Question

)The empirical formula of Boron Hydride is BH3. Calculate molecular formula when the measured mass of the compound is 27.66.

Answer 1

Hi,

Here is your answer

Given:

Emperical Formula of Boron Hydride=BH₃

Measured mass(molar mass of emperical formula)=27.66

To Find:

Molecular formula

Solution:

Molecular mass of BH₃=10.81+3=13.81(molar mass of molecular formula)

Molecular formula is given by the equation

Molecular formula=n×empirical formula-equation 1

n=molar mass of molecular formula/molar mass of emperical formula

n=27.66/13.81

n=2

Substitute the value of n in equation 1

We get,

Molecular formula=2(BH₃)

Molecular formula=B₂H₆

Notes:

1.Molecular formula=n×empirical formula

2.n=molar mass of molecular formula/molar mass of emperical formula

Hope this helps you.