How many grams of residue is obtained by heating 2.76 g of silver carbonate?

(Given : Molar mass of $\mathrm{C}, \mathrm{O}$ and Ag are 12, 16 and $108 \mathrm{~g} \mathrm{~mol}^{-1}$ respectively)

Arrange the following atomic orbitals of multi electron atoms in order of increasing energy.

A. $n=3, l=2, m=+1$

B. $n=4, l=0, m=0$

C. $n=6, l=1, m=0$

D. $n=5, l=1, m=+1$

E. $n=2, l=1, m=+1$

Choose the correct answer from the options given below:

Identify the correct statements from the following :

A. Heisenberg uncertainty principle is applicable to electrons.

B. The size of $2 p_x$ orbital is less than the size of $3 p_x$ orbital.

C. The energy of 2 s orbital of H atom is equal to the energy of 2 s orbital of Li .

D. The electronic configuration of Cr is $[\mathrm{Ar}] 3 \mathrm{~d}^5 4 \mathrm{~s}^1$

Choose the correct answer from the options given below:

What is the mole fraction of water in $10 \%$ by weight $(\mathrm{w} / \mathrm{w})$ of aqueous urea solution?

[Given: Molar mass of $\mathrm{H}, \mathrm{O}, \mathrm{C}$ and N are $1,16,12$ and $14 \mathrm{~g} \mathrm{~mol}^{-1}$ respectively.]