Question

The number of electrons in 1.8 ml of $H_{2}O$ will be:

• A. $0.1N_A$
• B. $0.2N_A$
• C. $0.3N_A$
• D. $N_A$

Answer 1

Answer: (D)

$N_A$

There is a total of 10 electrons in $H_{2}O$ molecule.

moles of $H_{2}O\left(n\right)=\frac{massofsubstance}{molarmass}$

Therefore, 1.8 ml of $H_{2}O$ means 0.1 mole

of $H_{2}O$

Number of atoms = $n\times$ Avogrdro Number

Number of atom = $0.1\times 6.022\times {10}^{23}$

$=0.6022\times {10}^{23}$

Number of electron of $H_{2}O$ = $0.6022\times {10}^{23}\times 10$

$=6.022\times {10}^{23}$ = Avogard's number

So, the correct option is $D$