Answer:
1) 3.0 moles.
2) 2.0 moles.
3) 2.0 moles of H atoms.
4) 4. 6.02 x 10²³.
Explanation:
Q1: How many moles of chlorine are present in 3 moles of MgCI₂?
- MgCl₂ is dissociated according to the equation:
MgCl₂ → Mg + Cl₂.
Every 1.0 mole of Mg is dissociated to 1.0 mol of Mg and 1.0 mol of Cl₂.
∵ 1.0 mol of MgCl₂ gives 1.0 mol of Cl₂.
∴ 3.0 mol of MgCl₂ gives 3.0 mol of Cl₂.
Q2: How many moles of H₂0 are needed to produce 1 mole of O₂ in the following equation? 2H₂O → 2H₂ + O₂.
- From the balnced equation:
2H₂O → 2H₂ + O₂.
2.0 moles of H₂O produce 2.0 moles of H₂ and 1.0 mole of O₂.
∴ We need 2.0 moles of H₂O to produce 1.0 mole of O₂.
Q3: How many moles of hydrogen atoms are present in 1 mole of H2 gas?
- H₂ is dissociated according to:
H₂ → 2H.
1.0 mol of H₂ is dissociated to produce 2 atoms of H.
∴ 1.0 mol of H₂ contains 2.0 moles of H atoms.
Q4: How many atoms or molecules are in a mole?
- It is known that every mole of any compound contains Avogadro's number of atoms or molecules (6.022 x 10²³).
So, the answer is: 4. 6.02 x 10²³.
