Problem page a gas made up of atoms escapes through a pinhole 0.225 times as fast as h2 gas. write the chemical formula of the gas.

To determine what gas is this, we use Graham's Law of Effusion where it relates the rates of effusion of gases and their molar masses. We do as follows:

r1/r2 = √(M2 / M1)

Let 1 be the the unkown gas and 2 the H2 gas.

r1/r2 = 0.225
M2 = 2.02 g/mol

0.225 = √(2.02 / M1)
M1 = 39.90 g/mol

From the periodic table of elements, most likely, the gas is argon.

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