Question

calculate the mass of 2.5*10^23 units of calcium phosphate

Answer 1

Answer:

Formula units is used for salts made by ion namely cation and anion .

Formula units=moles×Na

Na=avagadro number which is 6.022×10²³

Moles=2.5×10²³/6.022×10²³=0.4151 moles

Mass=moles×molar mass

Mass=0.4151×310=128.6947gm

Answer=\pink{128.69gm}128.69gm

hope it helps.

Answer 2

Answer:

Formula unit mass of CaSO

4

.2H

2

O

= (Number Calcium atoms x atomic mass of Calcium) + (Number Sulphur atoms x atomic mass of sulphur) + (Number Oxygen atoms x atomic mass of Oxygen) + (Number Water molecules x Molecular mass of water molecule)

=(1×40)+(1×32)+(4×16)+(2×18)

=40+32+64+36

=172

Formula unit mass of gypsum = 172