Answer:
The completed reaction is
CaCO3 + 2 HCl → (Ca+2 + 2 Cl-)aq + H2O + CO2↑
4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48
Step-by-step explanation:
4*1 = 4
4*2 = 8
4*3 = 12
and so on...
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