The Mole Concept, Chemical Formula and Equation

Enrichment Corner 3:1. When steam is passed over a hot iron metal, hydrogen gas and iron(III) oxide are formed. What is the mass of steam required to react completely with 100 g of iron? [Relative atomic mass: H = 1, O = 16, Fe = 56]2. Lithium hydroxide, LiOH is used to remove carbon dioxide … Read more

Question:6. Figure 2 shows the aerobic respiration in our body cells to produce energy from glucose, C6H12O6. Write a balanced chemical equation for the process of aerobic respiration.7. Iron(II) sulphate heptahydrate, FeSO4.7H2O is often used to treat anaemic patients suffering from the lack of iron mineral.(a) What is the molar mass of iron(II) sulphate heptahydrate?(b) … Read more

Question:Refer to the Data Table of Elements on page 276.[Avogadro constant, NA : 6.02 × 1023 mol–1; Molar volume = 22.4 dm3 mol–1 at STP or 24 dm3 mol–1 at room conditions]1. What is meant by molar mass and molar volume?2. What is the relationship between Avogadro constant, number of particles and number of moles?3. … Read more

Question:1. Write the chemical equations for the following reactions:(a) Copper + Silver nitrate solution → Copper(II) nitrate solution + Silver(b) Hot zinc metal will react with chlorine gas to produce solid zinc chloride2. Decomposition of hydrogen peroxide, H2O2 occurs according to the following equation:2H2O2(l) → 2H2O(l) + O2(g)(a) What are the products of the decomposition … Read more

Activity 3.21:Creating a computer worksheet the laboratory. Decomposition of potassium chlorate(V), KClO3 by heat is often used to produce oxygen gas in the laboratory. 2KClO3(s) → 2KCl(s) + 3O2(g)Assume you are a laboratory assistant. You are required to prepare different amounts of oxygen gas from time to time. Repeated calculations using chemical equations can be simplified … Read more

Activity 3.20:Solving numerical stoichiometry problems [Relative atomic mass: H = 1, C = 12, O = 16, Cl = 35.5, Ca = 40, Fe = 56, Zn = 65; Avogadro constant, NA : 6.02 × 1023 mol–1; Molar volume = 22.4 dm3 mol–1 at STP or 24 dm3 mol–1 at room conditions]1. Decomposition of calcium … Read more

Activity 3.18:Aim: To write balanced chemical equations.Materials: Copper(II) carbonate powder, CuCO3, concentrated hydrochloric acid, HCl, concentrated ammonia solution, NH3, lead(II) nitrate solution, Pb(NO3)2, potassium iodide solution, KI and limewaterApparatus: Test tubes, delivery tube and rubber stopper, test tube holder, Bunsen burner, 10 cm3 measuring cyclinder, test tube stoppers and glass tubeProcedure:(A) Heating of copper(II) carbonate, … Read more

Aktivity 3.17:Balancing chemical equations 1. Write a balanced chemical equation for each of the following reactions: (a) Nitrogen gas + Hydrogen gas → Ammonia gas(b) Sodium metal + Water → Aqueous solution of sodium hydroxide + Hydrogen gas(c) Solid copper(II) carbonate decomposes into solid copper(II) oxide and carbon dioxide gas when heated.(d) Burning of aluminium … Read more

Test Yourself 3.3:1. What is meant by empirical formula and molecular formula?2. Caffeine, C8H10N4O2 is a natural stimulant found in coffee, tea and cocoa. What is the empirical formula of caffeine?3. Calcium carbonate and sodium fluoride are two compounds found in toothpaste. Write the chemical formulae of both compounds.4. A sample of 5.04 g of … Read more

Activity 3.16:Naming compounds 1. Name the ionic compounds with the following formulae: (a) CaCl2(b) KBr(c) Mg(NO3)2(d) ZnCO3(e) Na2SO4  (f) NH4Cl2. Name the molecular compounds with the following formulae: (a) NO (b) CO2(c) SO3(d) CCl4(e) BF3(f) CS23. The molecule of a compound consists of two nitrogen atoms and three oxygen atoms. Name the compound. Answer:1. (a) … Read more