Answer: The space occupied by the gas at 400 torr and
is 250 mL.
Explanation:
Given:
= 250 mL,
= 800 torr, 
,
= 400 torr, 
Formula used is as follows.

Substitute the values into above formula as follows.

Thus, we can conclude that space occupied by the gas at 400 torr and
is 250 mL.
The answer is D. Effective collisions lead to chemical reactions!
Answer:
The answer to your question is Covalent
Explanation:
Both, Hydrogen and Chlorine are non metals, when two nonmetals attach the share electrons and the type of bonding formed is polar covalent because they have different sizes, hydrogen is smaller than chlorine.