If you mean 4 moles per litre then:
In 1 litre there is 4 moles, therefore in .25 litres there is 1 mole.
1 mole of Magnesium Chloride would produce 2 moles of chloride ions (MgCl2 can also be written as Mg1Cl2, which dissolves to produce 1Mg(2+) and 2Cl(1-) ions: a 1:2 ratio)
So the answer is 2 moles of Chloride ions.
Atoms are considered the smallest particles of an element because they are the basic unit. They cannot be broken down into any smaller substance.
12
Neon is the 10th element and has 10 protons. The mass of an element is the sum of the protons and neutrons.
22-10=12
Insulation wraps because independent is the variable you are changing to affect the dependent variable (what you are measuring)