Question

How much positive charge is in 1.4 kg of oxygen? The atomic weight (15.9994 g) of oxygen contains Avogadro’s number of atoms, with each atom having 8 protons and 8 electrons. The elemental charge is 1.602 × 10−19 C and Avogadro’s number is 6.02

Answer 1

`6.7511* 10^7\ C`

Step-by-step explanation:

The atomic weight of oxygen = 15.9994 g

This mass corresponds to 1 mole of the oxygen atoms.

Thus,

15.9994 g mass of oxygen contains
`6.02* 10^(23)` atoms of oxygen.

1.4 kg = 1400 g ( 1 kg = 1000 g)

So,

1400 g mass of oxygen contains
`\frac {6.02* 10^(23)}{15.9994}* 1400` atoms of oxygen.

Number of atoms in 1400 g of oxygen =
`526.769754* 10^(23)`

Also, 1 atom of oxygen contains 8 protons

Charge of 1 proton = +
`1.602* 10^(-19)\ C`

So, Charge on 1 atom of oxygen =
`8* 1.602* 10^(-19)\ C`

Thus,

Charge on
`526.769754* 10^(23)` atoms of oxygen =
`526.94476* 10^(23)* 8* 1.602* 10^(-19)\ C=6.7533* 10^7\ C`

Thus, positive charge in 1.4 kg of oxygen =
`6.7511* 10^7\ C`