# Question #c7380

##### 1 Answer

Sep 7, 2017

#### Answer:

1 ml

#### Explanation:

as you can you are going from 100 ppm to 0.2 ppm which is a lowering the concentration by a factor of 500. therefore you only need 1/500 of the designated volume which in this case is 1/500 of 500 which is 1.