The atom of an element X combines with aluminium (\(^{13}\)AI)?
- A. AIX 2
- B. AI 2X
- C. AI2X 2
- D. AI 2X 3
Elements which belong to the same group in the Periodic Table are characterized by
- A. difference of +1 in the oxidation numbers of successive members
- B. presence of the same number of outermost electrons in the respective atoms
- C. difference of 14 atomic mass units between successive members
- D. presence of the same number of electron shells in the respective atoms
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?
- A. P
- B. C
- C. R
- D. S
Given that the electronic configuration of an element X is 1s22s22p63s 23p4, it can be deduced that X
- A. belongs to group VI in the Periodic Table
- B. belongs to periodic Table
- C. contains 3 unpaired electrons in the ground state
- D. has atomic number 27
What is the mass number of an element if its atom contains 10 protons, 10 electrons and 12 neutrons?
- A. 32
- B. 22
- C. 20
- D. 10
Allotropes of an element differ in their
- A. physical properties
- B. chemical properties
- C. mass numbers
- D. electronic configuration
A plastic which cannot be softened by heat is described as
- A. thermosetting
- B. non-biodegradable
- C. thermoplastic
- D. malleable
Biotechnology is applied in the following except
- A. baking industry
- B. wine production
- C. production of antibiotics
- D. manufacture of soap
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
- A. 20 mol dm-3
- B. 0.40 mol dm-3
- C. 2.00 mol dm-3
- D. 5.00 mol dm -3
Which of the following on burning in air contributes to acid rain?
- A. Sulphur
- B. Magnesium
- C. Aluminium
- D. Zinc
When sodium hydroxide solution is added to a solution of zinc salt, the white precipitate formed re-dissolves in excess sodium hydroxide because
- A. sodium is more reactive than zinc
- B. sodium hydroxide is a strong alkali
- C. zinc hydroxide is amphoteric
- D. zinc hydroxide is unstable
A colourless, odourless liquid T, gives effervescence with sodium trioxocarbonate (IV) and a white precipitate with silver trioxonitrate (V) solution T is most probably
- A. sodium chloride solution
- B. barium chloride solution
- C. dilute trioxonitrate (V) acid
- D. dilute hydrochloric acid
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. K is a carbohydrate and L is a protein
- B. K is alkaline and L is acidic
- C. K is unsaturated and L is a reducing sugar
- D. K is a reducing agent and L is an amino acid
Which of the following needs to be hydrolyzed before it shows reducing property?
- A. Glucose
- B. Maltose
- C. Sucrose
- D. Fructose
Which of the following is correct about both compounds shown below? CH3CH 2CH2OH;CH 3
CH 2CH(OH)CH3
- A. They have identical physical properties
- B. They are structural isomers
- C. Their general molecular formula is the same
- D. They are oxidized to alkanones
C8H18 will undergo the following reactions except
- A. cracking
- B. combustion
- C. substitution
- D. addition
2 moles of hydrogen gas will react completely with one mole of….
- A. CH2=CHCl
- B. CH3-CH=CH2
- C. C6H5-CH3
- D. CH≡C-CH2-CH3
Which of the following procedures is suitable for identifying the food colouring added to a pastry sample?
- A. carry out some food tests
- B. examine the pastry sample under a microscope
- C. Do a chromatogram of the colouring extract
- D. .determine the molar mass of the colouring
Which of the following occurs when a solution of CuSO4 is electrolysed using copper electrodes?
- A. The cathode becomes coated with copper
- B. Both electrodes gain electrons
- C. The blue colour of the solution fades gradually
- D. The anode increases in mass
0.10 mol dm-3 NaCI conducts electricity better than 0.10 mol dm-3 CH3COOH because the solution of NaCI
- A. contains more ions
- B. is neutral to litmus
- C. has a lower molar mass
- D. has a higher pH
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 ?
- A. Fe 2+ (aq) + Cu(s) → Fe 3+ + Cu 2+ (aq)
- B. Fe 2+ (aq) + Cu(s) → Fe(s) + Cu2+ (aq)
- C. Fe (s) + Cu2+ (aq) → Fe2+(aq) + Cu2+ (aq)
- D. Fe(s) + Cu2+ → Fe2+(aq) + Cu(s)