11. Group 17
A section of Chemistry, 9701
Listing 10 of 617 questions
Aqueous solutions of copper(salts contain the blue-coloured [Cu(H2O)6]2+ complex ion. Separate portions of this blue solution react with aqueous sodium hydroxide and with concentrated hydrochloricacid. Give the following information for each of these reactions. ● ● reaction with aqueous sodiumhydroxide ionic equation type of reaction colour and state of the copper-containing product ● ● reaction with concentrated hydrochloricacid ionic equation type of reaction colour and state of the copper-containing product  Chloride ions can be identified using aqueous silvernitrate, AgNO3. Ag++ Cl –AgCl 0.303 g of a chloride of sulfur is completely hydrolysed with water. All the chlorine atoms present in the chloride of sulfur are converted into chloride ions. The solution is diluted to 100.0 cm3. A 25.00 cm3 sample of this solution is titrated with 0.0500 mol dm–3 AgNO3. The titration requires 22.40 cm3 of 0.0500 mol dm–3 AgNO3. Calculate the empirical formula of the chloride of sulfur. Show all your working.  empirical formula of chloride of sulfur = 
9701_s19_qp_41
THEORY
2019
Paper 4, Variant 1
View
Complete the electronic configuration of the copper(ion. 1s22s22p6 State the colour of the solutions containing the following ions. ● [Cu(H2O)6]2+● [CuCl 4]2– Octahedral complexes of Cu2+ with different ligands can have different colours. Explain why. Copper(and silver(salts are colourless. Suggest why. Consider the following two equilibria and associated data values at 298 K. AgBrAg++ Br –equilibrium1 Ksp = 5.0 × 10–13 mol2 dm–6 Ag++ 2NH3[Ag(NH3)2]+equilibrium2 Kstab = 1.7 × 107 mol–2 dm6 The equilibrium constant for equilibrium1 is the solubility product, Ksp, of AgBr. The equilibrium constant for equilibrium2 is the stability constant, Kstab, for the formation of [Ag(NH3)2]+. Calculate the solubility of AgBr at 298 K in mol dm–3.  solubility of AgBr = mol dm–3 Use Le Chatelier’s principle as applied to equilibria 1 and 2 to suggest why AgBrdissolves in concentrated NH3. Use equilibria1 and 2 to construct an equation for the reaction of AgBrwith concentrated NH3. This is equilibrium3. equilibrium3 Write an expression for the equilibrium constant of equilibrium 3, Keq3, in terms of Ksp for equilibrium1 and Kstab for equilibrium2. Keq3 =  Define the term standard electrode potential, E o. Complete and label the diagram to show how the standard electrode potential, E o, of Ag+/ Agcould be measured under standard conditions.  Use the Data Booklet to label the diagram in to show ● ● which is the positive electrode, ● ● the direction of electron flow in the external circuit when a current flows.  
9701_s19_qp_42
THEORY
2019
Paper 4, Variant 2
View
Aqueous solutions of copper(salts contain the blue-coloured [Cu(H2O)6]2+ complex ion. Separate portions of this blue solution react with aqueous sodium hydroxide and with concentrated hydrochloricacid. Give the following information for each of these reactions. ● ● reaction with aqueous sodiumhydroxide ionic equation type of reaction colour and state of the copper-containing product ● ● reaction with concentrated hydrochloricacid ionic equation type of reaction colour and state of the copper-containing product  Chloride ions can be identified using aqueous silvernitrate, AgNO3. Ag++ Cl –AgCl 0.303 g of a chloride of sulfur is completely hydrolysed with water. All the chlorine atoms present in the chloride of sulfur are converted into chloride ions. The solution is diluted to 100.0 cm3. A 25.00 cm3 sample of this solution is titrated with 0.0500 mol dm–3 AgNO3. The titration requires 22.40 cm3 of 0.0500 mol dm–3 AgNO3. Calculate the empirical formula of the chloride of sulfur. Show all your working.  empirical formula of chloride of sulfur = 
9701_s19_qp_43
THEORY
2019
Paper 4, Variant 3
View
An aqueous solution of cobalt(contains the [Co(H2O)6]2+ complex ion. Define the term complex ion. Samples of [Co(H2O)6]2+ are reacted separately with aqueous sodiumhydroxide and with an excess of aqueous ammonia. Give the following information about these reactions. ● ● the reaction of [Co(H2O)6]2+ with aqueous sodiumhydroxide colour and state of the cobalt-containing species ionic equation type of reaction ● ● the reaction of [Co(H2O)6]2+ with an excess of aqueous ammonia colour and state of the cobalt-containing species ionic equation type of reaction  When concentrated hydrochloricacid is added to a solution containing [Co(H2O)6]2+, a blue solution of [CoCl 4]2– is formed and the following equilibrium is established. [Co(H2O)6]2+ + 4Cl – [CoCl 4]2– + 6H2O Use Le Chatelier’s principle to suggest the expected observations when silvernitrate solution is added dropwise to the blue solution of [CoCl 4]2–. Explain your answer. The [Co(NH3)3Cl 3] complex shows stereoisomerism. Complete the three-dimensional diagrams to show the two isomers of [Co(NH3)3Cl 3]. Suggest the type of stereoisomerism. Co Co type of stereoisomerism  CompoundX, C6H18N4, is a tetradentate ligand. H2N NH2 N H X H N Suggest why one molecule of X can form four dative bonds. C6H18N4 reacts with aqueous cobalt(ions, [Co(H2O)6]2+, in a 1 : 1 ratio to form a new complex ion. Construct an equation for this reaction. 
9701_s20_qp_41
THEORY
2020
Paper 4, Variant 1
View
An aqueous solution of cobalt(contains the [Co(H2O)6]2+ complex ion. Define the term complex ion. Samples of [Co(H2O)6]2+ are reacted separately with aqueous sodiumhydroxide and with an excess of aqueous ammonia. Give the following information about these reactions. ● ● the reaction of [Co(H2O)6]2+ with aqueous sodiumhydroxide colour and state of the cobalt-containing species ionic equation type of reaction ● ● the reaction of [Co(H2O)6]2+ with an excess of aqueous ammonia colour and state of the cobalt-containing species ionic equation type of reaction  When concentrated hydrochloricacid is added to a solution containing [Co(H2O)6]2+, a blue solution of [CoCl 4]2– is formed and the following equilibrium is established. [Co(H2O)6]2+ + 4Cl – [CoCl 4]2– + 6H2O Use Le Chatelier’s principle to suggest the expected observations when silvernitrate solution is added dropwise to the blue solution of [CoCl 4]2–. Explain your answer. The [Co(NH3)3Cl 3] complex shows stereoisomerism. Complete the three-dimensional diagrams to show the two isomers of [Co(NH3)3Cl 3]. Suggest the type of stereoisomerism. Co Co type of stereoisomerism  CompoundX, C6H18N4, is a tetradentate ligand. H2N NH2 N H X H N Suggest why one molecule of X can form four dative bonds. C6H18N4 reacts with aqueous cobalt(ions, [Co(H2O)6]2+, in a 1 : 1 ratio to form a new complex ion. Construct an equation for this reaction. 
9701_s20_qp_43
THEORY
2020
Paper 4, Variant 3
View
Questions Discovered
617