How many mL of alcohol and how many mL of water are needed to prepare a 35.0%
alcohol solution containing 15.0 mL

Here we want to mix a volume of water and a volume of alcohol in such a way that we end with a 35.0% alcohol solution.

We will conclude that we must use 9.75 mL of water and 5.25 mL of alcohol.

Now let's see how to get the solution:

First, we should define the variables:

We want to have a 15 mL solution, then we will have:

x + y = 15 mL

And the 35% of this must be alcohol, then we will have that the quotient between the volume of alcohol and the total volume should be equal to 0.35

y/15mL = 0.35

That can be rewritten as:

y = 0.35*15ml = 5.25mL

Now we can reaplace this in the first equation to get the volume of water that we must use:

x + y = 15mL

x + 5.25mL = 15mL

x = 15mL - 5.25 mL = 9.75mL

So we can conclude that we must use 9.75 mL of water and 5.25 mL of alcohol.

If you want to learn more, you can read:

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15.00 ml ROH + 27.86 ml H₂O => 42.86 ml of solution

Explanation:

Assuming the 15.0 is the volume of alcohol ...

Vol ROH = 15.00 ml = 35% of X where X = total volume of solution

X = 15.00 ml/0.35 = 42.86 ml total volume of solution

∴ Volume of water in 42.86 ml of solution = 42.86 ml - 15.00 ml = 27.86 ml

each  column  of the  table  is called a group. elements in a group share similar properties. groups are  read  from  top  to  bottom. metal. metalloid. nonmetal. solid. liquid. gas. fe. hg. o.  2. 3. 4. 5. 6. 7. 8. 9.  2. beryllium. 9.012. 4.  sodium. 22.990.  11. 3.  magnesium. 24.305.  12.  potassium. 39.098.  19. 4.  calcium. 40.078.  20. i guess  i