Find out the amount of the elements

[Say17]

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.

 

[Borek]

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:

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?