hi, if 5.00g of ethanol is added to 15.0g of water, what is the % concentration of ethanol in water? (% to sig fig)

To determine the % concentration of ethanol in water, we need to calculate the mass of ethanol and the total mass of the mixture.

Given:
Mass of ethanol = 5.00g
Mass of water = 15.0g

To find the % concentration, we can use the formula:

% Concentration = (Mass of solute / Total mass of solution) x 100

First, we need to find the total mass of the solution:
Total mass of the solution = Mass of ethanol + Mass of water

Total mass of the solution = 5.00g + 15.0g = 20.0g

Now we can calculate the % concentration of ethanol:
% Concentration = (5.00g / 20.0g) x 100

% Concentration = 0.25 x 100

% Concentration = 25%

Therefore, the % concentration of ethanol in water is 25% when rounded to the nearest significant figure.