Final answer:
Using Graham's law and the given effusion rate, we can calculate the unknown gas's molar mass, which suggests the gas could be CH4 (methane).
Step-by-step explanation:
The question pertains to the concept of gas effusion and Graham's law, which relates the rates of effusion of gases to their molar masses. Given that a gas escapes through a pinhole 0.155 times as fast as hydrogen gas (H2), and using the fact that hydrogen gas effuses four times as rapidly as oxygen gas (O2), one can use Graham's law to determine the molar mass of the unknown gas. Graham's law states that the rate of effusion of a gas (rate A) is inversely proportional to the square root of its molar mass (molar mass A).
Graham's law formula: rate of effusion of gas A / rate of effusion of gas B = sqrt(molar mass of gas B / molar mass of gas A).
By knowing the rate of effusion of hydrogen and the fact that the unknown gas effuses at 0.155 times the rate of hydrogen, we can use the formula to calculate the molar mass of the unknown gas. Let's assume the molar mass of hydrogen (H2) is 2 g/mol. By substituting the values into the formula, we can solve for the molar mass of the unknown gas.
Calculation: 1^(2) / 0.155^(2) = 2 g/mol / x g/mol, where x is the molar mass of the unknown gas.
Solving for x gives us the estimated molar mass.
The final step is to look for a gas with a molar mass that closely matches our calculation. The gas could well be CH4 (methane), which has a molar mass of approximately 16 g/mol.