Question

How many grams of sodium are in 0.820 moles of na2so4?

Answer 1

Step-by-step explanation:

Number of moles are defined as given mass divided by molar mass of the compound or substance.

Mathematically, Number of moles =
`(mass given)/(molar mass)`

Since, it is given that number of moles is 0.820 and molar mass of
`Na_(2)SO_(4)` is 142 g/mol.

Therefore, calculate the mass as follows.

Number of moles =
`(mass given)/(molar mass)`

0.820 moles =
`(mass given)/(142 g/mol)`

mass given = 116.44 g

Thus, we can conclude that there are 116.44 grams of sodium in 0.820 moles of
`Na_(2)SO_(4)`.

Answer 2

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 Na₂SO₄ is - 142 g/mol.
1 mol of Na₂SO₄ has a mass of 142 g.
In 1 mol of Na₂SO₄ the mass of Na is 23 g/mol x 2 = 46 g.

Mass of Na in 1 mol of 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