Chemistry Questions and Answers

- Alkaline solutions of pyrogallol absorb oxygen efficiently.

- Quicklime have a strong chemical affinity to absorb water.

- At room temperature, Calcium oxide (CaO) will spontaneously absorb carbon dioxide from the atmosphere.

- potassium chlorate --> KClO\(_3\)

valencies of K = +1, O = -2.

: (+1) + Cl + ( -2  X 3 atoms ) = 0

Cl + 1 - 6 = 0

Cl = 5

∴ The oxidation state of chlorine in potassium chlorate is +5

this question expresses the law of multiple proportions which states that if two elements A and B combine together to form more than one compound, the various masses of element B which combines with a fixed mass of B are in simple whole number ratios. e.g 

P [6] =  2, 4
Q [11] = 2, 8, 1
R [15] = 2, 8, 5
S [17] = 2, 8, 7

Given the above is the electronic arrangement of PQRS elements, Q will form an electrovalent bond with S

Further explanation was provided by our student by name (Odebiyi Dare D-cent) via our facebook page. Thus he says:

without argument, D is the answer cos electrovalent involves the transfer of electron. Already, Q is 11 with elect configuration of 2,8,1, i.e having 1 valency electron which is ready to be loss by that atom of element Q, also, S is 17, with electronic configuration, with 2,8,7. There the 7valence electron of S attracts that nly 1 electron to attain a stable octet structure.

Sublimation is the transition of a substance directly from the solid phase to the gas phase without passing through the intermediate liquid phase