Answer:

Explanation:
1. Molecules of P₄
The molecular formula of phosphorus is P₄.

2. Atoms of P
One molecule of phosphorus contains four P atoms.

Answer:
Explanation:
Adding any solute to water will increase the boiling temperature, as it reduces the vapour pressure, meaning a slightly higher temperature is required in order for the vapour pressure to become equal to atmospheric pressure and boil the water. Essentially, adding any non-volatile solute (such as salt, baking soda or sugar) to a liquid causes a decrease in the liquid's vapour pressure.
_Mg + _HCL = _MgCl2 + H2
Separate the terms on each side:
_Mg + _HCl = _MgCl2 + H2
Mg- 1 Mg-1
H-1 H-2
Cl-1 Cl-2
Mg is balanced on both sides so move on to the next (put a 1 in the space).
1Mg
There are two H's and two Cl's on the results side, so to balance the equation put a 2 as a coefficient for HCl and it'll all balance out.
2HCl
Balamced equation will be:
1Mg + 2HCL = 1MgCl2 + H2