# Chemistry/Math

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If a doctor tells you to drink 1 liter of water per day, answer the following questions(assuming the density of water to be 1g/mL):
1. The number of grams of water per day?
2.The number of molecules of oxygen per day?
3. The number of atoms of oxygen per day?
Please show how you arrived at these answers so that I may learn how to solve these kinds of problems in the future... Thanks!

• Chemistry/Math -

1. density of water is 1 g/mL. 1L = 1000 mL.
mass = volume x density
mass = 1000 mL x 1 g/mL = ??

2&3. Convert ?? grams/day to moles. moles = grams/molar mass H2O. There are 6.022 x 10^23 molecules of water in 1 mole H2O and there is 1 atom oxygen in 1 molecule H2O. Can you take it from here?

• Chemistry/Math -

I think so could you critique this?
1. I came up with 1000grams of H20
2. 1 mole H20 X 6.022X10^23/1 mole H20=6.0222X10^23 Molecules Oxygen
3. 1 mole H20 x 1 atom of oxygen/1 mole H20= 1 atom of Oxygen

Is this correct I really am trying to learn and understand this so that I can succeed in my class not just this assignment. Your feedback is greatly appreciated Dr.BOB222 Thank You!

• Chemistry/Math -

So if i were asked for grams of Hydrogen per day?

it would be 1 mole H20 X 2 grams of H/1 mole H20

• Chemistry/Math -

1 is ok.
Your answer for 2 defines 1 mol as 6.022 x 10^23 molecules which we already know; in act, I wrote that in mu response.
You want 1000 g converted to moles.
1000 g x (1 mol H2O/18.015 g H2O) = ?? moles.
Then ?? moles H2O x (6.022 x10^23 molecules/1 mole H2O) = xx molecules H2O.

Then if you want to know atoms H, that is
xx molecules H2O x (2 atoms H/1 molecule H2O) = yy atoms hydrogen.
etc.