A student attempted to identify an unknown compound by the method described in this experiment. When he heated a sample weighing 1.031 g the mass went down to 0.688 g. When the product was converted to a chloride the mass went up to 0.748 g.

1. Explain if you believe the sample to be a carbonate or hydrogen carbonate. (I said it is a hydrogen carbonate due to the loss of mass)

2. Write the two possible chemical equations for the reaction that you believe occurred; one for sodium and one for potassium (carbonate or hydrogen carbonate). (we are supposed to use these two formulas but I am not sure how: 2XHCO ₃ → X ₂ CO ₃ + H ₂ O + CO ₂ this is hydrogen carbonate X ₂ CO ₃ + 2 H+ + 2 Cl-→ 2 XCl + H ₂ O + CO ₂ This one is for the hydrochloric acid being added)

3. Show by calculation how many moles of the chloride salt would be produced from one mole of the original compound; one for sodium and one for potassium (carbonate or hydrogen carbonate).
4. Fill out the following information to help you determine how many grams of the chloride salt would be produced from one molar mass of the original compound?

If NaHCO ₃ ____________ g original compound → ____________ g chloride

If KHCO ₃ ____________ g original compound → ____________ g chloride

If Na2CO ₃ ____________ g original compound → ____________ g chloride

If K ₂ CO ₃ ____________ g original compound → ____________ g chloride