Question

question 7
2 pts
h₂co₃ --> h₂o + co₂
decomposition reaction
combustion reaction
double replacement reaction
single replacement reaction
synthesis reaction
question 8
2 pts
ca + 2 hcl --> cacl₂ + h₂
single replacement reaction
combustion reaction
decomposition reaction
double replacement reaction
synthesis reaction
question 9
2 pts
2 agno₃ + ni --> ni(no₃)₂ + 2 ag
single replacement reaction
combustion reaction
decomposition reaction
double replacement reaction
synthesis reaction

Explanation:

Question 7

A decomposition reaction is when a single compound breaks down into two or more simpler substances. Here, $\ce{H2CO3}$ breaks into $\ce{H2O}$ and $\ce{CO2}$, so it's a decomposition reaction.

A single replacement reaction is when one element replaces another in a compound. In $\ce{Ca + 2HCl -> CaCl2 + H2}$, $\ce{Ca}$ replaces $\ce{H}$ in $\ce{HCl}$, so it's a single replacement reaction.

A single replacement reaction involves one element replacing another in a compound. In $\ce{2AgNO3 + Ni -> Ni(NO3)2 + 2Ag}$, $\ce{Ni}$ replaces $\ce{Ag}$ in $\ce{AgNO3}$, so it's a single replacement reaction.

Answer:

A. Decomposition reaction

Question 8