What is the molar absorptivity of benzoic acid at 228 nm? (assume path length=1cm) The solution...

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What is the molar absorptivity of benzoic acid at 228 nm? (assume path length=1cm) The solution contains .010M HCl. Benzoic acid is 8.74mg/L

science chemistry

Answer 1

Answer #1

given the concentration of benzoic acid = 8.74 mg/L = 8.74 x 10^-3 g/L

Molecular mass of benzoic acid = 122.1 g/mol

Hence molar concentration of benzoic acid = (8.74 x 10^-3 g /122.1 g/mol) /L = 7.16 x 10^-5 M

According to Beer - Lambart law, the absorbance, A can be calculated as

A = ExCxL

where E = molar absorptivity,

C = concentration in mol/L = 7.16 x 10^-5 M

L = path length in cm = 1 cm

A = absorbance

=> molar absorptivity, E = A / CL

by putting the value of absorbance, A, C and L we can calculate the value of E.

Answer 2

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