Many of the elements on the periodic table will always form ions that have the same charge. The alkali metals (shown in yellow) always form +1 ions. The alkaline earth metals (red) always form +2 ions. The halogens (blue) always form -1 ions.
Hiii,so the problem is ♀️
Given question is incomplete. The complete question is as follows.
Balance the following equation:

Answer: The balanced chemical equation is as follows.

Explanation:
When a chemical equation contains same number of atoms on both reactant and product side then this equation is known as balanced equation.
For example, 
Number of atoms on reactant side:
H = 5
P = 1
O = 6
Ca = 1
Number of atoms on product side:
H = 6
P = 2
O = 9
Ca = 1
In order to balance this equation, we will multiply
by 2 on reactant side and we will multiply
by 2 on product side. Hence, the balanced chemical equation is as follows.

Answer: Hydrogen and Helium
Explanation: Hydrogen is made from from one proton and one electron, making them one of the simplest forms of elements in the universe. Combining hydrogen atoms creates helium, the second most common element in the Universe.
Answer:
Filtration
Explanation:
Filtration would be best because the sand particles would be trapped in the filter paper and the water would go through so the mixture would be separated