Answer:
Reverse the
reaction
Explanation:
Reactions:

Overall:

As can be seen, in the overall reaction we have
in the reactants like in the second reaction and
in the products. The
is in the first reaction but as a reactant so we need to reverse that reaction:

Combining:


Answer:
V₁ = 10 mL
Explanation:
Given data:
Initial volume of HCl = ?
Initial molarity = 3.0 M
Final molarity = 0.10 M
Final volume = 300.0 mL
Solution:
Formula:
M₁V₁ = M₂V₂
M₁ = Initial molarity
V₁ = Initial volume of HCl
M₂ =Final molarity
V₂ = Final volume
Now we will put the values.
3.0 M ×V₁ = 0.10 M×300.0 mL
3.0 M ×V₁ = 30 M.mL
V₁ = 30 M.mL /3.0 M
V₁ = 10 mL
I think the answer is a, volume, but I still might be wrong.
1 mol of any particles = 6.02*10²³ particles
56 mol*6.02*10²³ molecules of water/1 mol =3.37*10²⁵