What is a chemical change?

A.) Splitting water into hydrogen and oxygen

B.) Breaking a block of solid ice into smaller pieces

C.) Freezing liquid water

D.) Boiling water

Consider the elements bromine and chlorine; which elements has a larger ionic radius ?

In the reaction between a crushed antacid tablet and vinegar what gas is emitted

3. how much energy in joules is required to evaporate .0005 kg of liquid ammonia to vapor at the same temperature? 4. how much energy ( in megajoules ) is given up by .75 kg of water at 0c when it freezes to form ice at 0c? 5. explain how heat works between and at critical temperatures?