Chemistry Questions

Which of the following causes acid rain?

I. SO2

II. NO2

III. CO2

Which  of  the  following  substances  cause temporary hardness in water?

1. Mg(HCO3)2

2. Ca(HCO3)2

3. CaCl2

4. MgSO4

Which of the following statements is INCORRECT?

I) Bleaching powder is a pale yellow powder

II) Dry NH3 gas turns red litmus blue

III) The pH of rain water is nearly 7

IV) The pH of acid rain is nearly 5.6

Valency of an element depends on which of the following?

I. Number of losing electron

II. Number of gaining electron

III. Number of sharing electron

Isobars are atoms of different chemical elements that have ______.

Match List -I with List -II and select the correct answer using the code given below the Lists :

            List -I                               List-II

(Compound/Molecule)         (Shape of Molecule)

A. CH3F                            1. Trigonal planar

B. HCHO                           2. Tetrahedral

C. HCN                             3. Trigonal pyramidal

D. NH3                             4. Linear

Which of the following pairs is INCORRECT?

I. Haematite : Iron

II. Pitchblende : Copper

III. Monazite : Thorium

In a combination reaction there can be ______.

I. two or more than two reactants

II. two or more than two products

III. only one product