Hi - I need help with the following questions:

Julie dissolved 20 g of sugar in a cup of water. The mass of the solution was 500 g.

What volume (mL) of water did Julie start with?

How did you determine the starting volume of water?

The density of the pure water she started with is 1.000 g/ml.

Divide water mass (480 g) by density to get volume, which in this case would 480 ml.

That is a very big cup! More like two.. a Starbuck's Grande

Thank you for this information.

Can you give me the formulas involved so I know how you got the answer?

It seems like the water mass was the mass of the solution minus the solute or 500-20 = 480. But how did you get the density of water = 1.000 g/ml?

These formulas would be helpful. Thanks again!

To determine the starting volume of water, you can use the principle of conservation of mass. The mass of the solution is the sum of the masses of the solute (sugar) and the solvent (water).

First, you need to find the mass of the sugar that was dissolved. In the given information, it is stated that Julie dissolved 20 g of sugar in a cup of water.

Next, you find the mass of the solvent (water) by subtracting the mass of the sugar from the mass of the solution. In this case, the mass of the solution is given as 500 g. So, we have:

Mass of water = Mass of solution - Mass of sugar
Mass of water = 500 g - 20 g
Mass of water = 480 g

Now, we need to convert the mass of water to volume (mL) using the density of water. The density of water is approximately 1 g/mL.

Volume of water (mL) = Mass of water (g) / Density of water (g/mL)
Volume of water (mL) = 480 g / 1 g/mL
Volume of water (mL) = 480 mL

Therefore, Julie started with 480 mL of water.