Answer:
B3H5
Explanation:
The law of conservation of mass states that matter in an closed system is neither created nor destroyed by physical transformations or chemical reactions but changes from one form to the other.
That is, the sum of masses of the reactants = The sum of masses of the product
10.00g of Boron + x grams of Hydrogen = 11.55g of the product
Mass of hydrogen = 11.55 - 10.00 = 1.55g
Molar mass of Boron = 10.811g
Molar mass of Hydrogen = 1.00784g
Number of moles of Boron = (mass of Boron)/(molar mass of Boron) = 10/10.811 = 0.9249 mols
Number of moles of Hydrogen = (mass of Hydrogen)/(molar mass of Hydrogen) = 1.55/1.00784 =1.5379mols
0.9249 mols of Boron combines with 1.5379mols of Hydrogen
Dividing both sides mols by 0.9249 gives
1 mole of Boron combines with 1.66266 mols of Hydrogen
Converting 1.66266 to fractions we have 1.66266 approximately 5/3
or 1 mole of Boron combines with 5/3 moles of Hydrogen
Multiplying both sides by 3 we have
3 moles of Boron combines with 5 moles of Hydrogen
Molecular formula of the compound is
B3H5
