Question

Identify the elements that undergo changes in oxidation number in the reactions:

•NaI(aq)+3HOCl(aq)→NaIO3(aq)+3HCl(aq)

___________
3SO2(g)+2HNO3(aq)+2H2O(l)→3H2SO4(aq)+
2NO(g)
________
•2H2SO4(aq)+2NaBr(s)→Br2(l)+SO2(g)+
Na2SO4(aq)+2H2O(l)

Answer 1

The first reaction is
•NaI(aq)+3HOCl(aq)→NaIO3(aq)+3HCl(aq)

The elements that undergo changes in oxidation number are Iodine and Chlorine

The second reaction is
3SO2(g)+2HNO3(aq)+2H2O(l)→3H2SO4(aq)+2NO(g)

The elements that undergo changes in oxidation number are Sulfur and Nitrogen

The third reaction is
•2H2SO4(aq)+2NaBr(s)→Br2(l)+SO2(g)+Na2SO4(aq)+2H2O(l)

The elements that undergo changes in oxidation number are Sulfur and Bromine

Answer 2

Explanation:

1) $NaI(aq)+3HOCl(aq)\rightarrow NaIO_3(aq)+3HCl(aq)$

The iodine elements is going under oxidation in the given reaction that is from -1 to +5.

NaI

1+x=0

x=-1

In NaI , the oxidation state of iodine is -1

1+x+(3)(-2)=0

x = +5

In $NaIO_3$ , the oxidation state of iodine is +5.

2) $3SO_2(g)+2HNO_3(aq)+2H_2O(l)\rightarrow 3H_2SO_4(aq)+2NO(g)$

The sulfur elements is going under oxidation in the given reaction ythat is from +4 to +6.

$SO_2$

x+(2)(-2)=0

x = +4

In$SO_2$ , the oxidation state of sulfur is +4.

$H_2SO_4$

2+x+(4)(-2)=0

x = +6

In $H_2SO_4$ , the oxidation state of sulfur is +6.

3)$2H_2SO_4(aq)+2NaBr(s)\rightarrow Br_2(l)+SO_2(g)+Na_2SO_4(aq)+2H_2O(l)$

The bromine elements is going under oxidation in the given reaction that is from -1 to 0.

NaBr

1+x=0

x=-1

in NaBr the oxidation state of bromine is -1.

$Br_2$

2(x)=0

x = 0

In $Br_2$ , the oxidation state of bromine is 0.