1A. Give the formula of each product when calcium carbonate (CaCo3) is heated
___ and _

B. The relative formula mass (Mr) of a Group 2 metal carbonate is 197
Relative atomic mass (Ar): C=12 O=16
Calculate the relative atomic mass (Ar) of the Group 2 metal in the metal carbonate.
Name the Group 2 metal.

1A When Calcium carbonate (CaCO3) is heated (this means when there is added O2). When it's strongly heated, calcium carbonate will undergo a thermal decomposition to form calcium oxide (CaO) and carbon dioxide (CO2).

2 CaCO3 + O2 → 2CaO + 3CO2

CaO and CO2 are the products formed

B) A metal carbonate has a Molecular mass of 197 g/mole

The metal carbonate has a structural formula of Mn(CO3)x

The metal is a group 2 metal, this means it has 2 valence electrons. The oxidation number is 2

Carbonate (CO3) has an oxidation number of -2

This means the ratio metal/carbonate = 1:1

The molecular mass of carbonate = 1*12 + 3*16 = 60 g/mole

The molecular mass of the metal = 197 - 60 = 137 g/mole

The metal with molecular mass 137 g/mole is Barium.

Barium is a group 2 metal.

The metalcarbonate is BaCO3