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This quiz contains 12 questions from a mix of 1 subtopics.

Phosphorus reacts with oxygen to give a compound that is 43.7% phosphorus and 56.3% oxygen.

What is the empirical formula of the compound?

PO

P1O2.5

P2O5

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What is the empirical formula of a compound that contains 15.9% boron and 84.1% fluorine?

B3F

BF3

B2F3

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What is the empirical formula of a compound that contains 46.3% lithium and 53.7% oxygen?

Li2O

Li2O4

Li2O2

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Compound X has the following percentage by mass composition: C: 40.0%; H: 6.7%; O: 53.3%. 

Deduce the empirical formula of compound X.

CHO

CH2O

C6HO8

C2H4O

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Compound X has an empirical formula of CH2O and a relative molecular mass of 180.0. 

Deduce the molecular formula of compound X.

C12H12O12

C6H6O6

6(CH2O)

C6H12O6

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Compound Y contains 52.2 g of carbon, 13.0 g of hydrogen and 34.8 g of oxygen.

Deduce the empirical formula of compound Y.

C3H6O2

CH3O

C2H6O

C2H3O

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Select the correct formula for hydrated copper(II) sulfate.

CuSO4•5H2O

CuSO45H2O

CuSO4

CuSO4 + 5H2O

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Select the correct formula for anhydrous cobalt(II) chloride.

CoCl2

CoCl22H2O

Co2Cl22H2O

Co2Cl2

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A 1.20 g sample of hydrated tin chloride is heated, causing it to decompose and form 1.01 g of anhydrous tin chloride:

SnCl2nH2O ➔ SnCl2 + nH2O

Work out the value of n.

The formula of the hydrated compound is SnCl2H2O

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3.74 g of hydrated copper sulfate is heated to form 2.39 g of anhydrous copper sulfate:

CuSO4nH2O ➔ CuSO4 + nH2O

Work out the value of n.

The formula of the hydrated compound is CuSO4H2O

5

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4.92 g of hydrated magnesium sulfate was heated to remove the water, producing 2.40 g of anhydrous magnesium sulfate.

Work out the value of n.

The formula of the hydrated compound is MgSO4H2O

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A 4.31 g sample of hydrated Na2CO3 is heated to remove the water. The mass of the resulting anhydrous compound is 3.22 g.

What is the formula of the hydrated compound?

The formula of the hydrated compound is Na2CO3H2O

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