Write balanced chemical reactions for each step in the two-step synthesis of calcium chloride. next, write an overall reaction for the two-step synthesis of aqueous calcium chloride from calcium and hydrochloric acid. you can do this by subtracting one equation from the other. your equations should include the details about state (s), (aq), (g), (l).

For the first reaction: Ca (s) + Cl2 (g) ⇒ CaCl2

For second reaction: Ca (s) + 2HCl (aq) ⇒ CaCl2 (aq) + H2 (g)

Explanation:

1) First you have to write the equations that describes the synthesis of calcium chloride from calcium (Ca) and chlorine (Cl2). The overall reaction can be separated in two semi-reactions, the oxidation of calcium and the reduction of chlorine.

Ca (s) ⇒ Ca+2  + 2e- (oxidation)

Cl2 (g) + 2 e- ⇒ 2Cl-   (reduction)

Ca (s) + Cl2 (g) + 2e- ⇒ CaCl2 (s) + 2e- (overall reaction)

Summarizing Ca (s) + Cl2 (g) ⇒ CaCl2

2) In the second part you must consider the reaction of Calcium and hydrochloric acid to form aqueous calcium chloride.

Ca (s) ⇒ Ca+2 + 2e-

2HCl (aq) ⇒ 2H+ (aq)  + 2Cl- (aq)

Ca (s) + 2HCl (aq) ⇒ CaCl2 (aq) + H2 (g)

the potential energy of the reactants is 200j.

from the energy diagram, the energy of the product formed is 350j; this means that, this reaction is an endothermic reaction, because it absorbs energy from its environment.

c is having 4 valence electrons and is bonded to three hydrogens and one sulphur atom, therefore, the number of bond pair is equal to four. as all the valence electrons are used in forming the bonds so, there is no lone pair left on carbon.

s is having 6 valence electrons and is bonded to one other sulfur atom and one carbon atom, therefore, the number of bond pair is equal to 2. as only two valence electrons are used in forming the bonds so, four electrons are left. therefore, two lone pairs are present on s.