Question

Ca + HCl --> Na + HCl --> Mg + HCl --> K + H2O --> Ba + ... --> H2 ^ + Ba (OH)2

Answer 1

2Na + 2HCl = 2NaCl + H2
Ca + 2HCl= CaCl2 + H2
Mg + 2 HCl = MgCl2 + H2
2K + 2H2O = 2KOH + H2
Ba + 2H2O = Ba (OH) 2 + H2

Answer 2

The chemical reactions you've provided seem to be a mix of different reactions and elements, and they are not balanced or follow the rules of chemical reactions. Let's clarify and balance them:

1. Ca + HCl (hydrochloric acid) -> CaCl2 + H2 This is a typical reaction where calcium (Ca) reacts with hydrochloric acid (HCl) to produce calcium chloride (CaCl2) and hydrogen gas (H2).

2. Na + HCl (hydrochloric acid) -> NaCl + H2 Similar to the previous reaction, sodium (Na) reacts with hydrochloric acid (HCl) to produce sodium chloride (NaCl) and hydrogen gas (H2).

3. Mg + HCl (hydrochloric acid) -> MgCl2 + H2 Magnesium (Mg) reacts with hydrochloric acid (HCl) to produce magnesium chloride (MgCl2) and hydrogen gas (H2).

4. K + H2O (water) -> KOH + H2 Potassium (K) reacts with water (H2O) to produce potassium hydroxide (KOH) and hydrogen gas (H2).

5. Ba + H2O (water) -> Ba(OH)2 + H2 Barium (Ba) reacts with water (H2O) to produce barium hydroxide (Ba(OH)2) and hydrogen gas (H2).

So, in each of these reactions, a metal reacts with either hydrochloric acid or water to produce metal salts and hydrogen gas. The last reaction involving barium and water results in the formation of barium hydroxide.