Question

How many barium ions does one mole of barium phosphate contain?

Answer 1

Answer : The number of barium ion is,
`18.066* 10^(23)`

Explanation :

The formula of barium phosphate is,
`Ba_3(PO_4)_2`

Barium phosphate is formed from three barium ion and 2 phosphate ion by criss-cross method. That means,

1 mole of barium phosphate dissociates to give 3 moles of barium ion and 2 moles of phosphate ion.

Or,

As we know that, 1 mole contains
`6.022* 10^(23)` number of ions.

1 mole of barium phosphate dissociates to give
`3* 6.022* 10^(23)` moles of barium ion and
`2* 6.022* 10^(23)` moles of phosphate ion.

The number of barium ion =
`3* 6.022* 10^(23)=18.066* 10^(23)`

The number of phosphate ion =
`2* 6.022* 10^(23)=12.044* 10^(23)`

Hence, the number of barium ion is,
`18.066* 10^(23)`

Answer 2

The molecular formula of barium phosphate is Ba3(PO4)2. This is because, barium (Ba) is has +2 charge and the phosphate group (PO4) has a -3 charge.

Therefore, 1 mole of Ba3(PO4)2 has 3 moles of Ba2+ and 2 moles of PO4(3-)

Now:

1 mole of Ba2+ has
`6.023*10^(23)`Ba2+ ions

Therefore, 3 moles of Ba2+ would correspond to : 3*6.023*
`10^(23) = 1.807*10^(24)` Ba2+ ions