Chemistry — 2000
WASSCE · 45 questions · Answers included
45 questions
The atoms of four elements are represented as 20Q, 16R, 10S and 8T Which of the elements would be unreactive?
Chlorine atom forms \(Cl^{-}\) by
An element Z has a combining power of 3. Which of the following formulae is correct of its compounds?
Electrovalent compounds are characterized by
The type of chemical bond that exists between potassium and oxygen in potassium oxide is
Which of the following contains co-ordinate covalent bond?
Electrostatic force of attraction between sodium ion and halide ion is greatest in
Which of the following non-metals reacts most readily with metals?
A radioactive solid is best stored
What is the shape of a molecule of CCI4?
What are the values of x and y in the following equation? \(^{234}_{90}\)Th → \(^y_x\)Pa + ß- particle
Which of the following increases as boiling water changes to steam?
9.60 g of a gas X occupies the same volume at 0.30 g of hydrogen under the same conditions. Calculate the molar mass of X [H = 1]
Which of the following gases is colourless, odourless and soluble in potassium hydroxide solution?
The gas evolved when dilute tetraoxosulphate (VI) acid reacts with sodium hydrogen trioxocarbonate (IV) is
If a solution has a pH of 2, it can be concluded that it
Which of the following salts is stable to heat?
Which of the following compounds dissolves in water to give an alkaline solution?
Which of the following salts is an acid salt?
What type of reaction is involved when wood shavings produce a brown gas with concentrated HNO3?
Chemical equilibrium is attained when
What is the effect of using vanadium (V) oxide as catalyst in the reaction represented by the following equation? 2SO2 + O2 ⇌ 2SO3; ∆H = - xKJmol-1
A finely divided form of a metal burns more readily in air than the rod form because the rod has
Which of the following will displace copper from a solution of copper (ll) salt?
What is the value of x in the following equation? Cr2O72- + 14H+ + xe- → 2Cr3+ + 7H2O
In which of the following is the oxidation number of sulphur equal to -2?
An iron nail placed in a solution copper (ll) tetraoxosulphate (VI) is soon covered with a deposit of copper. Which of the following equations represents the reactions ?
0.10 mol dm-3 NaCI conducts electricity better than 0.10 mol dm-3 CH3COOH because the solution of NaCI
Which of the following occurs when a solution of CuSO4 is electrolysed using copper electrodes?
Which of the following procedures is suitable for identifying the food colouring added to a pastry sample?
2 moles of hydrogen gas will react completely with one mole of....
C8H18 will undergo the following reactions except
Which of the following is correct about both compounds shown below? CH3CH 2CH2OH;CH 3 CH 2CH(OH)CH3
Which of the following needs to be hydrolyzed before it shows reducing property?
Two-organic substances are labelled K and L if K gave a blue-black colour with iodine solution and L gave a deep red precipitate with Million's reagent, it can be concluded that
A colourless, odourless liquid T, gives effervescence with sodium trioxocarbonate (IV) and a white precipitate with silver trioxonitrate (V) solution T is most probably
When sodium hydroxide solution is added to a solution of zinc salt, the white precipitate formed re-dissolves in excess sodium hydroxide because
Which of the following on burning in air contributes to acid rain?
If 20 cm3 of distilled water is added to 80 cm3 of 0.50 mol dm-3 hydrochloric acid, the concentration of the acid will change to
Biotechnology is applied in the following except
A plastic which cannot be softened by heat is described as
Allotropes of an element differ in their
What is the mass number of an element if its atom contains 10 protons, 10 electrons and 12 neutrons?
Given that the electronic configuration of an element X is 1s22s22p63s 23p4, it can be deduced that X
P,Q,R and S are metals in the same group in the Periodic Table but in periods 3,4, 5 and 6 respectively which of them loses electrons least readily?