What is the volume of 0.250 m hydrochloric acid required to react completely with 20.0 ml of 0.250 m ca(oh)2?

Answers

Answer 1
the balanced equation for the above neutralisation reaction is as follows;
Ca(OH)₂ + 2HCl ----> CaCl₂ + 2H₂O
Stoichiometry of Ca(OH)₂ to HCl is 1:2
number of Ca(OH)₂ moles reacted - 0.250 mol/L x 20.0 x 10⁻³ L = 5.00 x 10⁻³ mol
according to molar ratio of 1:2
number of HCl moles required = 2 x number of Ca(OH)₂ moles reacted
number of HCl moles = 5.00 x 10⁻³ x 2 = 10.0 x 10⁻³ mol
molarity of HCl solution - 0.250 M
there are 0.250 mol  in volume of 1 L
therefore 10.0 x 10⁻³ mol in - 10.0 x 10⁻³ mol  / 0.250 mol/L = 40.0 mL 
40.0 mL of 0.250 M HCl is required

Related Questions

How many moles are equivalent to 2.50x1020 atoms of Fe?

Answers

Final answer:

To find the  moles equivalent to 2.50x10²⁰ atoms of Fe, you divide the given number of atoms by Avogadro's number (6.022x10²³ atoms/mole). This yields approximately 0.415 moles of Fe.

Explanation:

To calculate the number of moles equivalent to 2.50x10²⁰ atoms of Fe (Iron), you can use Avogadro's number, which is 6.022x10²³ atoms/mole. Let's divide the given no. with Avogadro's number. Let's do the computation:

2.50x10²⁰ atoms Fe * (1 mol Fe / 6.022x10²³ atoms Fe) = ~0.415 moles of Fe

This means that 2.50x10²⁰ atoms of Fe is equivalent to 0.415 moles. Avogadro's number is a fundamental constant in chemistry and is used to convert between the atomic scale and macroscopic scale.

Learn more about Avogadro's number here:

https://brainly.com/question/33720401

#SPJ12

Final answer:

2.50x10^20 atoms of Fe are equivalent to approximately 4.15x10^-4 moles. This is calculated by dividing the number of atoms by Avogadro's number (6.022x10^23 atoms per mole).

Explanation:

To calculate how many moles are equivalent to 2.50x10^20 atoms of Fe, we use Avogadro's number, which states that one mole of any substance contains 6.022x10^23 elementary entities (like atoms). Therefore, to convert the number of atoms to moles, we divide the number of atoms by Avogadro's number.

In this case, (2.50x10^20) / (6.022x10^23), which equals approximately 4.15x10^-4 moles of Fe.

Learn more about Moles and Atoms here:

https://brainly.com/question/8512069

#SPJ12

A student adds too much hcl during the titration. will the calculated ksp be too high, too low, or unaffected? why?

Answers

A student adds too much HCl during the titration, the calculated ksp be too high.

Reason
Ksp refers to solubility product. It is a measure of solute present in solution. Now, when a sparingly solution base, like calcium hydroxide, is titrated with an acid, like HCl. The reaction results in generation of salt (in present case CaCl2) and water. The solubility of salt is higher as compared to sparingly soluble base. So during the  course of reaction, Ca^2+ ions present in system will combine with Cl^- ions to form CaCl2. This will result in decreasing in conc. of Ca^2+ ions in solution. To compensate for this lose, more Ca^2+ ions from Ca(OH)2 will dissolve in solution. Thus, Ksp value will increase. 

For the oxidation–reduction reaction equation 2na+s ⟶ na2s indicate how many electrons are transferred in the formation of one formula unit of product.

Answers

2Na⁰ +S⁰ ---> [tex]Na_{2}^{+1}S^{-2}[/tex]

[tex]2Na^{0} -2e^{-} ---\ \textgreater \ 2Na^{+1} S^{0} +2e^{-}----\ \textgreater \ S^{-2} 2 electrons are transferred from Na to S.[/tex]

The given reaction of metallic sodium with sulphur involves two electrons which are lost  from two sodium atoms and gained by the sulphur atom. Thus sodium atom oxidizes from 0 to +1 and sulphur reduces from 0 to -1.

What is redox reaction?

A redox reaction involves oxidation of one reactant species and reduction of other species. The species which loss or donate electrons are oxidized to higher oxidation states whereas, the species which gain one or more electrons are reduced to lower oxidation states.

Metals are electron rich and will lose electrons easily to a non-metal during chemical bonding. Here the valency of sulphur is two thus it needs to gain 2 electrons. One sodium donate one electrons and thus two sodium atoms are needed to react with sulphur.

The oxidation reaction here is :

[tex]\rm 2 Na \rightarrow 2Na^{+} + 2 e^{-}[/tex]

Reduction of sulphur is written as:

[tex]\rm S + 2e ^{-} \rightarrow S^{2-}[/tex]

Therefore, the number of electrons involved in this oxidation -reduction reaction is 2.

To find more on redox reactions, refer here:

https://brainly.com/question/13978139

#SPJ2

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 





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 student completes a titration by adding 12.0 milimeters of NaOH(aq) of unknown concentration to 16.0 milimeters of 0.15 HCl(aq). What is the molar concentration of the NaOH(aq)?

Answers

the balanced equation for the above reaction is as follows
NaOH  + HCl ---> NaCl + H₂O
stoichiometry of NaOH to HCl is 1:1
number of HCl moles reacted - 0.15 mol/L x 0.0160 L = 0.0024 mol
therefore number of NaOH moles reacted - 0.0024 mol
there are 0.0024 mol of NaOH in 12.0 mL
therefore in 1000 L - 0.0024 mol / 12.0 mL x 1000 mL = 0.20 mol
molarity of NaOH is 0.20 M

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

What is the total number of molecules in a 0.5-mole sample of the He gas?

Answers

Avogadro’s constant tells us the number of atoms in a mole of any substance: 6.022x10^23. A mole of water, oxygen, sodium - they all have this many atoms in a 1 mole sample.

A 0.5 mole sample of helium gas would contain 0.5 x (6.022 x 10^23) atoms, or 3.011 x 10^23 atoms. Still a big amount.

Answer :  The total number of molecules in 0.5 mole of sample of He gas are, [tex]3.011\times 10^{23}[/tex]

Explanation : Given,

Moles of sample of He gas = 0.5 mole

As we know that,

1 mole of gas contains [tex]6.022\times 10^{23}[/tex] number of molecules of gas

As, 1 mole of He gas contains [tex]6.022\times 10^{23}[/tex] number of molecules of He gas

So, 0.5 mole of He gas contains [tex]0.5\times (6.022\times 10^{23})=3.011\times 10^{23}[/tex] number of molecules of He gas

Therefore, the total number of molecules in 0.5 mole of sample of He gas are, [tex]3.011\times 10^{23}[/tex]

Calculate the change in entropy that occurs in the system when 48.6 g of water (h2o) vaporizes from a liquid to a gas at its boiling point (100.0 ∘c). the heat of vaporization is 40.7 kj/mol.

Answers

The water is vaporizing at 100°C. The vaporizing water is the system to be studied. Given the mass of water is 48.6 g. The chemical formula of water is H₂O. The molar mass of water is 18 g/ mol
moles of water are:
moles = mass / molar mass = 48.6 / 18 = 2.7 mol
The water is vaporizing, Thus, it gains the heat energy to vaporize
The amount of heat gained by the water is:
Q = n ΔH⁰ vap
   = 2.7 mol x 40.7 kJ/mol x 1000J / 1kJ = 109890 J
Q is the amount of heat lost or gained, n is the number of moles of water and ΔH⁰vap is heat of vaporization.
The expression for entropy change is:
ΔS = Q / T = 109890 J / 373 K = 294.6 J/K
The change in the entropy of the system to three significant digits is 295 J/K

When 48.6 g of water vaporizes at its boiling point (100.0 °C), the change in the entropy is 0.292 kJ/K.

First, we will calculate the change in the enthalpy (ΔH) when 48.6 g of water vaporizes considering the following relationships.

The heat of vaporization of water is 40.7 kJ/mol.The molar mass of water is 18.02 g/mol.

[tex]\Delta H = 48.06 g \times \frac{1mol}{18.02g} \times \frac{40.7kJ}{mol} = 109kJ[/tex]

Then, we will convert 100.0 °C (T) to Kelvin using the following expression.

[tex]T = K = \° C + 273.15 = 100.0\° C + 273.15 = 373.2 K[/tex]

Finally, we will calculate the change in the entropy (ΔS) for this process using the following expression.

[tex]\Delta S = \frac{\Delta H }{T} = \frac{109kJ}{373.2K} = 0.292kJ/K[/tex]

When 48.6 g of water vaporizes at its boiling point (100.0 °C), the change in the entropy is 0.292 kJ/K.

Learn more: https://brainly.com/question/13146879

Write the equilibrium-constant kp expression for the reaction a(g) + 2b(l) = 4c(g) + d(g)

Answers

Final answer:

For the reaction a(g) + 2b(l) = 4c(g) + d(g), the equilibrium constant expression using partial pressures, Kp, is Kp = (Pc)^4 (Pd) / (Pa).

Explanation:

To write the equilibrium-constant expression, Kp, for the reaction a(g) + 2b(l) = 4c(g) + d(g), we apply the principles of equilibrium for gases. Kp is an equilibrium constant calculated from partial pressures of gas-phase reactants and products at equilibrium. The liquids are not included in the Kp expression since their activities are considered constants under standard conditions and do not affect the equilibrium of gases.

The general form of an equilibrium constant expression for a reaction is Kp = (Pc)c (Pd)d / (Pa)a (Pb)b, where P represents the partial pressure of each gas, the lower-case letters right below the P are the chemical species, and the upper-case letters indicate the stoichiometric coefficients from the balanced equation.

Using the reaction given, we write the Kp expression as follows:

Kp = (Pc)4 (Pd) / (Pa)

Note that in our Kp expression, we do not include B since it is in the liquid state.

What is the percent by mass of chlorine in NaCl?

Answers

Answer: 60.7 percent


Hope this helped
Here’s the specific numbers to get you along

The normal boiling point of 2-propanol, (ch3)2choh, is 83 ºc, while that of acetone, (ch3)2c=o, is 56 ºc. what is the principal reason for the greater boiling point of 2- propanol?

Answers

2-Propanol has higher boiling point than acetone due to the inter-molecular hydrogen bond formation of 2-propanol which increase the intermolecular forces between molecules and leads to higher boiling point in propanol while in case of acetone the intermolecular present between molecules are dipole-dipole interaction which has smaller effect when compared to hydrogen bond  

If two nonmetals with the same electronegativity bond, what type of bond will form?
A. Metallic bond
B. Non polar ionic bond
C. Ionic bond
D. Non polar covalent bond

Answers

If two nonmetals with the same electronegativity bond, what type of bond will form then Non polar covalent bond (option D) will form.

Answer:

Two nonmetals with the same electronegativity will form a non polar covalent bond.

Explanation:

The type of bond between atoms is classified in 3 big groups:

Metallic bond: this type of bond only take place between metallic atoms like Cu, Al, Au, etc.Ionic bond: this type of bond is formed between ions, that means that it is necessary the presence of a cation (ion with positive charge) and and an anion (ion with negative charge) and when the atoms has a very high difference of electronegativity (more that 2), that makes the ionic bond always polar, because there will be always a positive pole (cation) and a negative pole (anion). This is common between a metal and a nonmetal, for example: sodium chloride (NaCl).Covalent bond: this type of bond occurs when atoms share one or more pairs of electrons, this happens between nonmetals, e.g.: the molecule of chlorine gas (Cl₂).

Apart from that, depending on the electronegativity difference, the covalent bonds are clasified in polar and non polar:

- Polar covalent bond: the difference of electronegativity is important but less than an ionic bond (between 0 and 2).

- Non polar covalent bond: this occurs when the atoms forming bonds have the same electronegativity.

So, analyzing the statement, if we have two nonmetals it is a covalent bond, and if the two nonmetals atoms have the same electronegativity the bond will be non polar.

PLEASE ANSWER FAST!!!

2/ Immediately after the Big Bang, the universe began to?
A/ cool down
B/ heat up
C/shrink
D/ condense

3/ A ____ Is a system of billions of stars and all of the planets that orbit around them?
A/ solar system
B/ universe
C/ galaxy
D/ planet

5/ Light energy moves in?
A/ waves
B/particles
C/ condensation
D/ plasma

6/ All of matter and energy in the universe was once contained in?
A/ a star
B/ a galaxy
C/ an element
D/ a singularity

Answers

2- Condense
3- ?
5- Waves
6- Star
I hope this helps! :)
For the question 1. It is A started to cool down

Consider the ground state of the silicon atom (z = 14). what is the electronic configuration for this state?

Answers

Hello, 

Considering this ground state, the electron configuration for it would be (1s)2 (2s)2 (2p)6 (3s)2 (3p)2 of silicon atom (z = 14). 

Let me know if you need further info. :)

                  - Dotz 

Determine the hydronium ion concentration in a solution that is 0.0005 m hcl. answer in units of m.

Answers

H₃O ions are when water is protonated
H₂O + H⁺ --> H₃O⁺
HCl is a strong acid therefore complete ionisation takes place.
HCl ---> H⁺ + Cl⁻
1 mol of HCl dissociates to give out 1 mol of H⁺
since H⁺ together with water forms H₃O⁺ ions,
[HCl] = [H₃O⁺]
therefore concentration of [H₃O⁺] is 0.0005 M

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.

Tin (II) fluoride , SnF2, is found in some toothpastes. Tin (III) fluoride is made by reacting solid tin with hydrogen fluoride according to the following BALANCED equation. Sn(s) + 2 HF (g) -> SnF2(s) + H2(g) How many moles of tin are needed to react with 8.4 moles of hydrogen fluoride ?

Answers

The Balance Chemical Equation is as;

                                 Sn  +  2 HF   →    SnF₂  +  H₂

According to Equation,

                        2 Moles of HF requires  =  1 Mole of Sn
So,
                 8.4 Moles of HF will require  =  X Moles of Sn

Solving for X,
                            X  =  (8.4 mol × 1 mol) ÷ 2 mol

                            X  =  4.2 Moles of Sn

Result:
           4.2 Moles of Tin are needed to react with 8.4 moles of Hydrogen Fluoride

The number of moles of tin needed to react with 8.4 moles of hydrogen fluoride are 4.2 Moles. It can be founded with the help of limiting reagent concept.

What is Limiting reagent ?

The limiting reactant (or limiting reagent) is the reactant that gets consumed first in a chemical reaction and therefore limits how much product can be formed.

Given Balance Chemical Equation ;

                                Sn (s)  +  2 HF (g)   →    SnF₂ (s)  +  H₂ (g)

According to Equation,

                      2 Moles of HF requires  =  1 Mole of Sn

Therefore,

                8.4 Moles of HF will require  =  X Moles of Sn

Solving for X,

                           X  =  (8.4 mol × 1 mol) ÷ 2 mol

                           X  =  4.2 Moles of Sn

Hence, The number of moles of tin needed to react with 8.4 moles of hydrogen fluoride are 4.2 Moles.

Learn more about Limiting reagent here ;

https://brainly.com/question/20070272

#SPJ1

How many total atoms are in 0.530 g of P2O5/12131141/dc2696ff?utm_source=registration

Answers

Final answer:

To find the number of atoms in 0.530 g of P2O5, you calculate the number of moles by dividing by the molar mass and then multiply by Avogadro's number, resulting in approximately 2.25 × 1021 atoms.

Explanation:

To determine the number of atoms in 0.530 g of P2O5, we need to calculate the number of moles and then multiply by Avogadro's number (6.022 × 1023 atoms/mol). The molecular weight of P2O5 is found by adding the atomic weights of its constituent atoms: 2P (2 × 30.973761 amu/atom) + 5O (5 × 15.9994 amu/atom), which gives us approximately 141.94 amu. Since molar mass is the mass of one mole of a substance, we can say P2O5 has a molar mass of about 141.94 g/mol.

Now, to find moles, we divide the given mass by the molar mass:
0.530 g / 141.94 g/mol = 0.00373 mol.
Next, we multiply the moles by Avogadro's number to get the total atoms:
0.00373 mol × 6.022 × 1023 atoms/mol = 2.25 × 1021 atoms.

A supervisor spends a day inspecting a nuclear plant for potential radiation leaks. She has to move throughout the plant inspecting all the equipment and machinery. She needs to take two different radiation detection devices to help ensure her safety and to find radiation leaks. She needs the results immediately. Which two devices would be the best choices for the task?

Geiger counter and scintillation counter
Geiger counter and cloud chamber
cloud chamber and scintillation counter
film badge and scintillation counter

Answers

Answer:

Geiger counter and scintillation counter

Explanation:

The Geiger counter was invented by Hans Geiger in 1908 to measure the levels of radiation in bodies and the environment, so it is one of the indispensable equipment for the inspector to detect radiation leaks in a nuclear power plant. It contains a tube with argon, which ionizes by being crossed by alpha and beta particles of radiation, closing the electric circuit and triggering the counter.

Similarly, a scintillation detector is an apparatus used to detect ionizing radiation. When something in the environment has been reached by radiation, this detector emits a small ray of light, indicating the radiation contamination.

Answer:

A. Geiger counter and scintillation counter

Explanation:

¿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

What is the volume of oxygen occupied by 2 moles at 1.3 atm pressure and 300 K? Use PV = nRT.

Answers

The  volume   of oxygen gas that occupied by  2 moles at 1.3 atm pressure and 300 k is calculated  using the ideal gas equation that is Pv =nRT

P(pressure) = 1.3 atm
R(gas  constant) =0.082 l.atm/mol.k
n (moles)= 2 moles
T(temperature) =300k
V(volume)=?

by making  the v the subject of the formula V =nRT/P

=(2 moles x 0.082 l.atm/mol.k x300 K)/ 1.3 atm= 37.85 Liters
we can use the ideal gas law equation to find the volume occupied by O₂
PV = nRT
where P - pressure - 1.3 atm x 101 325 Pa/atm = 131 723 Pa
V - volume 
n - number of moles - 2 mol 
R - universal gas constant - 8.314 Jmol⁻¹K⁻¹
T - temperature - 300 K
Substituting these values in the equation 
131 723 Pa x V = 2 mol x 8.314 Jmol⁻¹K⁻¹ x 300 K
V = 37.9 L
volume occupied is 37.9 L

The ratio of oxygen-16 and oxygen-18 isotopes in plankton fossils in deep-sea sediments can be used to determine ________.

Answers

The ratio of oxygen-16 and oxygen-18 isotopes in plankton fossils in deep-sea sediments can be used to determine past temperatures.

Answer;

-past temperatures

The ratio of oxygen-16 and oxygen-18 isotopes in plankton fossils in deep-sea sediments can be used to determine past temperatures.

Explanation;

-O-16 will evaporate more readily than O-18 since it is lighter, therefore; during a warm period, the relative amount of O-18 will increase in the ocean waters since more of the O-16 is evaporating.

-Hence, looking at the ratio of O16 to O18 in the past can give clues about global temperatures.

How many grams of the excess reactant remain after the limiting reactant is completely consumed? express your answer using two significant figures?

Answers

 4 NH3(g) + 5 O2(g) --> 4 NO(g) + 6 H2O(g) 

4 NH3(g): 4 moles @ 17.03 g/mole = 68.12 g NH3 
5 O2(g) : 5 moles @ 32 g.mole = 160 g O2 

we needed over twice the # of grams of O2 , as compared to NH3,... 
they didn't add that,... 
O2 is the limiting reagent 

find the # of grams of NH3 that react: 
4.75 g O2 @ 68.12 g NH3 / 160 g O2 = 2.02 g of NH3 actually do react 

find How many grams of the excess reactant remains : 
3.30 - 2.02 = 

your answer: 1.28 grams of NH3 remain


4 NH3(g) + 5 O2(g) 4 NO(g) + 6 H2O(g) 

In a certain experiment, 3.30 g of NH3 reacts with 4.75 g of O2. 

3.56 grams of NO form 
Final answer:

The amount of the excess reactant remaining after the limiting reactant is consumed can be found by subtracting the amount used in the reaction from the initial amount, using stoichiometry to calculate these values.

Explanation:

To determine the amount of the excess reactant remaining after the limiting reactant is completely consumed, you will need to perform some calculations. First, it is necessary to determine which reactant is the limiting one. This can be done by comparing their mole ratios in the balanced chemical equation. Then, you should calculate the amount of product that the limiting reactant can make.

Next, you can use the stoichiometry of the reaction to figure out how much of the excess reactant was needed to react with the limiting reactant. Subtract this from the total amount of the excess reactant present at the start to get the amount remaining, expressed in grams. Remember that your answer should be reported to two significant figures.

Learn more about Excess and Limiting Reactants here:

https://brainly.com/question/35053254

#SPJ2

Calculate the actual yield for the production of ammonia gas (nh3) from hydrogen and nitrogen gases if the percent yield is 68.2% and you begin with 2.00 kg of nitrogen gas

Answers

Percentage yield = (actual yield / theoretical yield) x 100%

Hence,
  actual yield = percentage yield x theoretical yield / 100

The balanced reaction equation for the production of ammonia is
N₂(g) + 3H₂(g) → 2NH₃(g)

The mass of N₂(g)  used = 2.00 kg = 2 x 10³ g
Molar mass of N₂(g) = 28 g mol⁻¹

moles (mol) = mass (g) / molar mass (g/mol)

Hence, moles of N₂(g) = 2 x 10³ g / 28 g mol⁻¹ 
                                     = 71.428 mol

Stoichiometric ratio between N₂(g) and NH₃(g) is 1 : 2

Hence, produced NH₃(g) moles = 71.428 mol x 2
                                                   = 142.856 mol

Molar mass of NH₃(g) = 17 g mol⁻¹
mass of NH₃(g) = 142.856 mol x 17 g mol⁻¹ = 2428.552 g

Hence, the theoretical yield = 2428.552 g

Then the actual yield of NH₃(g) produced = (68.2 x 2428.552 g) / 100
                                                                       = 1656.27 g

Final answer:

To determine the actual yield of ammonia gas, convert the mass of nitrogen gas to moles, calculate the theoretical yield using stoichiometry, and then apply the percent yield. The actual yield for a 68.2% percent yield from 2.00 kg of nitrogen is 1658.41 g NH3.

Explanation:

To calculate the actual yield of ammonia gas (NH3) production from nitrogen (N2) and hydrogen (H2) gases when given the percent yield and mass of nitrogen gas, we'll first need to convert the mass of nitrogen to moles, then calculate the theoretical yield of ammonia based on stoichiometry, and finally use the percent yield to find the actual yield.

Step-by-step Calculation:

Calculate moles of nitrogen: Molecular weight of N2 is 28.02 g/mol. 2.00 kg of N2 is 2000 g. Moles = 2000 g / 28.02 g/mol = 71.38 mol N2.

Using the balanced chemical equation (N2 + 3H2 → 2NH3), we see the stoichiometry is 1:2 for nitrogen to ammonia. So, moles of NH3 = 2 moles NH3/mole N2 × 71.38 mol N2 = 142.76 mol NH3.

Convert moles of NH3 to grams: Molecular weight of NH3 is 17.03 g/mol. The theoretical yield in grams = 142.76 mol NH3 × 17.03 g/mol = 2431.89 g NH3.

Calculate actual yield using the percent yield: Actual Yield = Percent Yield / 100 × Theoretical Yield = 68.2% / 100 × 2431.89 g = 1658.41 g NH3.

Therefore, the actual yield of ammonia when starting with 2.00 kg of nitrogen gas and a percent yield of 68.2% is 1658.41 g.

what will happen to the litmus strips?

Answers

If the solution is BASIC than it will turn purple but if ACIDIC it will turn pink. 

The labeled images each represent the wave patterns found in the electromagnetic wave spectrum. Which image is correctly labeled for frequency, wavelength, and radiant energy?

Answers

Answer:

C  

Low frequency                                     High frequency

Long wavelength                                 Short wavelength

Low radiant energy                              High radiant energy

Explanation:  

I took the k-12 4.04 quiz, let me know if I am wrong.

The electromagnetic spectrum is the distribution of electromagnetic radiation. The third image's low frequency, wavelength, and radiant energy are correctly labeled.

What is the electromagnetic wave spectrum?

An electromagnetic wave spectrum is the distribution of electromagnetic radiations based on frequency and wavelength. In electromagnetic radiation, energy is given by Planck's constant and frequency.

Also, the relation between the frequency and the wavelength is given as,

[tex]\nu = \rm \dfrac{c}{\lambda}[/tex]

From these relations, it can be said that the frequency is directly proportional to energy, and is inversely proportional to the wavelength.

Therefore, if on the left side low frequency, low radiant energy, and long-wavelength are present then, on the right side opposite will be observed.

Learn more about the electromagnetic spectrum here:

https://brainly.com/question/3914212

What is the oxidation number of the chromium atom in k2cro4? what is the oxidation number of the chromium atom in ? +2 +6 -3 -7 +4?

Answers

(K⁺¹)2Cr(O⁻²)4

+1*2 +x-2*4=0
2+x-8=0
x=6
Oxidation number of Cr is +6.

How to convert 1.2×10^24 atoms of magnesium into moles??

Answers

Mole Road Map:
                       ÷             ×
Mass (grams) ⇄ Moles ⇄ Particles (atoms, molecules, etc.)
                       ×             ÷
                        ↓             ↓
             Molar Mass     6.02 × 10^23 (Avogadro's number)

(1.2 × 10^24 atoms of Magnesium) ÷ (6.02 × 10^23) ≈ 2.0 mol Magnesium (according to significant figures)

To convert atoms of magnesium to moles, divide the given number of atoms by Avogadro's number. For 1.2×10^24 atoms it results in 1.99 moles of magnesium.

To convert 1.2×1024 atoms of magnesium into moles, we use Avogadro's number, which is 6.022×1023 atoms per mole. This conversion factor allows us to change the number of atoms into moles since one mole of any substance contains Avogadro's number of atoms, ions, or molecules.

Write down the number of magnesium atoms given: 1.2×1024 atoms of Mg.Use Avogadro's number as a conversion factor: 1 mole of Mg = 6.022×1023 atoms of Mg.Divide the number of atoms by Avogadro's number to find the number of moles: 1.2×1024 atoms ÷ 6.022×1023 atoms/mole = 1.99 moles of Mg.

Therefore, 1.2×1024 atoms of magnesium is equal to 1.99 moles of magnesium.

When titrating a monoprotic strong acid with a weak base at 25°c, the
a.ph will be less than 7 at the equivalence point.
b.ph will be 7 at the equivalence point.
c.titration will require more moles of the base than acid to reach the equivalence point.
d.titration will require more moles of acid than base to reach the equivalence point.
e.ph will be greater than 7 at the equivalence point?

Answers

When a strong monoprotic acid is Titrated with a weak base at 25° ;

The pH will be less than 7 at the equivalence point ( A )

A monoprotic acid donates only a single proton in a titration experiment therefore at the equivalence point in an experiment involving the reaction between the strong monoprotic acid with a weak base, all the base ions will react, while the strong acid will have some unreacted ions  ( H⁺) left in the solution.

The unreactive protons of the strong monoprotic acid present in the solution will make the solution acidic therefore the pH of the solution will be less than 7 at the equivalence point.

Hence we can conclude that when a strong monoprotic acid is titrated with a weak base at 25°, the pH will be less than 7 at the equivalence point.

Learn more : https://brainly.com/question/22763666

Final answer:

In a titration of a monoprotic strong acid with a weak base, the pH will be less than 7 at the equivalence point because the conjugate acid of the weak base will slightly ionize, rendering the solution acidic at this point.

Explanation:

When titrating a monoprotic strong acid with a weak base at 25°C, the pH at the equivalence point will be less than 7. This is because the reaction at the equivalence point produces the conjugate acid of the weak base, which slightly ionizes in solution, contributing to an acidic pH. As outlined in resources such as LibreTexts, the equivalence point's pH depends on the strength of the acid and base involved in the titration. In the case of a strong acid with a weak base, the solution will be acidic because the weak base is not strong enough to fully neutralize the strong acid. Therefore, the correct answer to the question is a. pH will be less than 7 at the equivalence point. It is also important to note that the number of moles of base and acid required to reach the equivalence point depends solely on their stoichiometry and not on their strength, meaning one mole of acid will react with one mole of base to reach the equivalence point.

Other Questions
Bill and Tom are both towing wagons. Bill's wagon weighs 10 pounds, and Tom's wagon weighs 20 pounds. Bill is pulling his wagon with twice the force that Tom is. How do the wagon speeds compare? A)Both wagons will be moving at the same speed. B)Bill's wagon is moving 4 times faster than Tom's. C)Tom's wagon is moving 4 times faster than Bill's. D)Bill's wagon is moving 2 times faster than Tom's. How many eggs are needed to make 1 dozen waffles, assuming you have enough of all other ingredients? given: 2 cups flour + 3 eggs + 1 tbs oil 4 wafflesa. 12b. 48c. none of these choices is correctd. 9e. 16? Has a nucleus and a cell wall that contains chitin After water itself, what are the two primary elements which occur in sea water? Mi mam me dio una_________ para ver una pelcula hoy. A wheelchair ramp has a slope of 1 10 . if its rise is 1 5 2 feet, what is its run? Which statement BEST describes the military structure of NATO during the Cold War? A)The organization was led exclusively by the United States. B)Member countries had input into NATO's military strategies. C)Southern European countries were prevented from taking any leadership role. D)The Soviet Union blocked NATO's attempts to increase their military strength. Which part of the brain is responsible for the highest level of thought?a. cerebellumb. brainstemc. thalamusd. cerebrum? To obtain the graph of y=(x- 8)2 shift the graph of y= x2 What lesson does lincoln say we can learn from this battle? the header, in an academic report, typically contains the authors name and the current page number true or false Mary was chosen for the starring role in the school play. Her parents do not want her to participate because they worry her grades will suffer. What should mary do ? Question 7 UnsavedEn qu te sientas en el avin? (1 point)Question 7 options:1) la tarjeta de embarque2) la aduana3) el asientoPlz help ASAP Which table shows the relationship y=-3x+2? Modernization theory and development are frequently considered to be a way to spur economic growth and a path toward what? A bag contains 10 res marbles, 15 yellow marbles, 5 green marbles, and 20 blue marbles. Five marbles are drawn from the bag. what is the approximate probability that exactly two of the five are blue The equation of a circle is (x+9)2+(y+6)2=225 .What is the center of the circle?Enter your answer in the boxes.(, ) A water skiing coach tells her team about an unusual day on the lake. Complete each sentence with the correct preterite or imperfect form of the verb in parentheses. Empez una gran tormenta de granizo! ____________________ (ser) las ocho de la noche cuando la tormenta termin. Al final, todos nosotros nos pusimos enfermos. The longest side of an obtuse triangle measure 20 cm. the two shorter sides measure x cm.and 3x sm round to the nearest tenth,what is the greatedt possible value of x In the graph, a sample of water is heated from 40 degrees Celsius to 100 degrees Celsius. Which statement correctly describes the curve?A)QR- liquid onlyRS- phase change liquid-gasST- gas onlyB)QR- liquid onlyRS- phase change liquid-solidST- solid onlyC)QR- solid onlyRS- phase change solid-liquidST- liquid onlyD)QR- phase change solid-liquidRS- liquid onlyST- phase change liquid-gas