Chemistry Past Questions and Answers

Which of the following represents the type of bonding present in ammonium chloride molecule?

A Ionic only
B Covalent only
C Ionic and dative covalent
D Dative covalent only

Question 687:

Which of the following is arranged in order of increasing electronegativity?

A Chlorine, aluminium, magnesium, phosphorus, sodium
B Sodium, magnesium, aluminium, phosphorus, chlorine
C Chlorine, phosphorus, phosphorous, aluminium, magnesium, sodium
D Sodium, chlorine, phosphorus, magnesium, aluminium

Question 688:

A quantity of air was passed through a weighed amount of alkaline pyrogallol. An increase in the weight of the pyrogallol would result from the absorption of?

A Nitrogen
B Neon
C Argon
D Oxygen

Question 689:

Which of the following ions is a pollutant in drinking water even in trace amounts?

A Ca2+
B Hg2+
C Mg2+
D Fe2+

Question 690:

The solubility of copper (II) tetraoxosulphate (Iv) is 75g in 100g of water at 100°C and 25g in 100g of water at 30°C. What mass of the salt would crystallize, if 50g of copper (II) tetraoxosulphate (VI) solution saturated at 100°C were cooled to 30°C ?

A 57.5
B 42.2
C 28.6
D 14.3