Answer:
First one: group
Second one: period
Third one: number of valence electrons
Last one: increases
Answer:
0.60 moles of Na₂SO₄
Explanation:
Molarity is an unit of concentration defined as the ratio between moles of solute and liters of solution.
A solution of Na₂SO₄ 0.40M contains 0.40 moles of solute (Na₂SO₄) per liter of solution.
As you have 1.5L of solution, moles of Na₂SO₄:
1.5L × (0.40mol / L) = <em>0.60 moles of Na₂SO₄</em>
Answer:
56.28 g
Explanation:
First change the grams of oxygen to moles.
(50.00 g)/(32.00 g/mol) = 1.5625 mol O₂
You have to use stoichiometry for the next part. Looking at the equation, you can see that for every 2 moles of H₂O, 1 mole of O₂ is produced. Convert from moles of O₂ to moles of H₂O using this relation.
(1.5625 mol O₂) × (2 mol H₂O/1 mol O₂) = 3.125 mol H₂O
Now convert moles of H₂O to grams.
(3.125 mol) × (18.01 g/mol) = 56.28125 g
Convert to significant figures.
56.28125 ≈ 56.28
