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11) A sample of carbon dioxide has a volume of 26 mL at 11 °C and 623 torr. How many grams of CO2 are in the sample?

User Viveksharma
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1 Answer

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Step-by-step explanation:

We have a gas sample of carbon dioxide and we know its volume, the pressure and the temperature. We can find the number of moles of that sample using the ideal gas law.

P * V = n * R * T

Where P is the pressure, V is the volume, n is the number of moles, R is the ideal gas law and T is the temperature.

R = 0.082 atm*L/(mol*K)

Since R is in atm*L/(mol*K) we have to convert the volume from mL to L, the temperature from °C to K and the pressure from torr to atm.

1000 mL = 1 L

V = 26 mL = 26 mL * 1 L/(1000 mL)

V = 0.026 L

760 torr = 1 atm

P = 623 torr = 623 torr * 1 atm/(760 torr)

P = 0.820 atm

T = (273.15 + 11 ) K

T = 284.15 K

Now we can replace these values in the formula and solve it for n to find the number of moles that are present in the sample.

P * V = n * R * T

n = P * V/(R * T)

n = 0.820 atm * 0.026 L/(0.082 atm*L/(mol*K) * 284.15 K)

n = 0.000915 mol

Finally we can convert the moles of the sample into grams using the molar mass of carbon dioxide.

molar mass of C = 12.01 g/mol

molar mass of O = 16.00 g/mol

molar mass of CO₂ = 1 * 12.01 g/mol + 2 * 16.00 g/mol

molar mass of CO₂ = 44.01 g/mol

mass of CO₂ = 0.000915 mol * 44.01 g/mo

mass of CO₂ = 0.040 g

Answer: There are 0.040 g of carbon dioxide in the sample.

User Rgoal
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