MCQ
Which of the following is paramagnetic
- ✓$N{i^{ + 2 }}$
- B$C{u^ + }$
- C$Z{n^{ + 2 }}$
- D$S{c^{ + 3 }}$
$_{28}Ni = [Ar]\;3{d^8}4s_2^{}$ ; $N{i^{2 + }} = [Ar]\;3{d^8}4{s^0}$
Because $N{i^{2 + }}$ have $2$ unpaired electrons in $3d$ subshell therefore it is paramagnetic.
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| $A/mol\,L^{-1}$ | $0.2$ | $0.2$ | $0.4$ |
| $B/mol\,L^{-1}$ | $0.3$ | $0.1$ | $0.05$ |
| $r_0/mol^{-1}s^{-1}$ | $5.0\times 10^{-5}$ | $5.0\times 10^{-5}$ | $1.4\times 10^{-4}$ |

$(I)$ $1\,mol$ of $A$ and $2\,mol$ of $B$ in a $1\,L$ vessel
$(II)$ $2\,mol$ of $A$ and $2\,mol$ of $B$ in a $2\,L$ vessel
$(III)$ $0.2\,mol\, A$ and $0.2\,mol\,B$ in $0.1\,L$ vessel
Which reactant sample reacts by highest rate if reactant is in gaseous state and do not follow zero order reaction ?