Question

The data in the table are used to create a calibration curve for the determination of RNA from its absorbance at 260 nm. Use a spreadsheet and the least-squares method to determine the slope and y-intercept of the best straight line fit to the calibration curve. Do not subtract the blank reading when creating the calibration curve. RNA (g) 0.00 11.35 22.70 34.05 45.40 Absorbance at 260 nm 0.225 0.551 0.787 1.140 1.460 Using the slope and intercept of the calibration curve, determine the quantity of RNA in a sample that gives an absorbance of 0.782. mass= hp

Answer 1

m = 0.027 ug^-1

b = 0.2208

mass = 20.79 ug

Explanation

When absorbance values are plotted against the RNA values, the equation of best fit line obtained is : y = 0.027x + 0.2208

slope = m = 0.027 ug^-1

intercept = b = 0.2208

Given : absorbance of sample = 0.782 = y

From the equation of best fit line, x = (y - 0.2208) / 0.027

x = (0.782 - 0.2208) / 0.027

x = 20.79

mass of RNA = x = 20.79 ug