HELP ME PLEASE!
1. Calculate the weight of 16.2L of pure SO2 gas at STP. (answer in grams)
a.16.2
b.31.8
c.39.5
d.46.3
e.64.1
2.A volume of 725mL of a gas is collected at 105Celsius and 745torr. The gas weighs 1.93 grams. What is the Gas?
a.Fe2
b.Ar
c.Kr
d.Xe
e.Rn
1 mol of gas at STP occupies 22.4 L. 1 mol of SO2 is 32+16+16.
Use PV = nRT for the second one. Solve for n, then use n = grams/molar mass. Use the molar mass to identify the gas from the list.
1. To calculate the weight of a gas at STP (Standard Temperature and Pressure), we need to know the molar mass of the gas.
In this case, the gas given is SO2 (Sulfur Dioxide). The molar mass of SO2 is 64.1 grams/mol.
We are given the volume of the gas (16.2L) and the condition of STP. At STP, the temperature is 0°C (or 273K) and the pressure is 1 atm (or 760 torr).
We can use the ideal gas equation to calculate the number of moles of the gas:
PV = nRT
P = pressure (in atm) = 1 atm
V = volume (in L) = 16.2 L
n = number of moles
R = ideal gas constant = 0.0821 L.atm/(mol.K)
T = temperature (in K) = 0°C + 273K = 273K
Solving for n:
n = (PV) / (RT)
= (1 atm * 16.2 L) / (0.0821 L.atm/(mol.K) * 273K)
≈ 0.6378 moles
To find the weight, we multiply the number of moles by the molar mass:
Weight = moles * molar mass
≈ 0.6378 moles * 64.1 grams/mol
≈ 40.93 grams
Therefore, the weight of 16.2L of pure SO2 gas at STP is approximately 40.93 grams.
From the given options, the closest value is option c.39.5 grams.