When 10g of calcium carbonate is heated,4.4g of carbon dioxide escape out. the amount of residue left is:

The dissociation of calcium carbonate, CaCO3, to simpler compounds can be expressed as,
                        CaCO3 --> CaO + CO2
The precipitate is CaO and its amount is calculated through the difference which will give us the answer of 5.6 g. 

Adozen is 12, and your needing to calculate the weight of one medium egg, so i would do 21/12=1.75 per egg, and check your answer by doing 1.75 * 12= 21 : ) : ): ): ): ) i hoped i