1997 - WAEC Chemistry Past Questions and Answers - page 1
The phenomenon observed when dust particles collide randomly in a beam of sunlight is known as
The mass number of an element is the sum of its
How many unpaired electrons are there in an atom of an element with the following electronic configuration? 1s22s22p6
Radon is used as a tracer in medical research because it
What is the most probable group of an element which is a soft, silvery white solid and reacts violently with water?
In linear molecules, the bond angle is
A sodium atom and a sodium ion have the same
If the atomic number of an element X is 11 and that of nitrogen is 7, the most likely formula of the nitride of X is
An increase in the pressure of a gas results in a decrease in its
A given volume of methane diffuses in 20 seconds. How long will it take the same volume of sulphur (IV) oxide to diffuse under the same conditions? [CH4 = 16; SO2 = 64]