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Oxy-myoglobin was measured at wavelength of 417 nm with molar absorptivity of 12,800 M^-1cm^-1. Met-myoglobin was...

Oxy-myoglobin was measured at wavelength of 417 nm with molar absorptivity of 12,800 M^-1cm^-1. Met-myoglobin was measured at wavelength of 409 nm with molar absorptivity of 17,900 M^-1cm^-1. In 10.0 g of meat (3.0 mL of total solution) the absorbance of oxy-myoglobin was 0.769 using a 1 cm cell and the met-myoglobin was 0.346. Find the moles of oxy-myoglobin and the met-myoglobin per gram of meat.

Expert Solution

A = ECl

A = absorbance

E = molar absorptivity ,

C = concentration of material =

l = length of sample tube = 1 cm

Concentration of Oxy-myoglobin = A/El

= 0.769/(12,800*1)

= 6.008*10^-5 M

Concentration of met-myoglobin = 0.346(17900*1)

= 1.933*10^-5 M

No of moles of Oxy-myoglobin in 10 grams sample

= M* V = 6.008*10^(-5)*0.003 = 1.8024*10^-7 mole

no of moles in 1 gram meat = 1.8024*10^-7/10 = 1.8024*10^-8 mole

No of moles of met-myoglobin in 10 grams sample

= M* V = 1.933*10^(-5)*0.003 = 5.799*10^-8 mole

no of moles in 1 gram meat = 5.799*10^-8/10 = 5.799*10^-9 mole

queen_honey_blossom answered 1 year ago

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