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# Percentage Masses (CHEMISTRY HELPP!!)

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1. The element tellurium, Te, reacts with chlorine to form a single solid product, with a relative formula mass of 270. The product contains 52.6% chlorine by mass.

I understand to a certain extent how to solve it, i just do not understand why i am doing the things i am doing.
2. First of all, you have not included the question! Anyway, the following may help.

Te Cl4 has a molecular mass made up as 4 x 35.5 + 128.
the Chlorine makes up 142 out of the 270. 142/270 X 100 = 53.6 (3 sf) which is where the 52.6 comes from.

For a more complete answer, try posing the question.
3. (Original post by nerak99)
First of all, you have not included the question! Anyway, the following may help.

Te Cl4 has a molecular mass made up as 4 x 35.5 + 128.
the Chlorine makes up 142 out of the 270. 142/270 X 100 = 53.6 (3 sf) which is where the 52.6 comes from.

For a more complete answer, try posing the question.
oops sorry . I need to find the molecular formula.
4. So in this case you would find 53.6% of 270 and say OK 52.6% of 270 = 142. How many Cl is this? 142/35.5=4.000 so we must be Cl4. How much is left? 47.4%. 47.4% of 270 =127.98 ~ 128 which is one Te and hence we have TeCl4

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