Magnesium carbonate decomposes on heating to form magnesium oxide and carbon dioxide as shown. MgCO3 -> MgO + CO2

How much magnesium carbonate is needed to make 10.0g of magnesium oxide?

A. 3.5g
B. 10.5g
C. 21.0g
D. 6.5g

please answer, I have a test right now​

you need to take a look at the periodic system in order to sort these elements into pairs that would most likely exhibit similar chemical properties. first, you need to find elements that are found in the same group (groups are vertical in the periodic system), and then to see whether they have the same valence number. if they meet these criteria, they will have similar properties.

the first pair: ne (neon) and kr (krypton), are noble gases found in group 8

the second pair: li (lithium) and k (potassium), found in group 1

the third pair: s (sulfur) and te (tellurium), found in group 6

you didnt put any of the following