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1.What is the empirical formula of a substance composed of 56.6% potassium, 8.68% carbon, and 34.7% oxygen?

2. What is the empirical formula of a substance composed 49.89% strontium 13.67% carbon and 36.44% oxygen?

May 26th, 2015

1) Assume 100 grams of compound

then we have:

56.6g of Potassium

8.68g of Carbon

and 34.7g of Oxygen

using the atomic mas of each element we can find the number of moles of each element

K: 56.6g / 39.1 = 1.45 moles

C: 8.68g / 12 = 0.72 moles

O: 34.7g / 2.17 moles

NOW, divide by the lower, in this case 0.72

K: 1.45 /0.72 = 2

C: 0.72 70.72 = 1

O: 2.177 0.72 =3

The formula of teh compound is: K2CO3

2) Assume 100 grams of compound

49.89 g Strontioun

13.67g carbon

36.44g Oxygen

using the atomic mas of each element we can find the number of moles of each element

Sr: 49.89 g /87.62 = 0.57 moles

C:13.67g / 12 = 1.14 moles

O: 36.44g / 16=  2.28 moles

NOW, divide by the lower, in this case 0.57

Sr: 0.57 /0.57 = 1

C:1.14 /0.57 = 2

O: 2.28 /0.57 = 4

The empirical formula is: SrC2O4

May 26th, 2015

Thank you so much for your help.

May 26th, 2015

Hello, you just posted another question, I was answering when you change the type of question, I already have the answrr if you want, just select my bis in your question, I can explain very well the answer if you want. Best regards

May 27th, 2015

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May 26th, 2015
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May 26th, 2015
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