A solution contains Na₂CO₃ and NaHCO₃. 10 mL of the solution required 2.5 mL of 0.1 M H₂SO₄ for neutralisation using phenolphthalein as indicator. Methyl orange is then added when a further 2.5 mL of 0.2 M H₂SO₄ was required. The amount of Na₂CO₃ and NaHCO₃ in 1 litre of the solution is:

1. 5.3g and 4.2g

2. 3.3g and 6.2g

3. 4.2g and 5.3g

4. 6.2g and 3.3g

25 ml of a solution containing HCl and ${\mathrm{H}}_2{\mathrm{SO}}_4$ required 10 ml of a 1 N NaOH solution for neutralization. 20 ml of the same acid mixture on being treated with an excess of ${\mathrm{AgNO}}_3$ gives 0.1435 g of AgCl. The normality of HCl and normality of the ${\mathrm{H}}_2{\mathrm{SO}}_4$ are respectively

1. 0.40 N and 0.05 N

2. 0.05 N and 0.35 N

3. 0.05 N and 0.25 N

4. 0.40 N and 0.5 N 

The oxide of metal contains 40% by mass of oxygen. The percentage of chlorine in the chloride of the metal is

1) 84.7

(2) 74.7

(3) 64.7

(4) 44.7

What volume of ${\mathrm{O}}_2\left(\mathrm{g}\right)$ measured at 1 atm and 273 K will be formed by the action of 100 mL of 0.5 N KMnO₄ on hydrogen peroxide in an acid solution?

The skeleton equation for the reaction is

${\mathrm{KMnO}}_4+{\mathrm{H}}_2{\mathrm{SO}}_4+{\mathrm{H}}_2{\mathrm{O}}_2$$\to {\mathrm{K}}_2{\mathrm{SO}}_4+{\mathrm{MnSO}}_4+{\mathrm{O}}_2+{\mathrm{H}}_2\mathrm{O}$

1.  0.12 litre

2.  0.028 litre

3.  0.56 litre

4.  1.12 litre

A solution of Na₂S₂O₃ is standardized iodometrically against 0.167 g of KBrO₃. This process requires 50 mL of the ${\mathrm{Na}}_2{\mathrm{S}}_2{\mathrm{O}}_3$ solution. What is the normality of the  Na₂S₂O₃?

1. 0.2 N

2. 0.12 N

3. 0.72 N

4. 0.02 N

The ${\mathrm{NH}}_3$ evolved due to complete conversion of N from 1.12 g sample of protein was absorbed in 45 mL of 0.4 N ${\mathrm{HNO}}_3$. The excess acid required 20 mL of 0.1 N $\mathrm{NaOH}$. The % N in the sample is:

1.  8

2.  16

3.  20

4.  25

100 mL of 10% NaOH (w/V) is added to 100 mL of 10% HCl (w/V). The resultant solution becomes:

1. alkaline

2. strongly alkaline

3. acidic

4. neutral

Copper forms two oxides. For the same amount of copper, twice as much oxygen was used to form first oxide than to form second one. What is the ratio of the valencies of copper in first and second oxides?

1. 2:5

2. 1:6

3. 2:1

4. 1:2

Read the following statements (S) and Explanation (E). Choose the correct answers from the codes (1), (2), (3) and (4):

S : An element may have variable equivalent mass.

E : Such elements should possess variable valency. 

1.  S is correct but E is wrong
2.  S is wrong but E is correct
3.  Both S and E are correct and E is correct explanation of S
4.  Both S and E are correct but E is not correct explanation of S