Question

What is the concentration of chlorophyll a in spinach?

Equation for the standard curve is y=2613.101-0.049

mass of spinach is 0.1010 g

total volume of spinach extract is 25 ml

absorabance is 0.164

What is concentration of chlorophylla in extract

What is number of grams of chlorophylla in 25 ml spinach extract solution

What is concentration of chlorophylla in spinach (mg chlorophyll a/ gram spinach)

What is the true concentration of chlorophyll a in spinach?

Answer 1

We have to use the Beer's law to calculate the concentration of chlorophyll A in spinach, i.e., .

The standard curve equation given is which is equavalent to y = mx + c, where y is absorbance and x is concentration of the sample.

At the given absorbance, A = 0.164, concentration can be calculated.

  

     

  

So, the concentration of chlorophyll A in spinach is 8.1 X10 ^-5mol/L.

Mol.wt. of chlorophyll is 893.51g/mol.

1 mol is having 893.51 g

8.1 X 10^-5 mol will have 893.51 X8.1 X10^-5 g = 7.23 X 10^-2 g =0.072 g

= 72.3 mg

We can calculate the concentration of chlorophyll A in 25 mL of extract by the formula

  

The concentration of chlorophyll A in spinach will be equal to (72.3/0.1010 )mg/g = 715.84 mg/g