if 5.00g of ethanol is added to 15.0g of water, what is the % concentration of ethanol is water?
To calculate the % concentration of ethanol in water, we need to determine the total mass of the solution and the mass of ethanol in the solution.
First, let's calculate the total mass of the solution. It is obtained by adding the mass of ethanol (5.00g) to the mass of water (15.0g):
Total mass of the solution = Mass of ethanol + Mass of water
= 5.00g + 15.0g
= 20.0g
Now, let's calculate the mass of ethanol in the solution:
% concentration of ethanol = (mass of ethanol / total mass of the solution) * 100
Substituting the values we've calculated:
% concentration of ethanol = (5.00g / 20.0g) * 100
= 0.25 * 100
= 25%
Therefore, the % concentration of ethanol in water is 25%.