The amount of water vapour produced by the complete combustion of 16 g of methane is:

1. 9 g
2. 18 g
3. 36 g
4. 27 g

The number of significant figures in 50000.020 × 10^–3 is:

What is the ratio of the number of molecules of oxygen to nitrogen in a specific gaseous mixture if their mass ratio is 1:4?

0.1 mole of carbohydrate with empirical formula CH₂O contains 1 g of hydrogen. What is its molecular formula?
1. C₅H₁₀O₅
2. C₆H₁₂O₆
3. C₄H₈O₄
4. C₃H₆O₃

An organic compound contains 80 % (by wt.) carbon and the remaining percentage of hydrogen. The empirical formula of this compound is:
[Atomic wt. of C is 12, H is 1] 
1. CH₃
2. CH₄
3. CH
4. CH₂

The numbers 234,000 and 6.0012 can be represented in scientific notation as:

1. $2.34\times {10}^{-9} \mathrm{and} 6\times {10}^3$

2. 0.234 $\times {10}^{-6}$ and $60012\times {10}^{-9}$

3. $2.34\times {10}^{-9} \mathrm{and}$ $6.0012\times {10}^{-9}$

4. 2.34$\times {10}^5$ and 6.0012$\times {10}^0$

Which of the following solutions have the same concentration? 

1. (a), (b)

2. (b), (c)

3. (c), (d)

4. (b), (d)

Sulphuric acid reacts with sodium hydroxide as follows

${\mathrm{H}}_2{\mathrm{SO}}_4+2\mathrm{NaOH}\to {\mathrm{Na}}_2{\mathrm{SO}}_4+2{\mathrm{H}}_2\mathrm{O}$

When 1L of 0.1 M sulphuric acid solution is allowed to react with 1 L of 0.1 M sodium hydroxide solution, the amount of sodium sulphate formed and its molarity in the solution obtained are respectively-

1. 0.1 M, 7.10 g

2. 7.10 g, 0.025 M

3. 0.025 M, 3.55 g

4. 3.55 g, 0.25 M