The molar mass of two equally sized samples of unknown gaseous compounds is shown in the table. Molar Mass Comparison
Gas Molar Mass
A 4.00 g/mol
B 2.01 g/mol
Which statement describes the density and effusion of both gases at STP?

Effusion is the process of a gas being poured out through a hole diametrically smaller than the structural exit of the container.

A lighter gas effuses faster than a heavier gas.

Thus, gas A has a lower density and effuses slower than Gas B.

Explanation:

B. Gas A has a higher density and effuses slower than Gas B Explanation: To calculate the rate of effusion of gas, we use Graham's Law. This law states that the rate of effusion of gas is inversely proportional to the square root of the molar mass of the gas. The equation given by this law follows:

RateA = 0.70Raten

Thus Gas B would diffuse faster than gas A. As the two gases are equally sized, the y have same volume but Gas A has higher mass. Thus Gas A would be more dense than Gas B. Density

the correct answer is:

a. formation of precipitation