Dilution calculation: use the formula M1V1=M2V2
How many milliliters of 12 M HCl would be needed to make 200 mL of a 1.0 M HCl solution?
I got 16.67 mL HCl for this part but there's a secondary question.
It says: How much water would be used to make this solution?
I have no clue what to do for that. Help, please and thank you.
200*1 = x*12
x = 16.67 mL.
The problem states that you are making 200 mL; therefore, 16.67 comes from the 12 M stuff and 200-16.67 comes from added water. Technically, this isn't correct because the two solutions may not be additive but for dilution problems of dilute solutions these problems usually mean that we assume they are (exactly additive). The way we get around that, in real life, is we would add 16.67 mL of the 12 M stuff to a volumetric flask of exactly 200 mL, then add water to the mark to make the final solution exactly 200 mL. So how much water would we add. The answer is ABOUT 200-16.67. I think this problem wants that answer without the word about.:-)
To calculate the amount of water needed, we can use the formula for dilution:
M1V1 = M2V2
In this case, we have 12 M HCl (M1) and want to make a 1.0 M HCl solution (M2) with a final volume of 200 mL (V2). We can rearrange the formula to solve for V1, the volume of the starting solution (12 M HCl):
V1 = (M2V2) / M1
Plugging in the values, we get:
V1 = (1.0 M * 200 mL) / 12 M
V1 = 16.67 mL
So, you are correct that 16.67 mL of 12 M HCl is needed for the solution.
To find the amount of water needed, we can subtract the volume of the starting solution (V1) from the desired final volume (V2):
Amount of water = V2 - V1
Amount of water = 200 mL - 16.67 mL
Amount of water = 183.33 mL
Hence, you would need to use 183.33 mL of water to make the 1.0 M HCl solution.