Air boiled out of water as steam is richer in
(A) nitrogen and oxygen
(B) carbon(iv)oxide and oxygen
(C) noble gases and carbon(iv)oxide
(D) oxygen and noble gases
Which of the following is an example of a mixture?
(A) common salt
(D) washing soda
Calculate the percentage by mass of nitrogen in calcium trioxonitrate (V) [Ca=40, N=14, O=16]
The droplets of water observed around a bottle of milk taken out of the refrigerator is due to the fact that the
(A) water vapour in the air around the bottle gains some energy from the bottle
(B) temperature of the milk drops as it loses heat into the surroundings
(C) saturated vapour pressure of the milk is equal to the atmospheric pressure
(D) water vapour in the air around the bottle loses some of its energy to the bottle
The volume of a given gas is V cm3 at P mm Hg. What is the new volume of the gas if the pressure is reduced to half at constant temperature?
(A) 4V cm2
(B) 2V cm3
(C) v/2 cm2
(D) V cm3
Moving from left to right across a period, the general rise in the first ionization energy can be attributed to the
(A) decrease in nuclear charge
(B) increase in nuclear charge
(C) decrease in screening effect
(D) increase in screening effect
How many unpaired electron(s) are there in the
The stability of the noble gases is due to the fact that they
(A) have no electron in their outermost shells
(B) have duplet or octet electron configurations
(C) belong to group zero of the periodic table
(D) are volatile in nature
The maximum number of electrons in the L shell of an atom is
Elements in the same period in the periodic table have the same
(A) number of shells
(B) atomic number
(C) chemical properties
(D) physical properties
In the course of purifying water for town supply ,the water is passed through large settling tanks containing sodium aluminate (iii) to remove
(A) large particles
(C) fine particles
A noble gas with a high power of fog penetration used in aerodrome beacons is
Permanent hardness of water can be removed by
(B) adding slaked lime
(C) adding caustin soda
Substances employed as drying agents are usually
Calculate the solubility in mol dm-3 of 40g of cuSo4 [Cu = 64, S=32, O=16]
Coffee stains can best be removed by
(C) a solution of borax in water
(D) ammonia solution
Carbon (II) oxide is considered dangerous if inhaled mainly because it
(A) can cause injury to the nervous system
(B) competes with oxygen in the blood
(C) competes with carbon (IV) oxide in the blood
(D) can cause lung cancer
2018 Jamb Questions and Answers on Chemistry
The acid that is used to remove rust is
(C) trioxonitrate (V)
(D) tetraoxosulphate (VI)
Calculate the volume of 0.5 mol dm-3 H2SO4 that is neutrialized by 25cm3 of 0.1 mol dm-3 NaOH.
The colour of methyl orange in alkaline mediums is
Which of the following salts is slightly soluble in water?
6AgNO3(aq) + PH3(g) + 3H2O(l)->6Ag(s) + H3PO3(aq) + 6HNO(3aq) . In the reaction above, the reducing agent is
The IUPAC nomenclature of the compound LiAIH is
(A) lithium tetrahydridoaluminate (III)
(B) aluminium tetrahydrido lithium
(C) tetrahydrido lithium aluminate (III)
(D) lithium aluminium hydride
Iron can be protected from corrosion by coasting the surface with
What quantity of aluminium is deposited when a current of 10A is passed through a solution of an aluminium salt for 1930s?
[Al = 27, F = 96 500 C. mol-1]
In which of the following is the entropy change positive?
(A) thermal dissociation of ammonium chloride
(B) Reaction between an acid and a base
(C) addition of concentrated acid to water
(D) dissolution of sodium metal in water
The colour of methyl orange in alkaline mediums is
In the preparation of oxygen by heating KCIO in the presence of MnO2, only moderate heat is needed because the catalyst acts by
(A) lowering the pressure of the reaction
(B) increasing the surface area of the reactant
(C) increasing the rate of the reaction
(D) lowering the energy barrier of the reaction
To a solution of an unknown compound, a little dilute tetraoxosulphate (VI) acid was added with some freshly prepared iron (II) tetraoxosulphate (VI) solution. The brown ring observed after the addition of a stream of concentrated teraoxosulphate (VI) acid confirmed the presence of
Which of the following is used as a rocket fuel?
A constituent common to bronze and solder is
When iron is exposed to moist air, it gradually rusts. This is due to the formation of
(A) hydrated iron (III) oxide
(B) anhydrous iron (III) oxide
(C) anhydrous iron (II) oxide
(D) hydrated iron (II) oxide
A compound gives an orange-red colour to a non-luminous flame. This compound is likely to contain
Stainless steel is used for making
(C) coins and medals
(D) moving parts of clocks
The residual solids from the fractional distillation of petroleum are used as
(A) coatings for pipes
(B) raw materials for the cracking process
(C) fuel for driving tractors
(D) fuel for jet engines
Which of the following is used as fuel in miners lamp?
Which of the following organic compounds is very soluble in water?
Benzene reacts with hydrogen in the presence of nickel catalyst at 180oC to give
Which of the following is used to hasten the ripening of fruits?
The final products of the reaction between methane and chlorine in the presence of ultraviolet light are hydrogen chloride and
One of the major uses of alkanes is
(A) as domestic and industrial fuels
(B) in the hydrogenation of oils
(C) in the textile industries
(D) in the production of plastics.
The haloalkanes used in the dry-cleaning industries are
(A) trichloromethane and tetrachloromethane
(B) chloroethene and dichloroethane
(C) trichoroethene and tetrachloroethane
(D) chloroethane and dichloroethene
Two hydrocarbons X and Y were treated with bromine water. X decolorized the solution and Y did not. Which class of compound does Y belong?
The compound that is used as an anaesthetic is
when a few drops of water is added to a blue anhydrous cobalt (ii) chloride ,the colour changes to
the vulcanizers solution is prepared by dissolving rubber in
117.0 g of sodium chloride was dissolved in 1.0 dm3 of distilled water at 25oc .Determine the solubility in mol dm-3 of sodium chloride at that temperature[Na=23,Cl=35.5]
The uncovered raw food that is sold along major roads is likely to contain some amounts of
what is the PH of a 0.001 mol dm-3 solution of sodium hydroxide?
The basicity of CH3COOH is
1 2b 3c 4d 5b 6b 7a 8b 9b 10a 11c 12a 13c 14b
15b 16d 17b 18d 19b 20a 21c 22c 23d 24d 25b
26a 27c 28d 29d 30b 31d 32a 33b 34c 35a 36b.
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