Stoichiometry Worksheet
TERM 4 REVISION PCY102A STOICHIOMETRY & ORGANIC CHEM Page |1 Stoichiometry Worksheet 1. Complete the following table. Substance Amount (g) Water H2O Methane CH4 Ammonia NH3 Octane C8H18 Acetic acid CH3COOH Ethanol CH3CH2OH Molar Mass (M) Number of atoms in the molecule Number of moles (n) of substance Number of molecules 3.2 2.7 0.056 2.34 27.3 6.0 x 1024 Remember ππ. ππ ππππ‘πππππ ππ΄ β¦where n is the number of moles and NA is Avogadroβs Number (6.02 x 1023). π= π π β¦where n is the no. of moles, m is the mass in g and M is the Molar Mass in g molβ1 2. Calculate the amount, in moles, of: (a) 46 g of water, H2O (b) 2.4 g of carbon dioxide, CO2 (c) 67 g of chlorine gas, Cl2 (d) 2.0 g of sodium chloride NaCl (e) 128 g of copper(II) sulfate pentahydrate, CuS04β5H20 π= TERM 4 REVISION PCY102A STOICHIOMETRY & ORGANIC CHEM 3. Complete the following table. Atomic Mass Isotopes Number Number Neon-20 10 20 Symbol No. Protons Page |2 No. Neutrons No. Electrons ππ πππ΅π Neon-22 Zinc-64 Zinc-68 Uranium-235 Uranium-238 Uranium-239 4.( a) Magnesium has three isotopes: 24Mg, 25Mg and 26Mg. If the relative amounts of each are 78.70%, 10.13% and 11.17% respectively, calculate the relative atomic mass of magnesium. (b) Chlorine is a gas containing approximately 76% of the isotope Cl-35 and 24% of the isotope Cl-37, calculate the relative atomic mass of chlorine. 5. Magnesium reacts with oxygen gas to form magnesium oxide: (a) Write a balanced equation for this reaction. (b) How any moles of magnesium are required to react fully with every mole of oxygen? (c) How much magnesium oxide can be produced from 15 g of magnesium? 6. Balance the equations and then determine the number of moles of each chemical which reacts or is produced. (a) __ N2 (g) + __ CI2 (g) β __ NCI3 (l) n (N2) (i) (ii) (iii) 4.0 mol 3.2 mol n (Cl2) n (NCl3) 6.0 mol 4.0 mol TERM 4 REVISION (b) PCY102A STOICHIOMETRY & ORGANIC CHEM Page |3 __ C2H8 (g) + __ O2 (g) β __ CO2 (g) + __ H2O (l) n (C2H8) (i) n (CO2) n (H2O) 0.3 mol (ii) (iii) n (O2) 4.0 mol 6.0 mol 7. When solid sodium and chlorine gas are reacted, table salt is produced. (a) Write the balanced equation for the reaction. (b) If 15 g of sodium were used, how much table salt would be produced? 8. Find the empirical formula for the following compounds. (a) 43.7% P, 56.3% O (b) 24.4% C, 3.39% H, 72.2% Cl (c) 50.5% C, 5.26% H, 44.2% N 9. A compound has an empirical formula C5H11. If 0.0275 mol of the compound has a mass of 3.91 g, what is the molecular formula? 10. Determine the molecular formula for a compound whose molecular mass is 174 g/mol and its percentage composition is 41.4% carbon, 3.4% hydrogen, and 55.2% oxygen. TERM 4 REVISION PCY102A STOICHIOMETRY & ORGANIC CHEM Page |4 Organic Chemistry Worksheet A. Complete the table below Name Methane Ethane Molecular Formula C3H8 C4H10 Pentane Hexane C6H14 C7H16 C 8H18 C 9H20 C10 H22 C11 H24 C12 H26 B. Draw the structural formula and determine the molecular formula that represents compound 1-heptyne. C. Draw the molecules of butane and 2-butene. What makes them different? D. Draw the structural formula forβ¦ (i) undecane (ii) hexane (iii) nonene (iv) 3,3-dimethylbutyne (v) pentanol (vi) pentan-2-ol (vii) 2-methylpropan-1-ol (viii) 2,2-dimethylbutan-1-ol E. Determine the molecular formula for D. above. TERM 4 REVISION PCY102A STOICHIOMETRY & ORGANIC CHEM Page |5 F. Given the structural formula, identify the molecule. (i) (ii) H (iii) (iv) (v) (vi) (vii) (vii) G. Ethanol and carbon dioxide are produced by the fermentation of sugar (C6H12O6) with yeast. Determine the balanced equation for this reaction. H. Write molecular and structural formulas for: (i) methanoic acid (ii) ethanoic acid (iii) ethyl dodecanoate (iv) methyl propanoate (v) 3-methyl-butyl ethanoate TERM 4 REVISION PCY102A STOICHIOMETRY & ORGANIC CHEM Page |6 I. What is an isomer? Draw two possible isomers of C4H8. J. Name and draw the expanded structural formula of the esters formed in the table below CARBOXYLIC ACID COMPONENT OF ALCOHOL COMPONENT OF ESTER ESTER Acetic acid (ethanoic acid) Propionic acid (propanoic acid) Formic acid (methanoic acid) Ethanol Ethanol n-butanol (Butan-1-ol) TERM 4 REVISION PCY102A STOICHIOMETRY & ORGANIC CHEM Page |7
© Copyright 2024