2. Using Tables 5 and 6 below, balance the following chemical reaction: Na2CO3 (aq)+CaCl2 (aq) → CaCO3 (s)+NaCl (aq)

Na₂CO₃  +  CaCl₂  →  CaCO₃  +  2 NaCl

Explanation:

Na₂CO₃  +  CaCl₂  →  CaCO₃  +  NaCl

First, determine what is balanced.  

Ca and CO₃ is balanced; there is one on each side.  

Na and Cl aren't balanced.  On one side, there is two of each, while on the other there is only one.  To fix this add a 2 in front of NaCl.  This will cause the equation to be balanced.

Na₂CO₃  +  CaCl₂  →  CaCO₃  +  2 NaCl

answer

i think the answer is a) as air pressure in an area increases, the density of the gas particles in that area decreases.

hope it