Chemistry Find out the amount of the elements

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To find the number of moles in 27g of water, the calculation involves determining the molar mass of H2O, which is 18.02 g/mol. Dividing 27g by 18.02 gives 1.5 moles of water. To find the grams of each element, calculate the mass of hydrogen and oxygen in water based on their proportions in the formula. For every mole of water, there are 2 grams of hydrogen and 16 grams of oxygen, so for 1.5 moles, multiply these amounts accordingly. Understanding the molar mass and the composition of water is essential for accurate calculations.
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Homework Statement
From the following list, indicate the condition(s) that will enable you to obtain at least 27 g of water.
Relevant Equations
H2O = 2*1.01 + 16 = 18.02
Hi everyone,

I just don't get it how to compute the following task. First I have to find out many moles are in 27g of Water.

H2O = 2*1.01 + 16 = 18.02

27g/18.02 = 1.5mol but afterwards how do I find each elements gram?

d is the correct answer.

Image 18.06.23 at 14.34.jpeg
 
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Many ways to skin that cat.

You can start with the reaction equation and treat a,b,c,d as input into a limited reagent problem.

You can calculate mass of hydrogen and oxygen present in water. That's what the formula tells you:

Say17 said:
H2O = 2*1.01 + 16 = 18.02

This is basically what you need - molar mass is sum of masses of all elements involved. How many grams of hydrogen per mole of water? What if you have 1.5 times the amount?
 

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