A pupil heated 1.24 g of copper carbonate strongly. The chemical reaction which took place is represented by the equation:

CuCO3(s) → CuO(s) + CO2(g)

He then heated the 0.80 g of solid again. When he weighed it after cooling, its
mass was still 0.80 g. Explain why it had not changed in mass this time.

After the solid which remained had cooled, he weighed it.

He found that its mass was 0.80 g.

(i) Why did the pupil find a decrease in mass in this experiment?

d: the voltage of the secondary coil is less than that of the primary coil.

im not suree sorry if wrong

each chemical family is represented as a group or column on the periodic table. based on chemical properties, there are 6 types of chemical families. group 1 represents alkali metals, group 2 represents alkaline earth metals, groups 3 to 12 represent transition metals, groups 13 to 16 represent non-metals and other metals, group 17 represents halogens and group 18 represents noble gases.