Question

0.023 g of sodium metal is reacted with 100`cm^(3)` of water. The pH of the resulting solution is
A. 10
B. 11
C. 9
D. 12

Answer 1

Correct Answer - D
`Na+H_(2)O rarr NaOH +(1)/(2) H_(2)`
1 mol of Na produces 1 mole of NaOH
0.023 g Na`=(0.023)/(23)=10^(-3) ` mole
`:. ` NaOH produced `10^(-3)` mole
`:. |NaOH |=(10^(-3))/(100)xx 1000=10^(-2)M`
`pOH =2` or `pH =14-2 =12`