Which of the following statements about the standard hydrogen electrode is not correct?
- A. The hydrogen gas is at a pressure of 1 atmosphere
- B. A solution containing 1 mol dm-3 of H+ (aq) ions is used
- C. A platinum electrode is used
- D. The temperature is kept at 20 °C
Alkanols can be manufactured from alkenes by the initial reaction of alkenes with
- A. bromine in tetrachloromethane
- B. concentrated tetraoxosulphate(VI) acid
- C. aqueous potassium tetraoxomanganate(VII).
- D. sodium hydroxide solution.
Which of the following compounds would react rapidly with bromine?
- A. Benzene
- B. Hexane
- C. Hexene
- D. Hexanol
What amount of electricity is required to deposit one mole of aluminium from a solution of AlCl3?
- A. One Faraday
- B. One ampere
- C. Three Faradays
- D. Three amperes
The following compounds are condensation polymers except
- A. nylon
- B. protein
- C. starch
- D. polyethene
The cleansing effect of soap is low in acidic water because of
- A. the formation of unionized fatty acid.
- B. increase in the pH of the soap molecules.
- C. anti-biodegradable effect of hydrogen ions
- D. the hardness of the acidic water.
Which of the following sugars is a product of the condensation of monosaccharides?
- A. galactose
- B. maltose
- C. glucose
- D. fructose
The by-product of fermentation of sugar is
- A. carbon(IV) oxide.
- B. ethanoic acid.
- C. propanol
- D. propan-1, 2, 3- triol.
(a) Describe the observation that would be made when—–
i. Sulphur is heated from room temperature till 1190C
ii. 50% trioxonitrate(V) acid acts on copper tunings
(b)i. State two gaseous pollutants that can be generated by burning coal.
ii. What gas is responsible for most of the explosions in coal mines?
iii. The mining of coal leads to environmental pollution. State two environmental effects of the mining activity.
iv. Explain briefly why coal burns more easily when it is in pieces than in lump form
v. Name the non-volitile residue after the destructive distillation of coal
(c)i. Describe a chemical test for water
ii.a. State the effect of boiling a temporary hard water
b. State the effect of adding sodium trioxocarbonate(IV) crystals to permanent hard water
iii. Write an equation for the process of boiling a temporary hard water
(a)i. State two conditions used in the Haber process
ii. Explain briefly the effect of increasing the pressure on the rate of reaction in the Haber process.
(b)i. A mixture of nitrogen(IV) oxide and oxygen is bubbled into warm water to produce
trioxonitrate(V) oxide, write a balanced chemical equation for the reaction.
ii. Using a balanced chemical equation only, explain what would happen if nitrogen(IV) oxide is bubbled into warm water.
iii.
Compare the gases evolved when trioxonitrate(V) acid decomposes under each of the following properties:
i. pH
ii. Solubility in water
iii. Reaction with carbon(II) oxide
(c)i. Name two oxides of sulphur
ii. Write a balanced equation for the reaction between each of the named oxides(Sulphur(IV) oxide, Sulphur (VI) oxide) and water
(d)i. Name one calcium compound
a, Used to dry ammonia gas
b. Used in the manufacture of cement
c. That causes hardness in water
d. Name one calcium compound
(a)i. Define an acid according to the Lewis concept
ii. Give one example of a Lewis acid
(b) Explain salting out in soap preparation
(c) State the reagent and condition necessary for the following conversion
H−C≡C−H→Ag−C≡C−Ag
(d) What is the percentage abundance of an isotope?
(e)i. Why does the element with atomic number 18 not have an oxide?
ii. Explain why chlorine(I) oxide has a low melting point
(f). Describe a test to distinguish between concentrated HNO3 and concentrated H2SO4
(g) State two differences between an electrochemical cell and an electrolytic cell
(h) How does the trend in ionization energy affect the reactivity of group 1 elements?
(i).Define the term molecular formula
(j) State which of the gases H2 and NH3 would deviate more from ideal behaviour. Give reasons for the answer stated above
(a) (i) Define the term Avogadro’s number.
(ii) If 2.30 g of an oxide of nitrogen, x, contains 3.01 x 10\(^{22}\) molecules, calculate the molar mass of x.
(iii) Deduce the formula of x. N, =6.02 x 10″, N =14.0, O = 16.0]
(b)(i) Describe briefly what happens when each of the following substances are added to water:
(I) CCI\(_{4}\); (II) SiCI\(_{4}\),
(ii) Explain briefly why the reactions in (a)(i), (b)(i), (I) and (b)(ii) (II) are different Study the diagram below and answer the questions that follow.
(c) Study the diagram below and answer the questions that follow.
(i) What is the set up used for?
(a)(i) Define the first ionization energy of an element
(ii) Consider the following table and use it to answer te question that follows
| Element | Li | Be | b | C | N | O | F | Ne |
| Atomic number | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 |
| 1st I.E/kj mol\(^{-1}\) | 520 | 900 | 801 | 1086 | 1402 | 1314 | 1681 | 2081 |
Explain briefly why the first ionization energy of B is less than that of Be despite the fact that the atomic number of B is greater than that of Be.
(b) When Titanium chloride was electrolysed by passing 0.12 A current through the solution for 500 seconds, 0.015 g of titanium was deposited. What is the charge on the titanium ion?
[ IF= 96500 C, Ti= 48.0 ]
(c)(i) Aluminium can be obtained by the application of electrolysis. State the electrolyte which yields aluminium on electrolysis.
(ii) Name two major factors which would favour the siting of an aluminium smelter in a country.
(d)(i) Define the term paramagnetism.
(ii) Consider the following ions: 24\(^{Cr ^{2+}}\), 24\(^{Cr^{6+}}\)
(I) Deduce the number of unpaired electrons in each of the ions.
(II) State which of the ions will have a greater power of paramagnetism
(l) Give a reason for the answer stated in (d)(ii)(II)