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### Answering a Question without amount of elements

Posted: Tue Nov 12, 2019 12:38 pm
When you don't get the amount in grams of each element in the question, what is the best way to find out those amounts? You would get the molar mass of the compound and the amounts of the other molecules in the equation. There was a question like this on the midterm.

### Re: Answering a Question without amount of elements

Posted: Tue Nov 12, 2019 3:03 pm
You find the moles of the whole substance they are involved in and then multiply by the total number of the element is in the compound for example if its H2O and you want to get grams of hydrogen you find the moles of H2O and then multiply by 2 because 2 hydrogens are in H2O and then multiply by the molar mass of Hydrogen to get the grams of hydrogen. Rinse and repeat for the other elements unless two pieces of the equation have the same element then you have to find the weight of everything else first then subtract that from the total weight to give you the weight of that last element.