## Test 1/ Question 8 [ENDORSED]

Alejandro Salazar 1D
Posts: 31
Joined: Fri Sep 29, 2017 7:05 am

### Test 1/ Question 8

I would really appreciate if someone could explain question number 8 on Test 1 (Wednesday Section).

What information are we supposed to know for this problem? How would I get the mass of the molecule?
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Nienjou Claire 1E
Posts: 30
Joined: Fri Apr 06, 2018 11:05 am

### Re: Test 1/ Question 8  [ENDORSED]

For this, you wouldn't need the mass of the molecule. The structures themselves give you the molecular formula since it shows you exactly how many of each element is in the molecule. You can literally count the how many of each element there are and that is basically the molecular formula. To get the empirical formula, just simplify the molecular formula to get the simplest ratios.

Luis Torres 1C
Posts: 30
Joined: Fri Apr 06, 2018 11:05 am

### Re: Test 1/ Question 8

I would solve this first by finding the molecular formula. Since the molecular formula is the actual number of elements in the molecule, you would simply count how many of each atom there are. For example, the second molecule has 2 hydrogen atoms and 2 oxygen atoms. So the molecular formula is H2O2. The empirical formula is the relative number of atoms present. To find this, divide all of the numbers by the lowest number- in this case, 2. This leaves only 1 of each, so the empirical formula is simply OH.

Tiffany Tufenkjian 1E
Posts: 30
Joined: Fri Apr 06, 2018 11:05 am

### Re: Test 1/ Question 8

You find the molecular formula by counting how many of each element there is and then simplify the molecular formula for the empirical formula. The mass is not needed.

Jaquelinne Rodriguez-Lopez 1L
Posts: 38
Joined: Mon Apr 09, 2018 1:38 pm
Been upvoted: 1 time

### Re: Test 1/ Question 8

you can find the molecular formula very easily by just counting how many of each element is present in the compound. to find the empirical formula, just simplify. if you can't simplify from the molecular formula, the molecular formula is also the empirical formula.

Jaquelinne Rodriguez-Lopez 1L
Posts: 38
Joined: Mon Apr 09, 2018 1:38 pm
Been upvoted: 1 time

### Re: Test 1/ Question 8

you can find the molecular formula very easily by just counting how many of each element is present in the compound. to find the empirical formula, just simplify. if you can't simplify from the molecular formula, the molecular formula is also the empirical formula.

Joshua Yang 1H
Posts: 22
Joined: Mon Jan 08, 2018 8:19 am

### Re: Test 1/ Question 8

here's the answer. All you need to do here is count how many atoms of each element you have on the molecule
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