Answer : The wavelength of yellow light produced by a sodium lamp is, [tex]8.98\times 10^{-7}m[/tex]
Explanation : Given,
Frequency of radiation = [tex]3.34\times 10^{14}Hz=3.34\times 10^{14}s^{-1}[/tex]
conversion used : [tex]Hz=s^{-1}[/tex]
Formula used :
[tex]\nu=\frac{c}{\lambda}[/tex]
where,
[tex]\nu[/tex] = frequency of radiation
[tex]\lambda[/tex] = wavelength of radiation
c = speed of light = [tex]3\times 10^8m/s[/tex]
Now put all the given values in the above formula, we get:
[tex]3.34\times 10^{14}s^{-1}=\frac{3\times 10^8m/s}{\lambda}[/tex]
[tex]\lambda=8.98\times 10^{-7}m[/tex]
Therefore, the wavelength of yellow light produced by a sodium lamp is, [tex]8.98\times 10^{-7}m[/tex]
Calculate the ph of the solution resulting from the addition of 85.0 ml of 0.35 m hcl to 30.0 ml of 0.40 m aniline (c6h5nh2). kb (c6h5nh2) = 3.8 x 10-10
Answer:
pH = 0.81
Explanation:
HCl reacts with aniline, thus:
C₆H₅NH₂ + HCl → C₆H₅NH₃⁺ + Cl⁻
Moles of HCl are:
0.085L × (0.35mol HCl / L) = 0.02975mol HCl
Moles of aniline are:
0.030L × (0.40mol HCl / L) = 0.012mol aniline
Thus, after reaction, will remain:
0.02975mol - 0.012mol = 0.01775mol HCl
Moles of HCl in solution are equal to moles of H⁺, thus, moles of H⁺ are: 0.01775mol H⁺
As total volume is 85.0mL + 30.0mL = 115.0mL ≡ 0.115L
0.01775mol / 0.115L = 0.1543M
pH of solution = -log[H⁺]
pH = -log 0.1543M
pH = 0.81
Answer:
pH = 0.81
Explanation:
Step 1: Data given
Volume of a 0.35 M HCl solution = 85.0 mL
Volume of a 0.40 M aniline solution = 30.0 mL
Kb of aniline = 3.8 * 10^-10
Step 2: The balanced equation
C6H5NH2 + HCl → C6H5NH3+ + Cl-
Step 3: Calculate moles
Moles = molarity * volume
Moles HCl = 0.35 M * 0.085 L
Moles HCl = 0.02975 moles
Moles aniline = 0.40 M * 0.030 L
Moles aniline = 0.012 moles
Step 4: Calculates limiting reactant
Aniline is the limiting reactant. It will completely be consumed (0.012 mole)
HCl is in excesS. There will react 0.012 moles. There will remain 0.02975 - 0.012 = 0.01775 moles
Step 5: Calculate molarity HCl
Molarity HCl = moles HCl / total volume
Molarity HCl = 0.01775 moles / 0.115 L
Molarity HCl = 0.154 M
Step 6: Calculate pH
pH = -log[H+]
pH = -log[0.154]
pH = 0.81
What is the molar mass of acetylsalicylic acid (Aspirin)? (HC₉H₇O₄)
Answer:
180 g/mol
Explanation:
M(HC₉H₇O₄) = M(H) + 9M(C) + 7M(H) + 4M(O) = 1+ 9*12 +7*1 + 4*16= 180
The molar mass of Aspirin (C9H8O4) is calculated as 180.17 g/mol, by summing the individual contributions of the atomic masses of carbon, hydrogen, and oxygen.
Explanation:The molar mass of acetylsalicylic acid, commonly known as Aspirin, can be calculated by adding the atomic masses of its constituent atoms. Aspirin has the molecular formula C9H8O4. To calculate the molar mass, we sum the atomic masses as follows:
Carbon (C): 12.01 g/mol x 9 atoms = 108.09 g/molHydrogen (H): 1.01 g/mol x 8 atoms = 8.08 g/molOxygen (O): 16.00 g/mol x 4 atoms = 64.00 g/molAdding these contributions together, we get:
Molar mass of Aspirin (C9H8O4) = 108.09 + 8.08 + 64.00 = 180.17 g/mol
This value is slightly different from the reference value of 180.15 g/mol, likely due to rounding differences in the atomic masses used.
A mutation occurs in a cell. Which sequence best represents the correct order of the events involved for this mutation to affect the traits expressed by this cell
Answer: A change in the sequence of DNA bases--> Joining amino acids in sequence --> Appearance of characteristics
Explanation:
A mutation is a permanent shift or change from the normal DNA sequence that makes up a gene and affect traits which makes the sequence becomes different from what is commonly found in people. Mutations vary from distortion of a single DNA building block to a large segment of a chromosome.
When mutation occurs in a cell, for the mutation to affect the traits expressed by the particular cell, it must follow this sequence directly:
A change in the sequence of DNA bases--> Joining amino acids in the sequence --> Appearance of characteristics.
The correct sequence is: D) A change in the sequence of DNA bases --->Joining amino acids in sequence ----> Appearance of characteristic
The correct sequence for a mutation to affect cell traits is: a change in the DNA sequence, then joining amino acids in sequence, and finally the appearance of the characteristic.
This order ensures that DNA mutations lead to altered proteins, which result in changed traits.For a mutation to affect the traits expressed by a cell, the events follow a specific sequence.The correct sequence is:
A change in the sequence of DNA basesJoining amino acids in sequenceAppearance of characteristicThis sequence follows the principle that mutations in DNA alter the nucleotide sequence, which in turn changes the amino acid sequence in the proteins produced.
These protein changes can then manifest as different traits or characteristics in the organism.For example, in the case of Sickle Cell Anemia, a single base-pair substitution in the hemoglobin gene results in a different amino acid sequence, altering the shape and function of red blood cells.
Correct question is: A mutation occurs in a cell. Which sequence best represents the correct order of the events involved for this mutation to affect the traits expressed by this cell?
A) a change in the sequence of DNA bases ----> joining amino acids in sequence appearance of characteristic
B) joining amino acids in sequence ---> a change in the sequence of DNA bases appearance of characteristic
C) appearance of characteristic rarr joining amino acids in sequence ---> a change in the sequence of DNA bases
D) a change in the sequence of DNA bases ----> appearance of characteristic ---> joining amino acids in sequence
The decomposition of sulfonyl chloride, SOCl2 is a first order reaction with a half life of 8.75 hours. Calculate the concentration of SOCl2 after 17.0 hours have passed in an experiment where the initial concentration of sulfonyl chloride was .0837M.
Answer:
[tex][SOCl_2]=0.0218M[/tex]
Explanation:
The equations for a first order reaction are:
[tex]\dfrac{d[A]}{dt}=-k[A][/tex]
[tex][A]=[A_0]e^{-kt}[/tex]
[tex]t\frac{1}{2}=\dfrac{\ln 2}{k}[/tex]
1. Calculate the constant of reaction, k:
Use the equation
[tex]t\frac{1}{2}=\dfrac{\ln 2}{k}[/tex]
[tex]8.75h=\dfrac{\ln 2}{k}[/tex]
[tex]k=\dfrac{\ln 2}{8.75h}[/tex]
[tex]k\approx 0.0792168h^{-1}[/tex]
2. Calculate the concentration after 17.0 hours
Use the equation
[tex][A]=[A_0]e^{-kt}[/tex]
[tex][SOCl_2]=0.0837M\cdot e^{-0.0792168h^{-1}\times 17.0h}[/tex]
[tex][SOCl_2]=0.0218M[/tex]
A gas has a pressure of 410 atm and a volume of 32 L. At what pressure would the volume of the gas change to 28L?
Answer:
At 468.57 atm pressure the gas volume would change to 28 L.
Explanation:
Boyle's law states that the pressure of a gas in a closed container is inversely proportional to the volume of the container, when the temperature is constant.
This law can be expressed mathematically as:
P · V = k
where P is pressure, V is volume and k is a constant.
This formula can be used to determine the change in pressure or volume during an isothermal transformation (i.e. the temperature is constant) as follows:
P1 · V1 = P2 · V2
In this case,
P1= 410 atmV1= 32 LP2= ?V2= 28 LReplacing:
410 atm*32L= P2*28 L
Solving:
[tex]P2=\frac{410 atm*32 L}{28L}[/tex]
P2=468.57 atm
At 468.57 atm pressure the gas volume would change to 28 L.
What is the volume of 2.3 mol of helium at 17 C and 0.89 atm? Assume helium behaves as an ideal gas.
Answer:
39.446L
Explanation:
since helium is ideal gas, we can use PV = nRT
P = pressure
V = volume
n = moles
R = gas constant
T = temperature in Kelvin
we are solving for V
V = [tex]\frac{nRT}{P}[/tex]
C to K temp transfer: K = C + 273, so K = 290 since C = 17
our gas constant is 0.08206 atm L/mol K, this gas constant r will change depending on what unit of pressure you are using (mmHg, atm, etc).
plug and chug
V = [tex]\frac{(2.3mol)(290K)(\frac{0.08206 atmL}{molK}) }{1 atm}[/tex]
canceling out units
V = [tex]\frac{2.3 * 209 * 0.08206L}{1}[/tex] = 39.446
Given the equation I = Q/t, solve for t.
Answer: [tex]t=\frac{Q}{I}[/tex]
Explanation:
[tex]I=\frac{Q}{t}[/tex]
Multiply by t on both sides.
[tex]t*I=\frac{Q}{t}*t[/tex]
[tex]tI=Q[/tex]
Now divide by I to isolate t.
[tex]\frac{tI}{I}=\frac{Q}{I}[/tex]
[tex]t=\frac{Q}{I}[/tex]
Final answer:
To solve for time t in the equation I = Q/t, multiply both sides by t to get t × I = Q, and then divide both sides by I to obtain[tex]t=\frac{Q}{I}[/tex].
Explanation:
To solve the equation, [tex]I= \frac{Q}{t}[/tex] for the variable t, you need to isolate t on one side of the equation. This can be done by rearranging the equation algebraically. Here's how it is done step-by-step:
Multiply both sides of the equation by t to get t × I = Q.
Next, divide both sides of the equation by I to solve for t, so we have [tex]t=\frac{Q}{I}[/tex].
Through these steps, we've successfully isolated t and found that the time (t) is equal to the charge (Q) divided by the current (I).
How many miles of C5H12 are there in 362.8 grams of the compound?
Answer:
5.03 moles
Explanation:
Find the molar mass of C5H12 and you will get 72.17 g/mol
Next to find the number of moles, you divide 362.8 by the molar mass and you get
(362.8 g)/(72.17 g/mol)= 5.03 moles
A compound that can act as an acid or a base is referred to as
Answer:
An amphoteric substance
Explanation:
Answer:
An atmospheric substance
For example is an aluminum hydroxide is atmospheric because it can act as a base and neutralize strong acids
Balance each of the chemical equations below. (Some equations may already be
in balance.) In the space to the right, classify the reaction as a synthesis, decomposition,
single replacement, or double replacement reaction.
A. ___ AgNO3 + ___ KCl⇒ ___ AgCl + ___ KNO3 _______________________
B. ___ H2O + ___ SO3 ⇒ ___ H2SO4 _______________________
C. ___ KI + ___ Cl2 ⇒ ___ KCl + ___ I2 _______________________
D. ___ NaHCO3 ⇒___ Na2CO3 + ___ H2O + ___ CO2 _______________________
E. ___ Zn + ___ HCl ⇒ ___ ZnCl2 + ___ H2 _______________________
F. ___ BaCl2 + ___ Na2SO4 ⇒ ___ BaSO4 + ___ NaCl _______________________
G. ___ C3H8 + ___ O2 ⇒ ___ CO2 + ___ H2O _______________________
H. ___ Al + ___ CuCl2 ⇒ ___ AlCl3 + ___ Cu _______________________
i will give 80 points and brainliest answer to the first one that answers
Answer:
A. 1 AgNO3 + 1 KCl ⇒ 1 AgCl + 1 KNO3 double replacement
B. 1 H2O + 1 SO3 ⇒ 1 H2SO4 synthesis
C. 2 KI + 1 Cl2 ⇒ 2 KCl + 1 I2 single replacement
D. 2 NaHCO3 ⇒ 1 Na2CO3 + 1 H2O + 1 CO2 decomposition
E. 1 Zn + 2 HCl ⇒ 1 ZnCl2 + 1 H2 single replacement
F. 1 BaCl2 + 1 Na2SO4 ⇒ 1 BaSO4 + 2 NaCl double displacement
G. 1 C3H8 + 5 O2 ⇒ 3 CO2 + 4 H2O combustion
H. 2 Al + 3 CuCl2 ⇒ 2 AlCl3 + 3 Cu single displacement
Explanation:
Use algebra to make sure you have the same amount of each element on each side (Reactants and Products) and only change the coefficients of the compounds and elements!
double displacement: AB + CD ⇒ AD + CB
single replacement: AB + C ⇒ A + CB
decomposition: A ⇒ B + C
synthesis: A + B ⇒ C
combustion: any reaction that involve oxygen and don't follow any of the previous reactions
To balance a chemical reaction equation, the number of atoms of each element on both sides of the reaction equation must be the same.
A chemical reaction equation has a right hand side (reactants side) and a left hand side (products side). The reactants combine to give the products. The number of atoms of each element on the reactants side must be exactly the same as the number of atoms of the same element on the products side.
The balanced chemical reaction equation for each of the reactions is shown below;
AgNO3 + KCl ------>AgCl + KNO3 double replacement reactionH2O + SO3 -------> H2SO4 synthesis reaction2KI + Cl2 ------> 2 KCl + I2 single replacement reaction 2NaHCO3 ----> Na2CO3 + CO2 + H2O decomposition reactionZn + 2HCl -----> ZnCl2 + H2 single replacement reaction BaCl2 + Na2SO4 ------> 2NaCl + BaSO4 double replacement reactionC3H8 + 5O2 ------> 3CO2 + 4H2O Combustion reaction2Al + 3CuCl2 -----> 2AlCl3 + 3Cu single replacement reactionIf there is no molar coefficient written in front of any of the species then the molar is 1.
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How many grams of sodium bromide must be dissolved in 400.0 g of water to produce a 0.500 molal solution?
Answer:
The answer is 20.6 grams.
Explanation:
Molality describes the concentration of a solution. It can be defined as the number of moles of a solute dissolved in 1 kilogram of solvent. Then it is equal to the moles of solute (the substance that dissolves) divided by the kilograms of solvent (the substance used to dissolve):
[tex]Molality=\frac{number of moles of solute}{kilogram of solvent}[/tex]
The molality is expressed in units ([tex]\frac{moles}{kg}[/tex]).
So, you can apply the following rule of three with the solution being 0.5 molal: if in 1 kg of solution there are 0.5 moles of solute, in 0.4 kg (400 g, being 1kg = 1000g) how many moles of solute are there?
[tex]moles=\frac{0.4 kg*0.5 moles}{1 kg}[/tex]
moles=0.2 moles
Now, you know:
Na: 23 g/moleBr: 80 g/moleThen, The molar mass of sodium bromide NaBr is
NaBr= 23 g/mole + 80 g/mole= 103 g/mole
Now a new rule of three applies, if in 1 mole of sodium bromide there are 103 grams, in 0.2 mole how much mass is there?
[tex]mass=\frac{0.2 moles*103 grams}{1 mole}[/tex]
mass= 20.6 grams
The answer is 20.6 grams.
A sample of gas occupies 280 mL when the pressure is 560.00 mm Hg . If the temperature remains constant , what is the new pressure if the volume changes to 560.0 mL?
Answer : The new pressure if the volume changes to 560.0 mL is, 280 mmHg
Explanation :
According to the Boyle's, law, the pressure of the gas is inversely proportional to the volume of gas at constant temperature and moles of gas.
[tex]P\propto \frac{1}{V}[/tex]
or,
[tex]P_1V_1=P_2V_2[/tex]
where,
[tex]P_1[/tex] = initial pressure = 560.00 mmHg
[tex]P_2[/tex] = final pressure = ?
[tex]V_1[/tex] = initial volume = 280 mL
[tex]V_2[/tex] = final volume = 560.0 mL
Now put all the given values in the above formula, we get:
[tex]560.00mmHg\times 280 mL=P_2\times 560.0 mL[/tex]
[tex]P_2=280mmHg[/tex]
Therefore, the new pressure if the volume changes to 560.0 mL is, 280 mmHg
What is the molar mass of Na(C2 H3 O2)?
Answer:
The answer to your question is 82g
Explanation:
Data
Molecule: Sodium acetate Na(C₂H₃O₂)
Molar mass = ?
Process
Look for the atomic mass of each element, multiply this number by the subscript and add the results.
Sodium = 23 g
Carbon = 2 x 12 = 24 g
Hydrogen = 1 x 3 = 3 g
Oxygen = 2 x 16 = 32 g
Sum up the result
Molar mass = 23 + 24 + 3 + 32
= 82 g
A 48.4-g sample of glucose (a nondissociated, nonvolatile solute with the formula c6h12o6) is dissolved in 151.2 g of water. what is the vapor pressure of this solution at 100°c?
Answer:
Vapor pressure of solution is 736mmHg
Explanation:
Vapor pressure of an ideal solution follows Raoult's law:
[tex]P_{solution} = X_{solvent}P_{solvent}[/tex]
Where P is vapor pressure and X is mole fraction
Moles of glucose are:
48.4g × (1mol / 180.156g) = 0.2687mol glucose
Moles of water:
151.2g × (1mol / 18.1g) = 8.354 mol water
Thus, mole fraction of water (Solvent) is:
8.354 mol / (8.354 mol + 0.2687mol) = 0.9688
Vapor pressure of a solvent at boiling point is equal to atmospheric pressure (760mmHg). Replacing in Raoult's law:
[tex]P_{solution} = 0.9688*760mmHg[/tex]
Vapor pressure of solution is 736mmHg
The vapor pressure of the solution will be "736 mmHg".
Vapor pressureAccording to the question,
Sample of glucose = 48.4 g
Mass of water = 151.2 g
Temperature = 100°C
Now,
Moles of glucose will be:
= 48.4 × ([tex]\frac{1 \ mol}{180.156}[/tex])
= 0.2687 mol
Moles of water will be:
= 151.2 × ([tex]\frac{1 \ mol}{18.1}[/tex])
= 8.354 mol
Water's moles fraction will be:
= [tex]\frac{Moles \ of \ water}{Moles \ of \ water +Glucose}[/tex]
By substituting the values,
= [tex]\frac{8.354}{8.354+0.2687}[/tex]
= 0.9688
hence,
By using Raoult's Law,
→ [tex]P_{solution}[/tex] = [tex]X_{solvent} P_{solvent}[/tex]
By substituting the values,
= 0.9688 × 760
= 736 mmHg
Thus the above solution is correct.55
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Consider the reaction below.
HCIO3 + NH3 → NH4+ + CIO3-
Which is a base-conjugate acid pair?
NH3 and CIO3-
NH3 and NH4+
HCIO3 and NH3
HCIO3 and NH4+
Answer:
NH3 and NH4+
Explanation:
NH4+ is the conjugate acid of the base NH3.
The example of base-conjugate acid pair is B. NH3 and NH4+.
What is a base-conjugate acid pair?A base-conjugate acid pair simply means a pair that consist of two substances that only differ by the presence of a proton (H+).
In this case, the example of base-conjugate acid pair is NH3 and NH4+ because bNH4+ is the conjugate acid of the base NH3.
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A 9.80 L container holds a mixture of two gases at 55 ° C. The partial pressures of gas A and gas B, respectively, are 0.298 atm and 0.589 atm. If 0.130 mol of a third gas is added with no change in volume or temperature, what will the total pressure become?
Answer:
1.24 atm is the new pressure
Explanation:
We may solve this question with the Ideal Gases Law that must be used, twice. → P . V = n . R . T
Total pressure = Partial pressure of gas A + Partial pressure of gas B
Total pressure = 0.298 atm + 0.589 atm → 0.887 atm
We convert the T° to Absolute value → 55°C + 273 = 328K
0.887 atm . 9.80L = n . 0.082 . 328K
(0.887 atm . 9.80L) /(0.082 . 328K) = 0.323 moles
These are the moles from the initial mixture, but we add 0.130 moles
Total new moles are 0.323 + 0.130 = 0.453 moles
P = (0.453 mol . 0.082 . 328K) / 9.80L
P = 1.24 atm
Notice, that the pressure was increased. As we add a third gas, the pressure is correctly increased because the molecules from all of the gases collide more with the walls of the vessel.
which solution contains phenolphthalein pink?
The heat of combustion of propane, C3H8, is 2220 kJ/mol. The specific heat of copper is 0.385 J/g°C. How many grams of propane must be burned to raise the temperature of a 10.0 kg block of copper from 25.0°C to 65.0°C, assuming none of the heat is lost to the surroundings?
Answer:
Explanation:
q = (mass) (temp change) (specific heat)
q = (10000 g) (40 °C) (0.385 J/g⋅°C) = 154000 J = 154 kJ
154 kJ / 2220 kJ/mol = 0.069369369 mol
0.069369369 mol times 44.0962 g/mol = 3.06 g (to three sig figs)
answer choice 4
The heat of combustion ([tex]\Delta[/tex]Hc0) is the amount of energy released as heat when a compound completely burns with oxygen under standard conditions.
3.05988g. grams of propane must be burned to raise the temperature of a 10.0 kg block of copper from 25.0°C to 65.0°C.
What is meant by heat of combustion?The heat of combustion ([tex]\Delta[/tex]Hc0) is the amount of energy released as heat when a compound completely burns with oxygen under standard conditions. In most cases, a hydrocarbon reacts with oxygen to produce carbon dioxide, water, and heat.The heat of combustion of a substance is the amount of energy released when a specific amount (e.g., 1 mol, 1g, 1 L) of the substance completely burns in oxygen. The heat of combustion is typically measured at 298K (25 C) and 101.3kPa.The energy released when a substance X completely burns with an excess of oxygen under standard conditions (25°C and 1 bar). It is the inverse of the enthalpy change for the combustion reaction in thermodynamic terms.q=m*c*(change of T)
q=10000g(0.385J/g*c)*(65.0C-25.0C)or (338.2 K-298.2K)
q=154000J
154000J*(1 mol/2220 KJ)=69.36936 x [tex]10 ^-3[/tex] mol
here's where I'm stuck
0.069369 mol
and i know that for every 1 mol there is 44.11g of C3H8.
0.069369 mol* (44.11g C3H8)/1mol = 3.05988g.
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75.0 g of sodium completely reacts with iron III Carbonate. How many grams of sodium carbonate are formed?
Answer:
mass = 172.78 grams Na₂CO₃(s) formed
Explanation:
6Na°(s) + Fe₂(CO₃)₃ => 3Na₂CO₃(s) + 2Fe°(s)
moles Na°(s) = 15g/23g/mol = 3.26 mole Na°(s)
From stoichiometry of reaction equation, 3.26 mole Na°(s) => 3/6(3.26) mole Na₂CO₃(s) = 1.63 mole Na₂CO₃(s) x 106 g/mole = 172.78 grams Na₂CO₃(s)
Some farmers leave a strip of land around the edge of each field which they do
not spray with chemicals.
Suggest two reasons why this will lead to an increase in the number of partridges
on these farms.
Answer:
There are no caterpillars on the oak tree in winter. ... Some farmers spray their crops with chemicals to kill insects and weeds. ... Some farmers leave a strip of land around the edge of each field which they do not spray with chemicals.
Explanation:
Hope this help ;)
Farmers leaving unsprayed strips of land can increase partridge numbers due to safer habitats free from pesticides and better provision of food and nesting areas.
Explanation:Leaving a strip of land around the edge of each field unsprayed with chemicals will likely increase the number of partridges on these farms for two main reasons.
Pesticide avoidance provides a safe habitat for partridges and other wildlife, reducing mortality rates from chemical exposure. Habitat provision enhances the availability of food sources and nesting areas, encouraging the proliferation of partridge populations.Crop rotation is also a practice that allows farmers to improve soil fertility, diversify their crops, and reduce pesticide costs by breaking the cycle of weeds, insects, and diseases naturally.
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Juanita sticks a nail to the end of a bar magnet. She then sticks a second nail to the first, then another to that one, and so on. When she gets to the seventh nail, it falls off the sixth nail.
Which statement best describes the forces acting on the seventh nail?
A. The force of magnetism is equal to the force of gravity.
B. The force of gravity is stronger than the force of magnetism.
C. The force of magnetism is stronger than the force of gravity.
Explanation:
answer is b
A balloon containing helium gas expands from 230
mL to 860 mL as more helium is added. What was
the initial quantity of helium present if the
expanded balloon contains 3.8 x 10-4 mol,
assuming constant temperature and pressure?
Which of the variables are known?
DONE
The answer for the following problem is mentioned below.
Therefore the final moles of the gas is 14.2 × [tex]10^{-4}[/tex] moles.Explanation:
Given:
Initial volume ([tex]V_{1}[/tex]) = 230 ml
Final volume ([tex]V_{2}[/tex]) = 860 ml
Initial moles ([tex]n_{1}[/tex]) = 3.8 ×[tex]10^{-4}[/tex] moles
To find:
Final moles ([tex]n_{2}[/tex])
We know;
According to the ideal gas equation;
P × V = n × R × T
where;
P represents the pressure of the gas
V represents the volume of the gas
n represents the no of the moles of the gas
R represents the universal gas constant
T represents the temperature of the gas
So;
V ∝ n
[tex]\frac{V_{1} }{V_{2} }[/tex] = [tex]\frac{n_{1} }{n_{2} }[/tex]
where,
([tex]V_{1}[/tex]) represents the initial volume of the gas
([tex]V_{2}[/tex]) represents the final volume of the gas
([tex]n_{1}[/tex]) represents the initial moles of the gas
([tex]n_{2}[/tex]) represents the final moles of the gas
Substituting the above values;
[tex]\frac{230}{860}[/tex] = [tex]\frac{3.8 * 10^-4}{n_{2} }[/tex]
[tex]n_{2}[/tex] = 14.2 × [tex]10^{-4}[/tex] moles
Therefore the final moles of the gas is 14.2 × [tex]10^{-4}[/tex] moles.
Answer:
1.0 × 10-4 mol
Or just A. The first one
Explanation:
Just did it on eg
If 0.545J of heat leads to a 0.892 degree C change, what mass of water is present?
Answer:
I got .146 g of water
Explanation:
Refer to this equation:
Q= mcΔt
Q= .545 J
c= 4.186 J/g
Δt= .892
plug in values:
.545 J = m(4.186 J/g)(.892°C)
simplify:
.545 J = m(3.734 J/g°C)
.146 g
A concentration cell consists of two Sn/Sn2+ half-cells. The electrolyte in compartment A is 0.10 M Sn(NO3)2. The electrolyte in B is 0.87 M Sn(NO3)2. Which half-cell houses the cathode? What is the voltage of the cell? Cathode: half-cell A half-cell B Voltage of cell: V
Answer:
In compartment A, the solution will be concentrated with respect to compartment B, however, over time both compartments will have the same concentration. In compartment B it houses the cathode.
the voltage of the cell is 0.0315 V
Explanation:
Given:
Electrolyte in compartment A is 0.10 M
Electrolyte in compartment B is 0.87 M
Questions:
Which half-cell houses the cathode?
What is the voltage of the cell, V = ?
In both compartments, the reactions are:
A: Sn → Sn²⁺ + 2e⁻
B: Sn²⁺ + 2e⁻ → Sn
In compartment A, the solution will be concentrated with respect to compartment B, however, over time both compartments will have the same concentration. In compartment B it houses the cathode.
The voltage of the cell
[tex]V=E_{in} -\frac{0.0592}{nlog(C_{A} /C_{B} )}[/tex]
Here
n = 2 due the two electrons transferred
Ein = 0
Substituting values:
[tex]V=0-\frac{0.0592}{2*log(0.1/0.87)} =0.0315V[/tex]
A gas sample containing 1.45 mol at 25°C exerts a pressure of 408 torr. Some gas is added to the same container, and the temperature is increased to 50.°C. If the pressure increases to 800. torr, how many moles of gas were added to the container? Assume a constant-volume container.
Answer:
It were added 1.17 moles of gas
Explanation:
We use the Ideal Gases Law to propose both situations:
P . V = n . R . T
For initial situation → P₁ . V₁ = n₁ . R . T₁
For the second situation → P₂ . V₂ = n₂ . R . T₂
R is a constant and V remains constant, so we cancel from the equations.
(n₁ . T₁) / P₁ = (n₂ . T₂) / P₂
Notice that n₂ = n₁ + x where n₁ = 1.45 moles.
Let's make the conversions for the units
25°C + 273 = 298 K (T₁) and 50°C + 273 = 323K (T₂)
408 Torr . 1 atm / 760 Torr = 0.537 atm (P₁)
800 Torr . 1 atm / 760 Torr = 1.05 atm (P₂)
Let's replace and find the x
(1.45 mol . 298K) / 0.537 atm = (( x + 1.45mol) . 323K) / 1.05 atm
(1.45 mol . 298K) / 0.537 atm . 1.05 atm = ( x + 1.45mol) . 323K
845 mol. K = 323 x K + 468.35 mol.K
845 mol.K - 468.35 mol.K = 323 x K
376.65 mol.K / 323 K = x
1.17 mol = x
HgO + Cl2 → HgCl + O2
A. Double Replacement
B. Single Replacement
C. Combustion
D. Decomposition
E. Synthesis
Answer:
B. Single Replacement
Explanation:
Single replacement:
It is the reaction in which one elements replace the other element in compound.
AB + C → AC + B
Chemical equation:
2HgO + Cl₂ → HgCl + O₂
This is the single replacement reaction. In this reaction chlorine replace the oxygen from mercury oxide and form mercury chloride.
Other options are incorrect because,
Decomposition reaction:
It is the reaction in which one reactant is break down into two or more product.
AB → A + B
Synthesis reaction:
It is the reaction in which two or more simple substance react to give one or more complex product.
A + B → AB
Double replacement:
It is the reaction in which two compound exchange their ions and form new compounds.
AB + CD → AC +BD
What is the concentration of a calcium hydroxide solution, if 35.00 mL of the base is completely neutralized by 12.0 mL of 0.0338 M HCl?
Answer:
0.00579 M
Explanation:
Concentration of acid CA= 0.0338 M
Volume of acid VA= 12.0mL
Concentration of base CB= ??????
Volume of base VB= 35.00mL
Now we must write the equation of the reaction:
Ca(OH)2(aq) + 2HCl(aq) ------> CaCl2(aq) + 2H2O(l)
We can now write the number of moles of acid and base
Number of moles of acid NA= 2
Number of moles of base NB= 1
From:
CAVA/CBVB = NA/NB
CAVANB = CBVBNA
CB= CA VA NB/ VB NA
CB=0.0338 × 12.0 × 1/ 35.0 × 2
CB= 0.00579 M
How many liters of 1.5 M potassium permanganate could be made if 152 g of the solute are available?
Answer:
0.64 L
Explanation:
Recall that
n= CV where n=m/M
Hence:
m/M= CV
m= given mass of solute =152g
M= molar mass of solute
C= concentration of solute in molL-1 = 1.5M
V= volume of solute =????
Molar mass of potassium permanganate= 158.034 g/mol
Thus;
152 g/158.034 gmol-1= 1.5M × V
V= 0.96/1.5
V= 0.64 L
Answer:
The volume of KMnO4 produced is = 16,013.7 Litres
Explanation:
Concentration = mass (in moles) ÷ volume (in litres)
1g = 158.03 moles
152g = 24,020.56 moles of KMnO4
1.5 M = mass (in moles) ÷ vol
⇒ Volume = [tex]\frac{24,020.56} {1.5}[/tex]
= 16,013.7 Litres
What is the molarity of a 2.0L solution that was made up with 4.0 moles of NaCl?
Answer:
[NaCl]: 2M
Explanation:
This solution is made of NaCl therefore:
Our solute is NaCl
Moles of solute: 4
Our solution's volume is 2L
Molarity are the moles of solute contained in 1L of solution (mol/L)
[NaCl]: 4 mol /2L = 2M
We can also make a rule of three:
In 2 L we have 4 moles of solute
So, In 1 L we must have (1 . 4) /2 = 2 M
The molarity of the solution is 2.0 M (moles per liter).
To determine the molarity of a solution, one must use the formula:
[tex]\[ \text{Molarity (M)} = \frac{\text{Number of moles of solute (n)}}{\text{Volume of solution (V)}} \][/tex]
Given that the solution contains 4.0 moles of NaCl (solute) and has a total volume of 2.0 liters, we can plug these values into the formula:
[tex]\[ \text{Molarity (M)} = \frac{4.0 \text{ moles}}{2.0 \text{ L}} \] \[ \text{Molarity (M)} = 2.0 \text{ M} \][/tex]
Therefore, the molarity of the solution is 2.0 moles per liter. This means that there are 2.0 moles of NaCl dissolved in every liter of the solution.
The molar enthalpy of vaporization of water is 40.79 kJ/mol, and the molar enthalpy of fusion of ice is 6.009 kJ/mol. The molar mass of water is 18.02 g/mol. How much energy is absorbed when 30.3 g of liquid water boils
Answer : The amount of energy absorbed is, 81.2 kJ
Explanation :
The process involved in this problem are :
[tex](1):H_2O(l)(0^oC)\rightarrow H_2O(l)(100^oC)\\\\(2):H_2O(l)(100^oC)\rightarrow H_2O(g)(100^oC)[/tex]
The expression used will be:
[tex]Q=[m\times c_{p,l}\times (T_{final}-T_{initial})]+[m\times \Delta H_{vap}][/tex]
where,
[tex]Q[/tex] = heat required for the reaction = ?
m = mass of liquid = 30.3 g
[tex]c_{p,l}[/tex] = specific heat of liquid water = [tex]4.18J/g^oC[/tex]
[tex]\Delta H_{vap}[/tex] = enthalpy change for vaporization = [tex]40.79kJ/mol=\frac{40790J/mol}{18.02g/mol}=2263.6J/g[/tex]
Now put all the given values in the above expression, we get:
[tex]Q=[30.3g\times 4.18J/g^oC\times (100-0)^oC]+[30.3g\times 2263.6J/g][/tex]
[tex]Q=81252.48J=81.2kJ[/tex]
Therefore, the amount of energy absorbed is, 81.2 kJ