N-m = 25 N * d

Dividing both side by 25 N

[tex] \frac{200N-m}{25 N} = \frac{25 N * d}{25 N} [/tex]

d = 8 m

Hence, to lift the load using 25 N , the inclined plane of 8 m can be used .

A sample of seawater contains 1.3g of calcium ions in 3,100kg of solution. what is the calcium ion concentration of this solution in units of ppm?

Answers

unit ppm stands for parts per million. in terms of mass, ppm is equivalent to mg/kg.
since 1 kg is 10⁻⁶ mg, 1 kg is equivalent to million mg.
therefore mg/kg is also ppm.
there are 1.3 g of Ca ions in 3100 kg
if 3100 kg contains - 1.3 g of Ca
then 1 kg contains - 1.3 g / 3100 kg
then Ca ions - 0.42 x 10⁻³ g/kg
Ca ion concentration - 0.42 mg/kg 
therefore Ca ion concentration is 0.42 ppm

hi i'm having trouble solving this question

" if 7.54 grams of Al reacts with excess of H2SO4, and makes 0.33g of H2 . What is the % yield of H2gas produced? 


Answers

Answer is:  the % yield of hydrogen gas produced is 58.9%.
m(Al) = 7.54 g.
n(Al) = m(Al) ÷ M(Al).
n(Al) = 7.54 g ÷ 27 g7mol.
n(Al) = 0.28 mol; amount of substance.
From chemical reaction: n(Al) : n(H₂) = 1 : 1.
n(H₂) = 0.28 mol.
m(H₂) = 0.28 mol · 2 g/mol.
m(H₂) = 0.56 g.
%yield = 0.33 g ÷ 0.56 g · 100%.
%yield = 58.9%.

Recrystallizing an anhydride (such as the product of this reaction) from water or an alcohol is rarely a good idea. explain why. be specific.

Answers

Final answer:

Recrystallization of an anhydride in water or alcohol is not effective because anhydrides will react with these solvents to form carboxylic acids or esters, respectively, thereby altering the compound instead of purifying it.

Explanation:

Recrystallizing an anhydride from water or an alcohol is often not ideal due to the reactive nature of anhydrides. Anhydrides undergo hydrolysis in the presence of water to form carboxylic acids, a process which is energetically favorable and further driven by the stabilization through hydrogen-bonding interactions among water molecules and the carboxylic acids. Moreover, anhydrides react with alcohols to yield esters. This means that instead of recrystallizing the anhydride, you are likely to convert it to other products, which defeats the purpose of recrystallization since you want to purify the anhydride, not change its chemical structure.

Which particle changes the mass of the isotope the most? which particle changes the mass of the isotope the most? electron capture positron emission gamma capture alpha particle neutron particle?

Answers

this question is absurd

Answer: Option (d) is the correct answer.

Explanation:

Species which contain same number of protons but different number of neutrons are known as isotope.  

For example, [tex]^{1}_{1}H[/tex] and [tex]^{3}_{1}H[/tex] are isotopes.

More is the mass of particle colliding with the isotope more will be the change in mass of an isotope due to emission of a heavier particle.

As alpha ([tex]^{4}_{2}He[/tex]) particle is heavier then a neutron, positron and gamma particles.

For example, [tex]^{14}_{7}N + ^{4}_{2}He \rightarrow ^{17}_{8}O[/tex]

Therefore, we can conclude that alpha particle changes the mass of the isotope the most.

The normal boiling point of ethanol (c2h5oh) is 78.3 °c and its molar enthalpy of vaporization is 38.56 kj/mol. what is the change in entropy in the system in j/k when 42.2 grams of ethanol at 1 atm condenses to a liquid at the normal boiling point?

Answers

when the entropy change of vaporization
       
 = enthalpy of vaporization/boiling point temperature 

when we have the enthalpy of vaporization = 38560 J/mol

and the boiling point temperature in Kelvin = 78.3 + 273 = 351.3 K

by substitution:

∴the entropy change of vaporization = 38560J/mol/351.3K

                                                               = 109.76 J/K/mol

and when the liquid has lesser entropy than the gas and we here convert from

gas to liquid so, the change in entropy = -109.76 J/K/mol

now, we need the moles of C2H5OH = mass/molar mass when the molar

mass of C2H5OH = 46 g/mol and mass = 42.2 g 

∴ moles of C2H5OH = 42.2 g / 46 g/mol = 0.92 moles

when 1 mol of C2H5OH turns in liquid entropy change →-109.76 J/K/mol

∴ 0.92 mol of C2H5OH → X

∴ X entropy change when 0.92 mol = -109.76 *0.92 mol / 1 mol

                                                             = 84.64 J/K


The change in the randomness of the system is the entropy change. The entropy change after condensation at the standard boiling point is 84.64 J/K.

What is the entropy change?

When a system undergoes the addition or deletion of the reactant and the products, then the disorder of the system is known as entropy change.

Given,

Enthalpy of vaporization = 38560 J/mol

Boiling point temperature = 351.3 K

[tex]\begin{aligned}\text{Entropy change of vaporization} &= \dfrac{\text{enthalpy of vaporization}}{\text{boiling point temperature}}\\\\&= \dfrac{38560}{351.3}\\\\&=109.76 \;\rm J/K/mol\end{aligned}[/tex]

Here, liquid has less entropy than gas hence the change in entropy is  -109.76 J/K/mol.

Moles of ethanol is calculated as:

[tex]\begin{aligned}\rm moles &= \dfrac{\rm mass}{\rm molar\; mass}\\\\&= \dfrac{42.2}{46}\\\\&= 0.92 \;\rm moles\end{aligned}[/tex]

If 1 mole of ethanol has an entropy change of -109.76 J/K/mol. Then, 0.92 moles will have,

[tex]\dfrac{-109.76 \times 0.92}{1} = 84.64\;\rm J/K[/tex]

Therefore, 84.64 J/K is the entropy change.

Learn more about entropy change here:

https://brainly.com/question/9864321

Complete the reactions to show how butanoic acid may be converted to butanal.

Answers

Butanoic Acid is converted to Butanal in two steps;

Step 1: Conversion of Butanoic Acid into Butyryl Chloride:

Butanoic Acid when treated with Thionyl Chloride gives Butyryl Chloride, SO₂ and HCl gases. This step is selected due to conversion of a bad leaving group (-OH) into a good leaving group (-Cl).

Step 2: Conversion of Butyryl Chloride to Butanal:

In this reaction the Butyryl Chloride is reduced to Butanal by treating Butyryl Chloride with a mild reducing agent i.e. Lithium tri tert-butoxy aluminum hydride.

Final answer:

Butanoic acid can be converted to butanal via a reduction process using a reducing agent such as lithium aluminum hydride, followed by hydrolysis.

Explanation:

Converting butanoic acid to butanal involves a reduction process, which can be carried out using reducing agents such as lithium aluminum hydride (LiAlH₄) or borane (BH₃). The reaction with LiAlH₄ is usually carried out in dry ether as a solvent, and it can be followed by careful hydrolysis to give the aldehyde, butanal. The overall reaction can be summarized as:

Butanoic acid (C₄H₈O₂) is treated with the reducing agent LiAlH₄.

The acid is reduced to the corresponding aldehyde, butanal (C₄H₈O).

After the reduction, the reaction mixture is hydrolyzed, which involves adding water to the reaction mixture.

This is different from esterification, which is the reaction between an acid and an alcohol, as described in the esterification of ethanol and butanoic acid to form ethyl butanoate and water.

The biochemical production of butanol from butyric acid is similarly not a direct route for synthesizing butanal, but it is an important process for biomass conversion.

What is the internal energy u of one mole of air on a very hot summer day (35∘c)? express your answer numerically in joules to two significant figures?

Answers

- For solving this problem, we have to take in account the degree of freedom of air molecules.
- As, molecules of air have five degrees of freedom (three translational and two rotational)
- For each molecule, the kinetic energy of each degree of freedom = 1/2 KT
- So, K.E of 1 molecule for 5 degrees of freedom = 5/2KT
So, for molecules of air K.E = 5/2 KT = 5/2 x 1 x 1.38 x 10⁻²³ x 308 = 1062.6 x 10⁻²³ J
1 mole of air contains 6.022 x 10²³ molecules 

K.E. of 1 mole = 1062.6 x 10⁻²³ x 6.022 x 10²³ = 6400 J

Final answer:

The internal energy (u) of one mole of air at 35°C is approximately 6400 J when calculated using the ideal gas law and assuming air is a diatomic gas.

Explanation:

The internal energy (u) of one mole of air on a very hot summer day, which is 35°C, can be estimated using the ideal gas law and the concept of heat capacity at constant volume (Cv). To find the internal energy, we must convert the given temperature to Kelvin by adding 273.15 to the Celsius temperature, which gives us 308.15 K (35°C + 273.15). Air is typically considered to be a diatomic molecule, particularly for dry air, which mainly consists of nitrogen and oxygen molecules. The approximate molar heat capacity at constant volume (Cv) for a diatomic gas like air is about 5R/2, where R is the universal gas constant (8.314 J/(mol·K)). Therefore, the internal energy (U) of one mole of air at this temperature is U = Cv × T = (5/2) × R × T. Plugging in the numbers, we get U = (5/2) × (8.314 J/(mol·K)) × (308.15 K). This would yield an internal energy of approximately 6412.5 J, which can be rounded to 6400 J to two significant figures.

Other Questions
Thomas bought a new backpack that was 30% off the original price. The sale resulted in a $15 discount. What was the original price of the backpack?a.) $45b.)$50c.)$65d.)$70 Your 2-year-old patient shows facial features, such as epicanthal folds, up-slanted palpebral fissures, single transverse palmar crease, and a low nasal bridge. These are referred to as After the data was recorded, Mary gives her latest book a rating of 1 star. How will this new rating affect the mean rating of her books? The mean book rating will not change. A bank currently has $100,000 in checkable deposits and $15,000 in actual reserves. if the reserve ratio is 20 percent, the bank has ________ in money-creating potential. if the reserve ratio is 14 percent, the bank has __________ in money-creating potential. -$5,000; $1,000. $20,000; $14,000. $5,000; $1,000. $3,000; $2,100. Use the guess-and-check method to solve the equation: 6(x + 3) + 1 = 31 China underwent many reforms in the 1970s, which reform(s) do you feel were the most influential in making China an economic powerhouse What is the most effective way to improve the efficiency of swimming strokes? An axiom in Euclidean geometry states that in space, there are at least points that do Read this excerpt from act III, scene I, of Shakespeares Romeo and Juliet: ROMEO: This gentleman, the prince's near ally, My very friend, hath got his mortal hurt In my behalf; my reputation stain'd With Tybalt's slander,Tybalt, that an hour Hath been my kinsman! O sweet Juliet, Thy beauty hath made me effeminate And in my temper soften'd valour's steel! What are two central ideas of the excerpt?Romeo blames falling in love with Juliet as the cause of Mercutios death.Romeo blames Tybalts hatred towards the Montagues as the cause of Mercutios death.Romeo blames his own cowardice and refusal to fight as the cause of Mercutios death.Romeo blames Mercutios impulsiveness as the cause of Mercutios death.Romeo blames Benvolios inability to stop the fight as the cause of Mercutios death Complete the steps in order to write the inverse of f(x) = x + 5 1. = x + 5 2. = y + 5 3. = y 4. = x 5 where was the war of 1812 fought The air in a cool region underneath cloud cover will have _____ a region with no cloud cover. A: In a cell, small vacuoles that are involved in transporting substances are often called Which of the following is the best linear approximation for f(x) = cos(x) near x= /2 The weather descriptions from the excerpts of "Marriage is a Private affair", such as the rain at the end, most accurately reveal an example of: Tone Theme Symbolism Point of View Loosening a kidney by removing adhesions is called what a sample of methane gas having a volume of 2.8 L at 25C and 1.65 atm was mixed with a sample of oxygen gas having a volume of 35L at 31C and 1.25 atm. The mixture was ignited to form carbon dioxide and water. Calculate the volume of carbon dioxide formed at a pressure of 2.5 atm and a temperature of 125C which term describes the cultural movement in New York City that resulted from the black migration of the 1920s A the lost generationB The Harlem Renaissance C The Gilded ageD the Jazz age For several months, a restaurant manager collected data on the number of people at a table (p) and the total bill, in dollars (d). She found that there is a positive linear association between p and d that is best modeled by the equation d = 15.7p + 2.0.What statement is true?The model predicts that the average total bill for a table is $15.70.The model predicts that for each additional 2 people at a table, the total bill increases by $15.70.The model predicts that the average bill for any table with 2 people is $15.70.The model predicts that for each additional person at a table, the total bill increases by $15.70. Lets change it what does this quote reveal about Jonas