Chemical Formula of Sodium Sulfate is Na₂SO₄.
As we know, 1 mole of any substance contains 6.022 × 10²³ particles. So, 1 mole of Na₂SO₄ also contains 6.022 × 10²³ formula units of Na₂SO₄.
Also,
1 mole of Na₂SO₄ contains = 6.022 × 10²³ Atoms of S
So,
4.5 moles of Na₂SO₄ will contain = X atoms of S
Solving for X,
X = (4.5 moles × 6.022 × 10²³ Atoms) ÷ 1 mole
X = 2.70 × 10²⁴ Atoms of S
Result:
4.5 Moles of Na₂SO₄ contains 2.70 × 10²⁴ Atoms of Sulfur.
Answer:
Percentage mass of copper in the sample = 32%
Explanation:
Equation of the reaction producing Cu(NO₃) is given below:
Cu(s)+ 4HNO₃(aq) ---> Cu(NO₃)(aq) + 2NO₂(g) + 2H₂O(l)
From the equation of reaction, 1 mole of Cu(NO₃) is produced from 1 mole of copper. Therefore, 0.010 moles of Cu(NO₃) will be produced from 0.010 mole of copper.
Molar mass of copper = 64 g/mol
mass of copper = number of moles * molar mass
mass of copper = 0.01 mol * 64 g/mol = 0.64 g
Percentage by mass of copper in the 2.00 g sample = (0.64/2.00) * 100%
Percentage mass of copper in the sample = 32%
