Homework Help: AP Chem

Posted by Anna on Tuesday, November 4, 2008 at 7:44pm.

A sample of H2 is collected by displacing 145 mL of water. The pressures of the gas and the atmosphere are equalized. The atmospheric pressure is 745 mmHg. The temperature of the water and gas are identical at 26 degrees C. How many moles of H2 have been evolved?

AP Chem - bobpursley, Tuesday, November 4, 2008 at 8:11pm
First, get the water vapor pressure at 26C. Subtract that water partial pressure from the pressure in the tube, and you have the pressure of H2, you are given the temp, and the volume.

use n=PV/RT to get moles.

Answer this Question

Related Questions

Chemistry - A student collected H2 gas in a buret by displacing water at 22.0 &...
Chemistry - A student collected H2 gas in a buret by displacing water at 22.0 &...
chemistry - 1. When gases are collected using displacement of water, some water ...
Chemistry - How would I go about doing this problem? 146 mL of wet H2 gas is ...
chemistry - 146 mL of wet H2 gas is collected over water at 29.0 degrees celsius...
Chemistry - KClO3 decomposes in the presence of MnO2 to form oxygen gas, ...
AP Chemistry - Small quantities of hydrogen gas can be prepared in the ...
AP Chem - a 4.22 gram sample of copper II sulfide was added to excess ...
Chemistry - I need help calculating the partial pressure of H2 using the ...
chemistry - A sample of hydrogen gas was collected over water at 36°C and ...

For Further Reading

First Name:
School Subject:
Answer: