12.
Which of the following pairs of elements are isotopes?
- (A)
Q and R
- (B)
R and T
- (C)
Q and S
- (D)
S and T
Free CXC Chemistry Paper 1 January 2022 past paper from 2022. Includes a worked answer key. Open the PDF, take a timed test, and study with AI on Caribbean AI.
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CSEC Chemistry Paper 1 January 2022 - Free CXC Past Paper with Answers
Free CXC Chemistry Paper 1 January 2022 past paper from 2022. Includes a worked answer key. Open the PDF, take a timed test, and study with AI on Caribbean AI.
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One property of ionic compounds is that they
contain molecules
are solids and vaporize easily
usually dissolve in organic solvents
conduct electricity when molten or dissolved in water
Which of the following processes provide evidence of the particulate nature of matter? I. Diffusion II. Filtration III. Osmosis
I and II only
I and III only
II and III only
I, II and III
Sodium chloride has a high melting point because
sodium has a high melting point
chlorine is a powerful oxidizing agent
the crystals do not absorb heat readily
the ions are bound by strong electrostatic forces
Which of the following mixtures are arranged in order of INCREASING particle size?
Solutions, colloids, suspensions
Solutions, suspensions, colloids
Colloids, solutions, suspensions
Suspensions, colloids, solutions
Sulfuric acid is a stronger acid than etha- noic acid (acetic acid) in aqueous solution because sulfuric acid
is more corrosive than ethanoic acid
is more concentrated than ethanoic acid
ionizes to a greater extent than ethanoic acid
causes sugar to char whereas ethanoic acid does not
An atom has 20 electrons. When it ionizes, it has the same electronic configuration as
neon
argon
sodium
calcium
Which of the following elements does NOT form simple ions by gaining or losing electrons?
Carbon
Copper
Calcium
Chlorine
What mass of oxygen atoms contains the same number of moles as 112 g of sulfur atoms? [RAM: O=16; S=32]
0.56 g
5.60 g
56.00 g
560.00 g
Barium is below calcium in Group II of the periodic table. When BOTH metals react with water, the MAIN observed differences would be the rate of reaction and the
type of product
type of gas evolved
reaction with litmus
solubility of the product
A mixture of copper(II) oxide and copper(II) sulfate is BEST separated by
distilling the mixture
heating the mixture and condensing
shaking with excess water and then filtering
shaking with excess water followed by fractional distillation
Which of the following elements exhibits allotropy?
Silicon
Carbon
Uranium
Aluminium
Which of the following pairs of elements are isotopes?
Q and R
R and T
Q and S
S and T
Which of the following elements is an anion?
Q
R
S
T
The element Q is
oxygen
chlorine
nitrogen
sulfur
Ethanoic acid reacts with ethanol to form an ester and water. How many moles of ethanoic acid are required to produce 0.5 mol of ester?
0.05
0.5
1
2
Crystals of sodium chloride are BEST described as
ionic
metallic
molecular
macromolecular
Which of the following substances does NOT conduct electricity?
Lead
Copper
Ethanol
Ethanoic acid
Two solutions are to be mixed in order to demonstrate endothermic change. Which of the following techniques would be MOST appropriate?
Taking mass readings
Taking temperature readings
Monitoring the pH of the solutions
Carefully observing colour changes
A piece of metal is reacted with an acid to produce hydrogen gas. Which of the following steps should be employed in order to increase the rate of the reaction?
I. Increasing the temperature at which the reaction is carried out II. Subdividing the piece of metal III. Reducing the concentration of the acid
I and II only
I and III only
II and III only
I, II and III
Which of the following substances reacts with an acid, liberating a gas which turns lime water milky?
Methyl orange
Barium chloride
Calcium carbonate
Magnesium metal
Which of the following diagrams illustrates the course of an exothermic reaction?
Which of the substances above can be described as the oxide of a metal?
Alkali
Base
Salt
Acid
Which of the substances above supplies protons as the ONLY positive ions in aqueous solution?
Alkali
Base
Salt
Acid
If substances containing one mole of solute per dm³ are investigated, which substance should cause the bulb to glow BRIGHTEST?
Water
Ammonia
Sulfuric acid
Ethanoic acid
When a metal atom becomes an ion, it
gains electrons and is oxidized
gains electrons and is reduced
loses electrons and is reduced
loses electrons and is oxidized
Which of the following diagrams illustrates bonding in oxygen?
Which of the following is the correct formula for ammonium carbonate?
NH₄CO₃
NH₄(CO₃)₂
(NH₄)₂CO₃
(NH₄)₂(CO₃)₂
Which of the following compounds is soluble in cold water?
Lead sulfate
Lead nitrate
Lead chloride
Lead carbonate
When a concentrated solution of sodium chloride is electrolysed using carbon electrodes,
chlorine is liberated at the anode
sodium is liberated at the cathode
the solution at the anode is acidic
the solution at the cathode is acidic
Which of the following statements is true for the equation below?
Hydrogen is oxidized from 0 to +1.
Hydrogen is reduced from +2 to 0.
Mg is oxidized from 0 to +2
Mg is reduced from +2 to 0.
The experiment above shows that magnesium oxide is
insoluble
neutral
acidic
basic
Which of the following substances is an important constituent of chlorophyll?
Iron
Copper
Calcium
Magnesium
Sulfur is used in which of the following processes?
I. Vulcanization of rubber II. Extraction of iron from iron ore III. Manufacture of explosives
I and II only
I and III only
II and III only
I, II and III
Potassium is a metal. From this information ONLY, it may be deduced that potassium
is soft
is very reactive
has a low melting point
is a good conductor of electricity
Which of the following observations is expected when aqueous silver nitrate is added to aqueous potassium chloride?
A pungent gas is evolved.
A blue precipitate appears.
A white precipitate appears.
A brown precipitate appears.
Which of the following metals will react MOST vigorously with dilute acid?
Copper
Iron
Lead
Zinc
Which of the following statements explains why, over time, aluminium products do NOT deteriorate in air as do iron products?
Aluminium is lower than iron in the activity series, therefore it reacts less readily with air than iron.
Aluminium is higher up in the activity series than iron, therefore it is more resistant to corrosion than iron.
Both metals form oxide coats but the aluminium oxide prevents further reaction while the iron oxide does not.
Both metals form hydroxide coats but the aluminium hydroxide prevents further reaction while the iron hydroxide does not.
Which of the following procedures can be used to identify ammonia gas?
Passing the gas through lime water
Placing a burning splint in a jar of the gas
Placing a glowing splint in a jar of the gas
Placing moist red and blue litmus paper in a jar of the gas
Ammonia may be produced in the laboratory by heating a mixture of ammonium chloride and
ammonium sulfate
calcium hydroxide
calcium chloride
copper
Items 40 and 41 refer to the extraction of aluminium from bauxite.
Cryolite is used
to lower the melting point of the electrolyte
as a source of additional ions
to protect the carbon anode
as the electrolyte
The carbon anode tends to
react with the cryolite
be oxidized by oxygen
dissolve in the electrolyte
be oxidized by fluorine from cryolite
Which of the following aqueous solutions will produce a yellow precipitate with aqueous potassium iodide?
Lead nitrate
Zinc sulfate
Calcium chloride
Sodium carbonate
Which of the following is/are true of non metals? I. They are reducing agents. II. They are capable of replacing hydrogen in acids to form salts. III. They are generally poor conductors of electricity.
III only
I and II only
I and III only
I, II and III
Hexane is an alkane with six carbon atoms per molecule. Which of the following is the formula for hexane?
Item 45 refers to the following structures of two organic compounds, I and II, whose molecular formula is .
Compound I H H H | | | H-C-C-C-H | | | H OH H
Compound II H H H | | | H-C-C-C-OH | | | H H H
Compounds I and II are known as the
isomers of
isotopes of
condensed formulae of
molecular formulae of
Which of the following features is NOT true of all homologous series of compounds?
the same functional group
the same general formula
similar chemical properties
the same empirical formula
Item 47 refers to the following equation. H H H 1 1 H-C-C=C-C-H + Br₂ → X 1 H
What is the correct structural formula for X?
Item 48 refers to the fully displayed structural formulae of Compounds Q, R and S shown below,
Which of the following correctly identifies the homologous series to which each compound belongs?
Ester / Acid / Alcohol
Acid / Alcohol / Ester
Alcohol / Ester / Acid
Acid / Ester / Alcohol
An organic substance, when reacted with bromine water, decolourizes it immediately. The substance is MOST likely an
alcohol
alkane
alkene
ester
Which of the following is the fully displayed structural formula of 2-bromobutane?
When a hydrocarbon molecule is cracked, which of the following smaller molecules are produced? I. An alkane II. An alkene III. An alcohol
I and II only
I and III only
II and III only
I, II and III
A polyamide is formed by a condensation reaction between a molecule containing
at least one -COOH group and another containing at least one -NH, group
at least one -OH group and another containing at least one -COOH group
at least one -OH group and another containing at least one -NH, group
two -OH groups and another containing two -COOH groups
Which of the following molecular formulae represents the alcohol whose boiling point is 160 °C?
CH(CH3)2OH
CH3(CH2)3OH
CH3CH(CH3)OH
CH3(CH2)5OH
Which reaction involves the boiling of a fat or oil with aqueous sodium hydroxide (caustic soda)?
Hydrolysis
Dehydration
Saponification
Esterification
The MAJOR natural source of alkenes is
petroleum
natural gas
the atmosphere
the earth's crust
Which of the following reactions occurs between propene and bromine?
Addition
Substitution
Precipitation
Condensation
Which of the following compounds can decolourize potassium manganate(VII)?
Which of the following substances is NOT a polymer?
Nylon
Protein
Fructose
Cellulose
Soapless detergents are
made from fats
all biodegradable
inorganic materials
not affected by hard water
The fermentation of sugars, using glucose as the substrate, can be represented by the equation