Question

concentration over 10 ppm .what does the ppm stands for

Answer 1

ppm stands for parts per million. One ppm is 1 part in 1 million or the value is equivalent to the absolute fractional amount multiplied by one million (10^6).

In terms of grams we can say, it is one gram of solute per million grams of sample solution.

The concentration of the particular substance is very low but even then it may be considered as a significant amount. E.g. Used to represent pollution of gases, contamination of water etc.