Question

Can someone explain this question to me? I know how to do the work but I just don't know what it's asking me to do, thanks.

When a 14.2g sample of mercury (II) oxide is decomposed into its elements by heating, 13.2g Hg is obtained. What is the percent composition of the compound?

Answer 1

Mercury oxide is HgO

If you want the percent composition of each element, given that Hg=13.2g

just do 13.2/14.2

and 1/14.2 for oxygen

Answer 2

But I don't know what to do with the given grams and I'm not sure what the question is asking me to find.

Answer 3

@dtan5457

Answer 4

They are asking you for the percent composition per element in the compound

in this case it's HG and O

Answer 5

For HG it's 13.2/14.2

For O it's 1/14.2

convert to percentages

Answer 6

I don't get that lol. I mean, I learned that to find percent comp. you do mass of element divided by mass of compound times 100 to find the mass of element.

So like, wouldn't I first find the mass of the whole compound?

Answer 7

"When a 14.2g sample of mercury (II) oxide "

Answer 8

I'm sorry I still don't get that part :(

Answer 9

That is the mass of the whole compound, 14.2 grams

Answer 10

Ohhhh ok!

Answer 11

So to find the mass of Hg aka the percent comp. of Hg, I would do 200.6/14.2 right?

Answer 12

it's mass of element/whole compound

For HG it's (13.2/14.2)x100

Answer 13

Wait, but what is 200.6 then? I got that off of the periodic table.

But so I'd get the answer by doing 13.2/14.2 times 100 correct?

Answer 14

So I got 92.96% as the answer. Is that correct?

Answer 15

yes

Answer 16

and oxygen would just be 100-92.96

Answer 17

I don't know where the 200 came from

Answer 18

Ohhhhhh okay! Omg thank you so much! :) And idk I think I musta did something wrong but still thanks a lot :) I appreciate it.

Answer 19

yw