Question

which one of the following reactions is an acid - base reaction? hno₃ + koh → kno₃ + h₂o; li + 2nh₃ → 2linh₂ + h₂; agno₃ + kcl → kcl + kno₃; ch₄ + o₂ → co₂ + 2h₂o. question 8 10 pts which acid and base reacted producing ca₃(po₄)₂? calcium phosphate and calcium hydroxide; calcium hydroxide and phosphoric acid; phosphorus trichloride and calcium hydride; calcium chloride and potassium chloride. question 9 10 pts which one of the following solutions is not an acid - base buffer? ch₃cooh - ch₃coona; hf - kf; hclo₂ - kclo₂; hno₃ - kno₃

Explanation:

Step1: Recall acid - base reaction definition

An acid - base reaction involves an acid and a base reacting to form a salt and water. In the reaction $HNO_3+KOH
ightarrow KNO_3 + H_2O$, $HNO_3$ is an acid and $KOH$ is a base, and they form salt $KNO_3$ and water.

Step2: Analyze other reactions

• In $Li + 2NH_3

ightarrow2LiNH_2+H_2$, it is a redox reaction.

• In $AgNO_3+KCl

ightarrow KCl + KNO_3$, it is a double - displacement reaction.

• In $CH_4+O_2

ightarrow CO_2 + 2H_2O$, it is a combustion reaction.

Step3: Recall acid - base reaction for $Ca_3(PO_4)_2$

Calcium hydroxide $Ca(OH)_2$ (a base) and phosphoric acid $H_3PO_4$ (an acid) react to form calcium phosphate $Ca_3(PO_4)_2$.

Step4: Recall buffer definition

An acid - base buffer consists of a weak acid and its conjugate base or a weak base and its conjugate acid. $HNO_3$ is a strong acid, and $KNO_3$ is its salt. A buffer cannot be made from a strong acid and its salt.

Answer:

Question 7: $HNO_3+KOH
ightarrow KNO_3 + H_2O$
Question 8: calcium hydroxide and phosphoric acid
Question 9: $HNO_3 - KNO_3$