The ratio of carbon-13 to carbon-12 in a sample of material from a CAM plant is 124:10,000. The same ratio for the reference standard is 125:10,000. Delta (δ) is thus _______ per thousand.
A) ‒124
B) ‒8
C) ‒1
D) 1

Question

Quizplus · Accepted Answer

Delta (δ) is calculated using the formula: δ = [(R_sample/R_standard) - 1] * 1000, where R is the ratio of carbon-13 to carbon-12. For the sample, R_sample = 124/10,000, and for the standard, R_standard = 125/10,000. δ = [(124/125) - 1] * 1000 = ‒8 per thousand.

The Ratio of Carbon-13 to Carbon-12 in a Sample of Material