Answers to the first series of questions-

1. Chemical reactions and changes

a. H2 S2 O7 (l) + H2 O(l) — — — — -> 2 H2 SO4 (l)

b. SO2 (g) + 2 H2 S(aq) — — — — -> 3 S(s) + 2 H2 O (l)

c. 2 Ag(s) + 2 HCl(aq) — — — → 2 AgCl + H2

d. 2 NaOH (aq) + H2 SO4 (aq) — — — → Na2 SO4 (aq) + 2 H2 O(l)

2. Life Processes in living organisms- 1