As a cake bakes, sodium bicarbonate reacts with acids in the cake. the bicarbonate ion and the anion in the acid change places to make carbonic acid. the carbonic acid then breaks down to produce carbon dioxide bubbles that make the cake rise. check all of the reactions that occurred.
check all reactions that occurred
combustion

decomposition

double replacement

synthesis

1) Answer is: double replacement.

Balanced chemical reaction: NaHCO₃ + HCl → NaCl + H₂CO₃.

Double replacement reactions (double displacement or metathesis reactions), two ionic compounds are exchanged, making two new compounds.

2) Answer is: decomposition.

Balanced chemical reaction: H₂CO₃ → H₂O + CO₂.

Decomposition is reaction where one substance is broken down into two or more simpler substances.

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

i think it's c. if you look search electronic symbol on google and then click on wiki it shows you a