Gram formula mass

Gram formula mass

                                  The formula mass of an ionic compound expressed in grams is called Gram formula mass.

Reason

            The reason is an ionic compound does not exist in molecular form. That’s why the sum of the masses of individual ions makes up the formula mass.

 Number of gram formula of ionic species=mass of ionic substance/formula mass of an ionic

For example

1 gram formula (mole)  of NaCl = 58.5 of NaCl

                                                       6.02x10²³ formula unit of NaCl.

1 gram formula (mole)  of AgNO₃ = 170 of AgNO₃

                                                                                                                                                  6.02X10²³ Formula unit of AgNO₃