<span>the molar mass of a compound is the sum of the products of the atomic masses by the number of atoms of the element.
molar mass of Na</span>₂SO₄<span> is - 142 g/mol.
1 mol of </span>Na₂SO₄<span> has a mass of 142 g.
In 1 mol of </span>Na₂SO₄<span> the mass of Na is 23 g/mol x 2 = 46 g.
Mass of Na in 1 mol of </span>Na₂SO₄ is - 46 g
mass of Na in 0.820 mol of Na₂SO₄ - 46 g /1 mol x 0.820 mol = 37.72 g.
mass of Na is 37.72 g
Answer:
Explanation has been given below.
Explanation:
Let's consider solubility equilibrium of an ionic insoluble compound e.g. 
Equilibrium constant of this solubility equilibrium is represented in terms of solubility product (
) which is expressed as-
![K_{sp}=[Ba^{2+}][SO_{4}^{2-}]](https://tex.z-dn.net/?f=K_%7Bsp%7D%3D%5BBa%5E%7B2%2B%7D%5D%5BSO_%7B4%7D%5E%7B2-%7D%5D)
Now, if we add an ionic salt e.g. 
with a common ion 
then concentration of increases.
But, at a constant temperature, is constant.
Therefore, to keep constant, excess amount of will combine with free 
ion in solution and produce .
Hence, as a whole, solubility of decreases.
Yes this is know as the c value. It is usually used in q=mc change in temperature
Answer:
<h2><em><u>b. The production of a Hydrocarbon</u></em></h2>
Explanation:
In Combustion reaction usually occurs when a hydrocarbon reacts with oxygen to produce carbon dioxide and water.
When we say STP that means the system is at its standard temperature and pressure. Both systems is having the same condition hence temperature and pressure is constant. We then set the amount of gas in both cases to be equal. Hence from the ideal gas law,
PV=nRT we can say that with everything constant, volume must also be constant.
The answer is (2) 2 L of methane gas.
