Answer:

Explanation:
Calcium is the element of the group 2 and period 4 which means that the valence electronic configuration is
.
Chlorine is the element of the group 17 and period 3 which means that the valence electronic configuration is
.
Thus, calcium losses 2 electrons to 2 atoms of chlorine and these 2 atoms of chlorine accepts each electron to form ionic bond. This is done in order that the octet of the atoms are complete and they become stable.
Ca Cl
2 1
Cross multiplying the valency, We get, 
Thus, the formula of calcium chloride is
.
Answer:
The answers to the questions are given below.
Explanation:
According to Le Chatelier's principle, if an external constrain such as change in concentration, temperature or pressure is imposed on a chemical system in equilibrium, the equilibrium will shift in order to neutralize the effect.
A. Effective of removing ammonia, NH3.
N2(g) + 3H2(g) ⇌ 2NH3(g)
Removing NH3 from the reaction simply means we are left with more reactants and no product. Therefore, the reactant will react to produce the product. Hence, the equilibrium position will shift to the right.
2. Effect of removing H2
N2(g) + 3H2(g) ⇌ 2NH3(g)
Remoing H2 simply means we have more products and less reactant. Therefore, the product will be convert to reactant. Hence, the equilibrium position will shift to the left.
C. Effect of adding a catalyst.
N2(g) + 3H2(g) ⇌ 2NH3(g)
Catalyst does not affect the equilibrium position. It only creates an alternative path to arrive at the product within a short time. Hence, it has no effect.
Answer:
THE SOUND TRAVELS FASTER IN SOLIDS BECAUSE ITS MOLECULES ARE CLOSE TO EACH OTHER WHILE LIQUIDS MOLECULES ARE NOT TIGHT AS OF SOLID AND IN GAS THE MOLECULES ARE FREE