Question

1. how many moles of oxygen atoms are present in 5.00 mol of diphosphorus pentoxide? (0.5 points) 15.0 mol 18.2 mol 12.5 mol 25.0 mol 6. calculate the number of moles of hydrogen atoms in 11.5 mol of water. (0.5 points) 3.70 mol 23.0 mol 8.90 mol 28.9 mol

Explanation:

Question 5

Step1: Identify formula of diphosphorus pentoxide

Diphosphorus pentoxide has the formula \( P_2O_5 \), meaning 1 mole of \( P_2O_5 \) contains 5 moles of O atoms.

Step2: Calculate moles of O atoms

Given 5.00 mol of \( P_2O_5 \), moles of O = \( 5.00 \, \text{mol} \times 5 = 25.0 \, \text{mol} \)? Wait, no—wait, \( P_2O_5 \): 2 P, 5 O. So 1 mol \( P_2O_5 \) → 5 mol O. So 5.00 mol \( P_2O_5 \) × 5 mol O / 1 mol \( P_2O_5 \) = 25.0? Wait, but the options have 25.0 as an option. Wait, maybe I miscalculated? Wait, no: \( P_2O_5 \) is \( P_2O_5 \), so each mole has 5 O atoms. So 5.00 mol × 5 = 25.0 mol. Wait, but the first option is 15.0, which is wrong. Wait, maybe I misread the formula. Wait, diphosphorus pentoxide: \( P_2O_5 \), yes. So 5 moles of O per mole of \( P_2O_5 \). So 5.00 mol × 5 = 25.0 mol. So the correct option is 25.0 mol? Wait, but let me check again. Wait, maybe the formula is \( P_2O_3 \)? No, pentoxide is 5. So \( P_2O_5 \). So 5.00 mol × 5 = 25.0 mol. So the answer is 25.0 mol.

Step1: Identify formula of water

Water has the formula \( H_2O \), meaning 1 mole of \( H_2O \) contains 2 moles of H atoms.

Step2: Calculate moles of H atoms

Given 11.5 mol of \( H_2O \), moles of H = \( 11.5 \, \text{mol} \times 2 = 23.0 \, \text{mol} \). Because each \( H_2O \) has 2 H atoms. So 11.5 mol × 2 mol H / 1 mol \( H_2O \) = 23.0 mol.

Answer:

25.0 mol (Option: 25.0 mol)

Question 6