Respuesta :

Molar mass Ra(OH)2 = 260 g/mol 
Moles = 987 g / 260 = 3.80 moles

Answer:

3.84mol

Explanation:

How many moles are in 987 grams of Ra(OH)2

the elements in the compound are as follows

radium

oxygen

and hydrogen

to get the the mole, we say the ratio of mass of the compound to the molecular mass(g/mol)

molecular mass= 223 + 16 * 2 + 1 * 2 =257 g/mol

mass=987g is defined as the quantity of matter in a body

mol=987/257

mol=3.84mol

mol has to do with the amount of a substance.