How many grams of beryllium are in 147g of the mineral beryl (be3al2si6o18?//?

The grams of beryllium that are in 147 g of the mineral is calculated as follows

find the moles of the mineral

that is = mass/molar mass (537g/mol)

= 147g/537g/mol = 0.274 moles

mass of Be = moles x molar mass of Be x 3 since there is 3 Be atom in the mineral

= 0.274 mol x3 x 9 g/mol = 7.4 g