The density of a 2 M aqueous solution of NaOH is 1.28 g/$c{m}^3$. The molality of the solution is: 
[molecular mass of NaOH = 40 $gmo{l}^{-1}$]

1.	1.20 m	2.	1.56 m
3.	1.67 m	4.	1.32 m

To produce 20 moles of ammonia via Haber's process, how many moles of hydrogen molecules are required?

The maximum number of atoms is present in which of the following -

1. 1 g of Mg_(s)  

2. 1 g of O_{2 (g)}

3. 1 g of Li_(s)    

4. 1 g of Ag_(s)   

One mole of carbon atom weighs 12 g, the number of atoms in it is equal to, (Mass of carbon – 12 is $1.9926\times {10}^{-23}$ $g$)

1. $1.2\times {10}^{23}$

2. $6.022\times {10}^{22}$

3. $12\times {10}^{22}$

4. $6.022\times {10}^{23}$

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] 

Match list-I with list-II: