On-line calculations Quiz 8. Deducing empirical and molecular formula (using mole concept)

0.55g of boron combined with 1.2g of oxygen. Deduce the empirical formula of boron oxide. (relative atomic masses, A_r: B = 11, O = 16) [efm-1]
1.35g of aluminium was burned in excess fluorine to form 4.2g of aluminium fluoride. Deduce the empirical formula of aluminium fluoride. (relative atomic masses, A_r: Al = 27, F = 19) [efm-2]
3.4g of an unusual carbon oxide contained 1.8g of carbon. Deduce the empirical formula of the carbon oxide. (relative atomic masses, A_r: C = 12, O = 16) [efm-3]
In an experiment 3.175g of copper combined with 0.400g of oxygen. What is the empirical formula of the copper oxide? (relative atomic masses, A_r: Cu = 63.5, O = 16) [efm-4]
8.875g of chlorine combined with 14.25g of fluorine. What is the formula of the chlorine fluoride? (relative atomic masses, A_r: Cl = 35.5, F = 19) [efm-5]
A gas formed by the combination of hydrogen and sulphur consited of 5.88% hydrogen and 94.12% sulphur. What is its empirical formula? (relative atomic masses, A_r: H = 1, S = 32) [efm-6]
5.08g of iodine combined with 1.6g of oxygen. What is the formula of the iodine oxide? (relative atomic masses, A_r: I = 127, O = 16) [efm-7]
2.8g of lithium was heated in a stream of air forming 6.0g of lithium oxide. What is its formula? (relative atomic masses, A_r: Li = 7, O =16) [efm-8]
A iron-copper sulphide ore consisted of 30.5% iron, 34.6% copper, and 34.9% sulphur. What is the empirical formula of the ore? (relative atomic masses, A_r: Fe = 56, Cu = 63.5, S = 32) [efm-9]
0.48g of magnesium combined with 3.20g of bromine. What is the formula of magnesium bromide? (relative atomic masses, A_r: Mg = 24, Br = 80) [efm-10]
0.7g of nitrogen combined with 5.325g of chlorine. Deduce the formula of nitrogen chloride. (relative atomic masses, A_r: N = 14, Cl = 35.5) [efm-11]
Fluorine oxide consists of 70.4% fluorine and 29.6% oxygen by mass. Deduce the formula of fluorine oxide. (relative atomic masses, A_r: F = 19, O = 16) [efm-12]
47.6g of uranium combined with 22.8g of fluorine. What is the empirical formula of this uranium fluoride? (relative atomic masses, A_r: U = 238, F = 19) [efm-13]
10.35g of lead was heated in excess oxygen. If 11.95g of a lead oxide was formed, deduce its empirical formula. (relative atomic masses, A_r: Pb = 207, O = 16) [efm-14]
10.8g of aluminium combined with 19.2g of sulphur. What is the empirical formula of aluminium sulphide? (relative atomic masses, A_r: Al = 27, S = 32) [efm-15]
A hydrocarbon of molecular mass 30 consisted of 80% carbon and 20% hydrogen by mass. Deduce the molecular formula of the hydrocarbon. (relative atomic masses, A_r: C = 12, H = 1) [efm-16]
6g of carbon combines with 71g of chlorine. What is the formula of the carbon chloride? (relative atomic masses, A_r: C = 12, Cl = 35.5) [efm-17]
An organic compound consisted of 52.18% carbon, 13.04% hydrogen and 34.78% oxygen by mass. Deduce its empirical formula. (relative atomic masses, A_r: C = 12, H = 1, O = 16) [efm-18]
An chlorinated hydrocabon molecule consisted of 37.21% carbon, 7.75% hydrogen and 55.04% chlorine by mass. Deduce its empirical formula. (relative atomic masses, A_r: C = 12, H = 1, Cl = 35.5) [efm-19]
A calcium mineral consisted of 29.4% calcium, 23.5% sulphur and 47.1% oxygen by mass. Calculate the empirical formula of the mineral. (relative atomic masses, A_r: Ca = 40, S = 32, O = 16) [efm-20]
A salt consisted of 27.06% sodium, 16.47% nitrogen and 56.47% oxygen by mass. Deduce the formula of the salt. (relative atomic masses, A_r: Na = 23, N = 14, O = 16) [efm-21]
A brominated hydrocarbon consisted of 12.77% carbon, 2.13% hydrogen and 85.10% bromine by mass. If its molecular mass is 188, deduce the molecular formula of the molecule. (relative atomic masses, A_r: C = 12, H = 1, Br =80) [efm-22]
It was found that 24g of carbon was combined with 5g of hydrogen in a hydrocarbon. If its molecular mass was 58, what is its molecular formula? (relative atomic masses, A_r: C = 12, H = 1) [efm-23]
A hydrocarbon consisted of 92.3% carbon and 7.7% hydrogen. If its molecular mass is 78, work out its molecular formula. (relative atomic masses, A_r: C = 12, H = 1) [efm-24]
A carbohydrate on analysis consisted of 40.00% carbon, 6.67% hydrogen and 53.33% oxygen. If its molecular mass is 180, deduce the molecular formula of the carbohydrate. (relative atomic masses, A_r: C = 12, H = 1, O = 16) [efm-25]
7.75g of an alcohol consisted of 3.00g carbon, 0.75g hydrogen and 4.00g oxygen. If its molecular mass is 62, work out the molecular formula. (relative atomic masses, A_r: C = 12, H = 1, O = 16) [efm-26]
An alcohol consisted of 39.13% carbon, 8.70% hydrogen and 52.17% oxygen. If its molecular mass is 92, deduce its molecular formula. (relative atomic masses, A_r: C = 12, H = 1, O = 16) [efm-27]
In an experiment 6g of carbon combined with 19g of fluorine. Calculate the molecular formula of the compound formed if the molecular mass of it is 100. (relative atomic masses, A_r: C = 12, F = 19) [efm-28]
A compound of hydrogen and oxygen was made up of 0.5g hydrogen and 8g of oxygen. What is its empirical formula? (relative atomic masses, A_r: H = 1, O = 16) [efm-29]
A lithium compound consisted of 7g of lithium combined with 16g of sulphur and 32g of oxgen. What is the empirical formula of the compound? (relative atomic masses, A_r: Li = 7, S = 32, O = 16) [efm-30]
58g of a sodium phosphate salt consisted of 34.5g of sodium, 15.5g of phosphorus and 32.0g of oxygen. What is the simplest formula of the compound? (relative atomic masses, A_r: Na = 23, P = 31, O = 16) [efm-31]
A sodium compound consisted of 46g of sodium combined with 254g of iodine and 128g of oxygen. What is the compounds empirical formula? (relative atomic masses, A_r: Na = 23, I = 127, O = 16) [efm-32]
16g of copper, after heating in oxygen, formed 20g of a copper oxide. What is the formula of the oxide? (relative atomic masses, A_r: Cu = 64, O = 16) [efm-33]
An oxide of carbon consisted of 3g of carbon combined with 4g of oxygen. What is the formula of the oxide? (relative atomic masses, A_r: C = 12, O = 16) [efm-34]
1.95g of potassium combined with 4.00g of bromine. What is the empirical formula of the compound? (relative atomic masses, A_r: K = 39, Br = 80) [efm-35]
5g of calcium on heating in oxygen formed 7g of calcium oxide. What is the simplest formula of calcium oxide? (relative atomic masses, A_r: Ca = 40, O = 16) [efm-36]
13g of zinc combined with 6.4g of sulphur. What is the empirical formula of zinc sulphide? (relative atomic masses, A_r: Zn = 65, S = 32) [efm-37]
An oxide of copper contained 80% copper and 20% oxygen by mass. What is the formula of the copper oxide? (relative atomic masses, A_r: Cu = 64, O = 16) [efm-38]
If magnesium oxide consists of 60% magnesium and 40% oxygen, what is its simplest formula? (relative atomic masses, A_r: Mg = 24, O = 16) [efm-39]
2.3g of sodium combined with 1.6g of sulphur. What is the formula of sodium sulphide? (relative atomic masses, A_r: Na = 23, S = 32) [efm-40]
In an experiment 1.28g of copper combined with 0.16g of oxygen. What is the formula of the copper oxide? (relative atomic masses, A_r: Cu = 64, O = 16) [efm-41]
13.8g of sodium combined with 6.2g of phosphorus. What is the formula of sodium phosphide? (relative atomic masses, A_r: Na = 23, P = 31) [efm-42]
10g of calcium combined with 40g of bromine. What is the formula of calcium bromide? (relative atomic masses, A_r: Ca = 40, Br = 80) [efm-43]
22g of boron combined with 114g of fluorine. What is the empirical formula of boron fluoride? (relative atomic masses, A_r: B = 11, F = 19) [efm-44]
1.2g of titanium, after heating in oxygen, formed 2.0g of a titanium oxide. What is the empirical formula for the titanium oxide? (relative atomic masses, A_r: Ti = 48, O = 16) [efm-45]
0.800g of magnesium reacted with 8.467g of iodine. Calculate the empirical formula for magnesium iodide.? (relative atomic masses, A_r: Mg = 24, I = 127) [efm-46]

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On-line calculations Quiz 8. Deducing empirical and molecular formula (using mole concept)

Type in an answer and click CHECK, no need for units, lower case only. All GCSE Chemistry, Earth Science and Radioactivity Quizzes"Doc Brown's Chemistry Clinic" EMAIL query?comment, quote Q ref [efm-xx]) (01-06-09)