Question

Which example of mass has 1.2×1024 oxygen atoms?

1 mole of peroxide (H2O2)

1 mole of water (H2O)

2 moles of ammonia (NH3)

2 moles of hydrogen gas (H

Answer 1

1 mol of hydrogen peroxide (H₂O₂)

Step-by-step explanation:

Convert the number of oxygen atoms to moles

`\text{Moles of O atoms} = 1.2 * 10^(24)\text{ O atoms} * \frac{\text{1 mol O atoms}}{6.022 * 10^(23)\text{ O atoms }} = \text{2.0 mol O atoms}`

1 mol of H₂O₂ contains 2 mol of O atoms.

B is wrong. 1 mol of H₂O contains 1 mol of O atoms.

C and D are wrong. NH₃ and H₂ contain no O atoms.

Answer 2

Answer: The correct answer is 1 mole of peroxide
`(H_2O_2)`

Step-by-step explanation:

According to mole concept:

1 mole of a substance contains
`6.022* 10^(23)` number of atoms.

For the given options:

Option 1: 1 mole of hydrogen peroxide
`(H_2O_2)`

1 mole of hydrogen peroxide contains 2 moles of hydrogen atom and 2 moles of oxygen atoms.

This means that 1 mole of hydrogen peroxide contains
`(2* 6.022* 10^(23)=1.2* 10^(24))` number of oxygen atoms.

Option 2: 1 mole of water
`(H_2O)`

1 mole of water contains 2 moles of hydrogen atom and 1 moles of oxygen atoms.

This means that 1 mole of water contains
`(1* 6.022* 10^(23)=6.022* 10^(24))` number of oxygen atoms.

Option 3: 2 moles of ammonia
`(NH_3)`

1 mole of ammonia contains 1 moles of nitrogen atom and 3 moles of hydrogen atoms.

This compound do not contain any oxygen atom.

Option 4: 2 moles of hydrogen gas
`(H_2)`

1 mole of hydrogen gas contains 2 moles of hydrogen atoms.

This compound do not contain any oxygen atom.

Hence, the correct answer is 1 mole of peroxide
`(H_2O_2)`