Question

a chemical reaction for the reaction of sodium hydroxide (naoh) and hydrochloric acid (hcl) is shown. the masses of some of the reactants and products are given in grams.
naoh + hcl → nacl + h₂o
16 g 24 g 12 g ?
how many grams of water were produced in the reaction?
a 18 g
b 28 g
c 40 g
d 52 g

Explanation:

Step1: Apply law of conservation of mass

According to the law of conservation of mass, the total mass of reactants equals the total mass of products. The mass of reactants is $16\ g+24\ g = 40\ g$.

Step2: Calculate mass of water

Let the mass of water be $x$. We know that mass of reactants = mass of products. So, $40\ g=12\ g + x$. Solving for $x$, we get $x = 40\ g- 12\ g=28\ g$.

Answer:

B. 28 g