List three natural carbonates and give examples of soluble and insoluble ones. Write the reaction equation for CO2 gas and baryta water over 5 mins.

$$\text{BaCO}_3(\text{s}) + \text{CO}_2(\text{g}) + \text{H}_2\text{O}(\text{l}) \rightarrow \text{Ba(HCO}_3)_2(\text{aq})$$

2. Distinguish between $\text{Na}_2\text{CO}_3$ and $\text{KHCO}_3$ using the available reagents.

Here are three simple tests:

• Test 1: Using Phenolphthalein indicator

  • Procedure: Add a few drops of phenolphthalein indicator to separate solutions of $\text{Na}_2\text{CO}_3$ and $\text{KHCO}_3$.
  • Observation: The $\text{Na}_2\text{CO}_3$ solution will turn pink/red (strongly alkaline), while the $\text{KHCO}_3$ solution will show a faint pink color or remain colorless (less alkaline).
  • Explanation: Sodium carbonate is a salt of a strong base and a weak acid, leading to significant hydrolysis and a higher pH. Potassium hydrogen carbonate is less alkaline.

• Test 2: Using Magnesium Sulfate ($\text{MgSO}_4$) solution

  • Procedure: Add magnesium sulfate solution to separate solutions of $\text{Na}_2\text{CO}_3$ and $\text{KHCO}_3$ at room temperature.
  • Observation: With $\text{Na}_2\text{CO}_3$, an immediate white precipitate of magnesium carbonate forms. With $\text{KHCO}_3$, no precipitate forms in the cold solution. A precipitate would only form upon heating the $\text{KHCO}_3$ mixture.
  • Equations: $$\text{Na}_2\text{CO}_3(\text{aq}) + \text{MgSO}_4(\text{aq}) \rightarrow \text{MgCO}_3(\text{s}) + \text{Na}_2\text{SO}_4(\text{aq})$$ $$2\text{KHCO}_3(\text{aq}) + \text{MgSO}_4(\text{aq}) \rightarrow \text{Mg(HCO}_3)_2(\text{aq}) + \text{K}_2\text{SO}_4(\text{aq})$$ (Magnesium bicarbonate is soluble)

• Test 3: Using Barium Chloride ($\text{BaCl}_2$) solution

  • Procedure: Add barium chloride solution to separate solutions of $\text{Na