Answer:
17)A. Solids
18) A. Frequently collide with each other and with surface of ballon
19) D. Particles are smaller at lower pressure.
The variable is what changes during an experiment. Hopefully this helped! :)
<u>Answer:</u> The correct answer is Option 1.
<u>Explanation:</u>
Neutralization reaction is defined as the reaction in which acid reacts with a base to produce a salt along with water.
Here, HCl is an acid and
is a base. When these two compounds react, the salt obtained is calcium chloride.
The equation for the above reaction is given by:

Hence, the correct answer is Option 1.