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the rate of effusion of substance a is eight times the rate of effusion of substance b. if the molar mass of substance b is 129 g/mol, what is the molar mass of substance a?

User MaxH
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1 Answer

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Final answer:

According to Graham's law, the rate of effusion of a gas is inversely proportional to the square root of its molar mass. Using this relationship, we can determine that the molar mass of substance A is 2.01 g/mol.

Step-by-step explanation:

Graham's law states that the rate of effusion of a gas is inversely proportional to the square root of its molar mass. If the rate of effusion of substance A is eight times that of substance B, we can set up the equation:

rate of effusion of A / rate of effusion of B = sqrt(molar mass of B / molar mass of A)

Given that the molar mass of substance B is 129 g/mol, we can substitute the values and solve for the molar mass of substance A:

8 = sqrt(129 / molar mass of A)

Squaring both sides of the equation, we get:
64 = 129 / molar mass of A

Multiplying both sides by the molar mass of A, we find:
molar mass of A = 129 / 64 = 2.01 g/mol

User WildCrustacean
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