Why is the amount of gas collected in one of the test tubes in Activity 1.7 double of the amount collected in the other? Name this gas.

Observe the diagram and write which gas is evolved from the test tube if the flame of the matchstick puts off with a sound.

A test tube of mass 10 grams closed with a cork of mass 1 gram contains some ether . When the test tube is heated the cork flies out under the pressure of the ether gas. The test tube is suspended horizontally by a weight less rigid bar of length 5 cm . What is the minimum velcoity with which the cork should fly out of the tube , so that test tube deseribing a full vertical circle about the point O . Neglect the mass of ether .

In Duma's method, the gas which is collected in Nitrometer is

Aqueous tension at 25^@C is given as 23.8 mm, If 1.5 L of nitrogen gas is collected over water at 25^@C and 735 mm Hg, find the mass of dry gas collected in the experiment.

What is the active mass of one litre of oxygen gas at NTP?