The oxidation number of phosphorus in Ba(H₂PO₂)₂ is:

1. +3

2. +2

3. +1

4. -1

The oxidation state of Cr in [Cr(NH₃)₄Cl₂]⁺ is:

1. +3

2. +2

3. +1

4. 0

A redox reaction among the following is

1. $CdC{l}_2+2KOH\to Cd{\left(OH\right)}_2+2KCl$

2. $BaC{l}_2+K_{2}S{O}_4\to BaS{O}_4+2KCl$

3. $CaC{O}_3\to CaO+C{O}_2$

4. $2Ca+O_2\to 2CaO$

The reducing ability of the metals K, Au, Zn, and Pb follows the order

Which of the following transformations can be carried out by using HI as a reducing agent, under acidic conditions? $[Given: I_2(s)\to 2I^{-} E°=0.54 V]$

(i) $C{u}^{+}\to Cu\left(s\right) E°=0.52 V$

(ii) $C{r}^{3+}\to C{r}^{2+} E°=-0.41$

(iii) $F{e}^{3+}\to F{e}^{2+} E°=0.77 V$

(iv) $F{e}^{2+}\to Fe\left(s\right) E°=-0.44 V$

1. (i) and (iii)

2. (ii) and (iv)

3. only (iii)

4. Only (ii)

A solution (5 mL) of an acid X is completely neutralised by y mL of 1 M NaOH. The same volume (y mL) of 1 M NaOH is required to neutralise 10 mL of 0.6 M of $H_{2}S{O}_4$ completely. The normality (N) of the acid X is

1. 1.2

2. 2.4

3. 4.8

4. 0.6

The reaction,

$K_{2}C{r}_2{O}_7+mFeS{O}_4+n{H}_{2}S{O}_4\to C{r}_2{\left(S{O}_4\right)}_3+pF{e}_2{\left(S{O}_4\right)}_3$
$+K_{2}S{O}_4+q{H}_{2}O$

when balanced,m, n, p and q are, respectively

1. 6, 14, 3, 14

2. 6, 7, 3, 7

3. 3, 7, 2, 7

4. 4, 14, 2, 14

When zinc rod is directly placed in copper sulphate solution:

1. The blue colour of the solution starts intensifying.

2. The solution remains electrically neutral.

3. The temperature of the solution falls.

4. The weight of the zinc rod starts increasing.

The species which is unable to show disproportionation reaction is

1. $Cl{O}_3^{-}$

2. $Cl{O}_4^{-}$

3. $Cl{O}_2^{-}$

4. $Cl{O}^{-}$

1.250 g of metal carbonate $\left(MC{O}_3\right)$ was treated with 500 mL of 0.1 M HCl solution. The unreacted HCl required 50.0 mL of 0.500 M NaOH solution for neutralization. Identify the metal M

1. Mg

2. Ca

3. Sr

4. Ba