what is the ratio of water drops to EDTA if 2 drops of EDTA was needed to change the color of 20 drops of water with unknown hardness?

a. 10
b. 5
c. 0.1
d. 1.0

please explain..

Let's see. Bob Pursley did one early this AM that was 3 drops to 20 drops, so 3:20 (6.7) was the answer. Wouldn't this be done the same way?

so would the answer be a. 10??

That looks right to me.

H2O/EDTA = 20/3 = 6.7

H2O/EDTA = 20/2 = 10

To find the ratio of water drops to EDTA drops, we need to divide the number of water drops by the number of EDTA drops.

According to the question, 2 drops of EDTA were needed to change the color of 20 drops of water.

So, the ratio would be calculated as follows:

Ratio = Number of Water Drops / Number of EDTA Drops

Ratio = 20 drops / 2 drops

Ratio = 10

Therefore, the ratio of water drops to EDTA drops is 10.

In other words, for every 1 drop of EDTA, you will need 10 drops of water.

The correct answer is (a) 10.