The number of atoms of Na in 8 g of its sample is $x\times {10}^{23}$.The value of x( rounded off to the nearest integer) is

[Given : $N_A=6.02\times {10}^{23}mo{l}^{-1}$
and Atomic mass of Na=23.0u]

Q. Complete combustion of $3g$ of ethane gives x $\times {10}^{22}$ molecules of water. The value of x is _____ [Round off to the Nearest Integer].
[Use: $N_A=6.023\times {10}^{23};$ Atomic masses in u : C : 12.0; O : 16.0 : H : 1.0 ]

Q. The number of chlorine atoms in 20 mL of chlorine gas at STP is $x\times {10}^{21}$. The value of x (Rounded off to the Nearest integer) is
.
[Assume chlorine is an ideal gas at STP,
$N_A=6.023\times {10}^{23}$]

Q. $Ga$ (atomic mass = $70u$) crystallizes in a hexagonal close packed structure. The total number of voids in $0.581\text{g}$ of $Ga$ is $\times {10}^{21}$. (Round off to the nearest integer). [Given: $N_A=6.023\times {10}^{23}]$

Q. The number of chlorine atoms in 20 mL of chlorine gas at STP is ${10}^{21}$. (Round off to the Nearest Integer).


$[AssumechlorineisanidealgasatSTPR=0.083Lbarmo{l}^{-1}{K}^{-1},N_A=6.023\times {10}^{23}]$

Q. Ga (atomic mass $70u$) crystallizes in a hexagonal close packed structure. The total number of voids in $0.581g$ of Ga is $\times {10}^{21}$ (Round off to the nearest integer). $[\text{Given}=N_A=6.023\times {10}^{23}]$
(JEE Main 2021)