Which of the following is equivalent to the unit 1 ppm?
A) 1000 ppb
B) 0.0001%(w/w)
C) both 1000 ppb and 0.0001%(w/w)
D) neither 1000 ppb or 0.0001%(w/w)

Question

Quizplus · Accepted Answer

1 ppm means 1 part of a substance per million parts of the whole mixture. 
Similarly, 1 ppb means 1 part of a substance per billion parts of the whole mixture. 
Therefore, 1000 ppb means 1000 parts of a substance per billion parts of the whole mixture, which is equivalent to 1 part per million (ppm). 
0.0001% (w/w) means 0.0001 parts of a substance per 100 parts of the whole mixture (weight/weight), which is also equivalent to 1 part per million (ppm). Hence, both 1000 ppb and 0.0001% (w/w) are equivalent to 1 ppm.

Which of the Following Is Equivalent to the Unit 1