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2 years ago

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The dipole moment (μ) of HBr (a polar covalent molecule) is 0.851D (debye), and its percent ionic character is 12.6 % . Estimate

the bond length of the H−Br bond in picometers. Note that 1 D=3.34×10−30 C⋅m and

1 answer:

Sati [7]2 years ago

8 0

Answer:

Bond length of HBr = 141 pm

Explanation:

$\% \ ionic\ character=\frac{measured\ dipole\ moment}{dipole\ moment\ of\ 100\% ionic\ compound(\mu_(ionic))} \times 100 \%$

measured dipole moment of HBr = 0.851 D

$1D=3.34\times 10_^{-30}C.m$

therefore,

dipole moment of HBr in C.m is,

$0.851D\times (\frac{3.34\times 10^{-30}C.m}{1D} )=2.84 \times 10^{-30} C.m$

dipole moment is related with charge and bond length as follows:

$\mu_{ionic}=Q\times r$

Here Q is charge and r is interatomic distance or bond length

In case of HBr, Q is 1.6×10^-19 C.

Calculate diople moment HBr, $\mu_(ionic)$ as follows:

$12.6=\frac{2.84\times 10^{-30}C.m}{\mu_{ionic}}\times 100 \\\mu_{ionic}=\frac{2.84\times 10^{-30}C.m}{12.6}\times 100\\\mu_{ionic}=Q\times r\\2.25 \times 10^{-29}C.m=1.6 \times 10^{-19}C \times r\\r=1.41\times 10^{-10}m\\=141pm$

Bond length of HBr is 141 pm

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Here's what I get

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mihalych1998 [28]

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2 years ago