The function of sulphur during the vulcanization of rubber is to

form chains which bind rubber molecules together

act as a catalyst for the polymerization of rubber molecules

convert rubber from thermosetting to thermoplastic polymer

form chains which bind rubber molecules together

break down rubber polymer molecules

Which of the following increases as boiling water changes to steam?

degree of disorder of the system

Which of the following roles does sodium chloride play in preparation? It

purifies the soap, accelerates the decomposition of fat and oil

converts the fat acid to its sodium salt

JAMB UTME - Chemistry - 2022 | Green Bridge CBT

Question 1 Report

Which of the following constitutes a mixture? I. Petroleum II. Rubber latex III. Vulcanizer’s solution IV. Carbon (iv) sulphide

I, II and III Correct answer

I, II and IV

I and II only

I and IV

Answer Details

Read lesson note on Separation Of Mixtures And Purification Of Chemical Substances (JAMB)

Separation Of Mixtures And Purification Of Chemical Substances

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Question 2 Report

In order to electroplate spoon with silver, the arrangement of the electrolytic cell is?

the anode is a silver rod and the cathode is the spoon Correct answer

the anode is the spoon and the cathode is a silver rod

the electrolyte is silver trioxonitrate(v)( solution and the cathode is a silver rod.

the electrolyte is silver trioxonitrate(v) solution and the anode is the spoon

Answer Details

Read lesson note on Electrolysis (JAMB)

Electrolysis

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Question 3 Report

Calcium forms complexes with ammonia because

it is a transition metal

it is an s-block element

it has empty d-orbital Correct answer

it forms colourless compounds

Answer Details

The reason why calcium forms complexes with ammonia is that it has empty d-orbitals.

Read lesson note on Atomic Structure And Bonding (JAMB)

Atomic Structure And Bonding

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Question 4 Report

A sample of gas exerts a pressure of 8.2 atm when confined in a 2.93 dm3 container at 20c. The number of moles of gas in the sample is

1. 00 Correct answer

2.00

3.00

4.00

Answer Details

Read lesson note on Kinetic Theory Of Matter And Gas Laws (JAMB)

Kinetic Theory Of Matter And Gas Laws

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Question 5 Report

In the extraction of iron, hot air is introduced into the blast furnace through?

valves

open-hearths

arcs

tuyeres Correct answer

Answer Details

In the extraction of iron, hot air is introduced into the blast furnace through tuyeres. Tuyeres are nozzles that are located at the bottom of the blast furnace, and they are used to blow hot air into the furnace. The hot air helps to burn the coke (a fuel made from coal) which provides the heat needed to melt the iron ore. The air also helps to remove the waste gases that are produced during the reaction, allowing the iron to be extracted more efficiently.

Read lesson note on Chemical Equilibria (JAMB)

Chemical Equilibria

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Question 6 Report

A certain liquid has a high boiling point. It is viscous, non-toxic, and miscible with water to be hygroscopic; this liquid most likely to be

CH3CH2CH2CH2OH

CH3CH2CHOH3

CH3CH2CH2CH2OH3

CH3OHCHOH2OH Correct answer

Answer Details

The liquid is most likely to be option number 4: CH3OHCHOH2OH, which is also known as glycerol or glycerin. Glycerol has a high boiling point of 290°C, which is much higher than the boiling points of the other options. It is also a viscous liquid, which means it is thick and sticky. Glycerol is non-toxic, and it is often used in food, pharmaceuticals, and cosmetics. Furthermore, glycerol is miscible with water, which means that it can be easily mixed with water to form a homogeneous solution. It is also hygroscopic, which means that it can absorb water from the air. These properties make glycerol a useful substance in many applications, such as as a moisturizer in skincare products or as a humectant in food processing.

Read lesson note on Acids, Bases And Salts (JAMB)

Acids, Bases And Salts

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Question 7 Report

What volume of (dm$^{3}$) of water will be added to 10dm$^{3}$ of 2.0 mol/dm$^{3}$ HCL acid solution to give a final solution of 0.5 mol/dm$^{3}$?

40 Correct answer

Answer Details

View Answer

Question 8 Report

GAS	$ \mathrm{CO_2} $	$ \mathrm{N_2} $	$ \mathrm{O_2} $
% BY VOLUME	4	72	24

The above table shows the compositions of the atmosphere of planet X. Which of these gases are present in higher percentages on earth?

_{2}

and O

_{2}

_{2}

and CO

_{2}

_{2}

, O

_{2}

and N

_{2}

_{2}

and N

_{2}

Correct answer

Answer Details

Read lesson note on Separation Of Mixtures And Purification Of Chemical Substances (JAMB)

Separation Of Mixtures And Purification Of Chemical Substances

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Question 9 Report

which of these compounds exhibits resonance

benzene Correct answer

ethanol

propene

butyne

Answer Details

The compound that exhibits resonance is benzene.

Read lesson note on Chemistry Of Carbon Compounds (Nigeria Only) (WAEC)

Chemistry Of Carbon Compounds (Nigeria Only)

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Question 10 Report

Hard water is water with high concentrations of dissolved ions, in particular calcium and

magnesium ions Correct answer

nitrogen ions

phosporus ions

helium ions

Answer Details

Hard water is water that contains high amounts of dissolved minerals, specifically calcium and magnesium ions. These minerals come from the rocks and soil that the water flows through and can accumulate in the water as it travels to your home. When you use hard water, it can leave mineral deposits on your pipes, fixtures, and appliances, which can reduce their efficiency and lifespan. It can also make soap less effective and leave your skin feeling dry and itchy. Therefore, it is important to treat hard water if it is a problem in your area.

Read lesson note on Solubility Of Substances (Ghana Only) (WAEC)

Solubility Of Substances (Ghana Only)

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Question 11 Report

Addition of sodium chloride to water to form a solution would lead to?

increase in freezing point and increase the boiling point

increase in freezing point and decrease the boiling point

decrease in freezing point and decrease the boiling point

decrease in freezing point and increase the boiling point Correct answer

Answer Details

The addition of sodium chloride to water to form a solution would lead to a decrease in freezing point and an increase in boiling point. This effect is known as colligative properties, which depend on the concentration of solute particles in a solution. When sodium chloride dissolves in water, it breaks down into sodium ions and chloride ions. These ions occupy space between water molecules and interfere with the formation of ice crystals during freezing. As a result, the freezing point of the solution is lowered below that of pure water. This is why we use salt to de-ice roads and sidewalks during the winter season. Similarly, the presence of solute particles in a solution also raises the boiling point of the solution. The increased concentration of solute particles in the solution causes a decrease in the vapor pressure of the solvent (water), making it harder for the solvent molecules to escape into the gas phase. This means that more energy is required to bring the solution to its boiling point compared to pure water. In summary, the addition of sodium chloride to water forms a solution with lower freezing point and higher boiling point compared to pure water.

Read lesson note on Solubility Of Substances (Ghana Only) (WAEC)

Read lesson note on Solutions (WAEC)

Solubility Of Substances (Ghana Only)

Solutions

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Question 12 Report

An organic compound contains 69% carbon, 15.3% hydrogen and 30.7% oxygen. Calculate the the empirical formula [C=12, H = 1, O = 16]

_{4}

_{1} 2

_{3}

_{9}

_{4}

_{9}

_{3}

_{8}

O Correct answer

Answer Details

View Answer

Question 13 Report

Which of the following will precipitate in dil. HCl

ZnS

Na2 S

Fe S

CuS Correct answer

Answer Details

Among the given options, only CuS will precipitate in dilute HCl. CuS is insoluble in dilute HCl, and hence it will precipitate when added to dilute HCl. However, the other options will dissolve in dilute HCl, and hence they will not precipitate. ZnS will dissolve in dilute HCl to form ZnCl2 and H2S. Na2S will react with dilute HCl to produce H2S and NaCl. FeS will dissolve in dilute HCl to form FeCl2 and H2S. Therefore, the correct answer is (4) CuS.

Read lesson note on Acids, Bases And Salts (JAMB)

Acids, Bases And Salts

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Question 14 Report

Which of the following statement is TRUE of the complete hydrolysis of a glyceride by sodium hydroxide?

3 moles of NaOH are required for each mole of glyceride Correct answer

3 moles of glycerol are produced

only one mole of soap is formed

concentrated H2SO4 is essential for the completion of the reaction.

Answer Details

The statement that is TRUE of the complete hydrolysis of a glyceride by sodium hydroxide is: - 3 moles of NaOH are required for each mole of glyceride. During the hydrolysis of a glyceride (a triglyceride), the ester bonds between the fatty acid chains and glycerol are broken by the action of a strong base like sodium hydroxide. This results in the formation of glycerol and the corresponding salts of fatty acids, which are commonly known as "soaps." The reaction can be represented by the following equation: Triglyceride + 3 NaOH → 3 soap + glycerol As per the equation, 3 moles of NaOH are required to hydrolyze one mole of glyceride, and 3 moles of soap and one mole of glycerol are produced. The use of concentrated sulfuric acid (H2SO4) is not essential for the completion of the reaction, but it can be used as a catalyst to speed up the reaction.

Read lesson note on Chemistry Of Carbon Compounds (Nigeria Only) (WAEC)

Chemistry Of Carbon Compounds (Nigeria Only)

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Question 15 Report

In which of the following will hydrogen form ionic compound?

HCL

NaH Correct answer

_{3}

_{4}

Answer Details

Read lesson note on Chemical Combination (JAMB)

Read lesson note on Organic Compounds (JAMB)

Chemical Combination

Organic Compounds

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Question 16 Report

Which of the following substances is not a homogeneous mixture?

filtered sea water

soft drinks

flood water Correct answer

writing ink

Answer Details

The substance that is not a homogeneous mixture is flood water. Flood water is typically a mixture of various substances, such as sediment, dirt, debris, and organic matter, that have been carried along by the water. As such, flood water is usually a heterogeneous mixture, meaning that it does not have a uniform composition throughout. In contrast, filtered sea water, soft drinks, and writing ink are all examples of homogeneous mixtures, where the components are evenly distributed and the mixture has a uniform composition throughout.

Read lesson note on Separation Of Mixtures And Purification Of Chemical Substances (JAMB)

Separation Of Mixtures And Purification Of Chemical Substances

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Question 17 Report

30 cm3 of oxygen at 10 atmosphere pressure is placed in a 20 dm3 container. Calculate the new pressure if the temperature is kept constant.

6.7 atm

15.0 atm Correct answer

6.0 atm

66.0 atm

Answer Details

Given:

Initial pressure, 𝑃1=10P1=10 atmospheres

Initial volume, 𝑉1=30 cm3V1=30cm3

Final volume, 𝑉2=20 dm3V2=20dm3

First, convert all volumes to the same units. Since 1 dm3dm3 is 1000 cm3cm3:

𝑉2=20 dm3=20×1000 cm3=20000 cm3V2=20dm3=20×1000cm3=20000cm3

Now, using Boyle's Law:

𝑃1𝑉1=𝑃2𝑉2P1V1=P2V2

Substitute the known values into the equation:

10×30=𝑃2×2000010×30=P2×20000

300=𝑃2×20000300=P2×20000

Solve for 𝑃2P2:

𝑃2=30020000P2=20000300

𝑃2=0.015 atmospheresP2=0.015atmospheres

Therefore, the new pressure if the temperature is kept constant is:

0.015 atmospheres0.015atmospheres

Read lesson note on Kinetic Theory Of Matter And Gas Laws (JAMB)

Kinetic Theory Of Matter And Gas Laws

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Question 18 Report

The following non-metal form acidic oxides with oxygen except?

phosphorus

sulphur

carbon

chlorine

Correct answer

Answer Details

An acidic oxide is an oxide that reacts with water to form an acidic solution. Non-metals have a greater tendency to form acidic oxides than metals. Therefore, among the given options, the non-metal that does not form an acidic oxide with oxygen would be the one that does not react with water to form an acidic solution. Out of the given options, chlorine is the non-metal that does not form acidic oxides with oxygen. Chlorine reacts with oxygen to form a number of oxides such as chlorine monoxide (Cl2O), chlorine dioxide (ClO2), and chlorine trioxide (ClO3), but none of these oxides react with water to form an acidic solution. Instead, they react with water to form oxyacids or oxoacids such as hypochlorous acid (HClO), chlorous acid (HClO2), and chloric acid (HClO3), which are stronger acids than the oxides. Therefore, the correct answer is chlorine.

Read lesson note on Organic Compounds (JAMB)

Read lesson note on Non-metals And Their Compounds (JAMB)

Organic Compounds

Non-metals And Their Compounds

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Question 19 Report

There is a large temperature interval between the melting point and the boiling point of metal because:

metals have a very high melting point

metals conduct heat very rapidly

melting does not break the metallic bond but boiling does Correct answer

the crystal lattice of metal is easily broken

Answer Details

The correct answer is: "melting does not break the metallic bond but boiling does." The metallic bond is the force of attraction between metal atoms, which holds them together to form a solid. When a metal is heated, its temperature increases, and at a certain point, the energy provided by the heat is enough to overcome the metallic bond and cause the metal to melt. However, even in the liquid state, the metallic bond remains intact, which is why metals have a very high melting point. On the other hand, when the temperature is further increased, the energy provided by the heat becomes enough to break the metallic bond, and the metal atoms become completely detached from one another. This results in the metal boiling and turning into a gas. Because the metallic bond is much stronger than other types of intermolecular forces, such as van der Waals forces, it requires a lot of energy to break, resulting in a large temperature interval between the melting point and boiling point of metal.

Read lesson note on Water (JAMB)

Read lesson note on Structure Of The Atom (WAEC)

Water

Structure Of The Atom

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Question 20 Report

The dehydration of $ \mathrm{CH_3CH_2CH_2CH_2OH} $ will give?

HC≡CCH

_{2}

_{3}

_{2}

≡CH

_{2}

_{3}

_{3}

C≡CCH

_{3}

_{3}

CH=CHCH

_{3}

Correct answer

Answer Details

Read lesson note on Chemistry Of Carbon Compounds (Nigeria Only) (WAEC)

Chemistry Of Carbon Compounds (Nigeria Only)

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Question 21 Report

A quantity of air passed through a weighted amount of alkaline pyrogallol. An increase in the weight of the pyrogallol would result from the absorption of

nitrogen

neon

argon

oxygen Correct answer

Answer Details

When air is passed through alkaline pyrogallol, the oxygen in the air is absorbed by the pyrogallol, resulting in an increase in the weight of the pyrogallol. The other gases in air, namely nitrogen, neon, and argon, do not react with pyrogallol under these conditions. Therefore, the answer is oxygen.

Read lesson note on Air (JAMB)

Air

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Question 22 Report

Wrought iron is obtained by heating cast iron in a furnace with?

magnetite

haematite Correct answer

carbon(ii)oxide

calcium trioxosilicate(iv)

Answer Details

Wrought iron is a type of iron that is very malleable and ductile, meaning it can be easily shaped and formed into various objects. It is obtained by heating cast iron in a furnace with haematite, also known as iron(III) oxide. When cast iron is heated with haematite in a furnace, a chemical reaction takes place where the haematite reacts with the carbon in the cast iron to produce carbon dioxide gas. This reaction also produces molten iron, which is then further heated to remove any impurities like sulfur and phosphorus. This molten iron is then poured into molds to form ingots of wrought iron. Therefore, haematite is essential in the process of obtaining wrought iron from cast iron.

Read lesson note on Metals And Their Compounds (JAMB)

Metals And Their Compounds

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Question 23 Report

Complete dehydrogenation of ethyne yields

benzene

methane

ethane

propane Correct answer

Answer Details

Read lesson note on Chemistry Of Carbon Compounds (Nigeria Only) (WAEC)

Chemistry Of Carbon Compounds (Nigeria Only)

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Question 24 Report

$H^+ + OH^- \rightarrow H_2O$

The equation above illustrates

precipitation

hydration

hydrolysis

neutralization Correct answer

Answer Details

Read lesson note on Acids, Bases And Salts (Ghana Only) (WAEC)

Acids, Bases And Salts (Ghana Only)

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Question 25 Report

Ethene, when passed into concentrated H2SO4, is rapidly absorbed. The product is diluted with water and then warmed to produce

Ethanol Correct answer

diethyl ether

ethanal

diethyl sulphate

Answer Details

When ethene is passed into concentrated H2SO4, it undergoes electrophilic addition reaction to form ethyl hydrogen sulfate as the product. The reaction mixture is then diluted with water and warmed to produce ethanol as the main product. Therefore, the answer is ethanol.

View Answer

Question 26 Report

The IUPAC name for CICH2-CH2-CH2-OH is

1-chloropropan-3-ol

3-chloropropan-1-ol Correct answer

1 cholorpropano

3-chloropropanol

Answer Details

The IUPAC name for CICH2-CH2-CH2-OH is 3-chloropropan-1-ol. To name the compound using the IUPAC nomenclature system, we start by identifying the longest continuous chain of carbon atoms that contains the functional group (-OH). In this case, the longest chain contains three carbon atoms, so the root name is propane. Next, we identify the position of the substituent (-Cl) on the chain. The substituent is attached to the third carbon atom in the chain, so the name of the compound becomes 3-chloropropane. Finally, we add the suffix -ol to indicate that the compound contains an alcohol functional group (-OH), so the complete name of the compound is 3-chloropropan-1-ol. Therefore, the correct answer is 3-chloropropan-1-ol.

Read lesson note on Chemistry Of Carbon Compounds (Nigeria Only) (WAEC)

Chemistry Of Carbon Compounds (Nigeria Only)

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Question 27 Report

Which of the following does NOT contain aluminum as a component?

Over-head cables

Duralumin

Container for caustic soda Correct answer

Container for trioxonitrate (v) acid

Answer Details

Read lesson note on Metals And Their Compounds (JAMB)

Metals And Their Compounds

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Question 28 Report

Which of the following conducts electricity

Sulphur

Graphite Correct answer

Diamond

Red phosphorous

Answer Details

Graphite is the option that conducts electricity.

Read lesson note on Electrolysis (JAMB)

Electrolysis

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Question 29 Report

When heat is absorbed during a chemical reaction, the reaction is said to be

thermodynamic

exothermic

isothermal

endothermic Correct answer

Answer Details

When heat is absorbed during a chemical reaction, the reaction is said to be endothermic. Endothermic reactions are characterized by the absorption of heat energy from the surroundings. In other words, the reactants absorb energy from the environment, usually in the form of heat, to form the products. As a result, the temperature of the surroundings decreases, and the reaction feels cold to the touch. Endothermic reactions can be found in many natural processes, such as photosynthesis, melting of ice, and the evaporation of liquids. These processes require energy to occur, and they absorb heat from the surroundings to power the reaction.

Read lesson note on Kinetic Theory Of Matter And Gas Laws (JAMB)

Kinetic Theory Of Matter And Gas Laws

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Question 30 Report

An organic compound with fishy smell is likely to have a general formula?

RCONHR

^{1}

RCONH

_{2}

RNH

_{2}

Correct answer

RCOR

^{1}

Answer Details

The organic compound with a fishy smell is most likely to have the general formula RNH2, which represents a primary amine. Amines are organic compounds that contain a nitrogen atom bonded to one or more carbon atoms. Primary amines have one alkyl or aryl group and two hydrogen atoms bonded to the nitrogen atom. Some primary amines have a fishy smell, which is caused by the presence of volatile amines. These amines are small molecules that can easily evaporate and have a strong odor, similar to that of fish. Examples of compounds that have a fishy smell include trimethylamine, which is found in fish, and butylamine, which is used in the production of rubber and pharmaceuticals. In summary, the organic compound with a fishy smell is likely to have the general formula RNH2, which represents a primary amine.

View Answer

Question 31 Report

A metal which can be used as sacrificial anode for preventing corrosion of length of iron pipe is

copper

magnesium

silver Correct answer

lead

Answer Details

Read lesson note on Metals And Their Compounds (JAMB)

Metals And Their Compounds

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Question 32 Report

A chemical widely used as a fertilizer is?

galena

bauxite

emerald

nitrochalk Correct answer

Answer Details

The chemical widely used as a fertilizer is nitrochalk. Nitrochalk is a type of fertilizer that contains a mixture of ammonium nitrate and calcium carbonate. Ammonium nitrate provides the necessary nitrogen for plant growth, while calcium carbonate helps to balance the soil's pH level. This combination of nutrients helps to promote healthy plant growth and increase crop yields. Nitrochalk is commonly used in agriculture and gardening to fertilize crops such as corn, wheat, and soybeans, as well as fruits and vegetables.

Read lesson note on Acids, Bases And Salts (JAMB)

Acids, Bases And Salts

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Question 33 Report

The sulphide that is commonly used in coating electric fluorescent tubes is?

iron(ii)Sulphide

tin(ii)sulphide

Zinc Sulphide Correct answer

lead(iv) Sulphide

Answer Details

The sulphide commonly used in coating electric fluorescent tubes is Zinc Sulphide. Zinc Sulphide is a type of material that glows when it is exposed to ultraviolet light. When ultraviolet light is generated inside a fluorescent tube, it excites the Zinc Sulphide particles, causing them to emit visible light. This visible light is what we see as the bright light coming from the tube. So, Zinc Sulphide acts as a phosphor and helps in producing the bright light in fluorescent tubes.

Read lesson note on Acids, Bases And Salts (JAMB)

Acids, Bases And Salts

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Question 34 Report

$\mathrm{N_2O_4}$ ? $2\mathrm{NO_2}$ (? = -ve)

From the reaction above, which of these conditions would produce the highest equilibrium yield for $\mathrm{N_2O_4}$?

Low temperature and high pressure

Low temperature and low pressure Correct answer

high temperature and low pressure

high temperature and high pressure

Answer Details

The highest equilibrium yield of N2O4 would be produced at low temperature and low pressure. In a chemical reaction, the position of the equilibrium can be influenced by changing the temperature or pressure. A decrease in temperature or an increase in pressure favors the side of the reaction with the fewer moles of gas (in this case, N2O4). This means that, if the temperature is low and the pressure is low, there will be more N2O4 at equilibrium, as the reaction will shift to the right to counteract the reduction in the concentration of N2O4. So, low temperature and low pressure would produce the highest equilibrium yield of N2O4.

Read lesson note on Chemical Combination (JAMB)

Chemical Combination

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Question 35 Report

When marble is heated to 1473K, another whiter solid is obtained which reacts vigoriously with water to give an alkaline solution. The solution contains

NaOH

KOH

Mg(OH)2

Ca(OH)2 Correct answer

Answer Details

The white solid obtained when marble (calcium carbonate, CaCO3) is heated to 1473K is calcium oxide (CaO), also known as quicklime. When quicklime reacts vigorously with water, it forms calcium hydroxide (Ca(OH)2), which is an alkaline solution. Therefore, the solution obtained from the reaction of quicklime with water contains calcium hydroxide (Ca(OH)2).

Read lesson note on Periodic Chemistry (Ghana Only) (WAEC)

Periodic Chemistry (Ghana Only)

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Question 36 Report

An organic compound which decolorizes bromine water is likely to be?

_{3}

_{8}

Correct answer

_{2}

_{6}

_{4}

_{1} 0

C $_{2}$ H $_{4}$ $_{2}$ $_{4}$

Answer Details

View Answer

Question 37 Report

Silver chloride turns gray when exposed to sunlight because

the silver ion is reduced to silver

the silver io is oxidized to silver

silver is transition metal Correct answer

the silver chloride forms complexes in the sun

Answer Details

Read lesson note on Oxidation And Reduction (JAMB)

Oxidation And Reduction

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Question 38 Report

An organic compound decolourized acidified KMnO4 solution but failed to react with ammonical AgNO3 solution. The organic compound is likely?

a carboxylic acid

Alkane

Alkene

Alkyne Correct answer

Answer Details

The given information suggests that the organic compound is an unsaturated compound (because it decolorized the acidified KMnO4 solution), but it does not contain a functional group that reacts with ammonical AgNO3 solution. Therefore, the likely organic compound is an alkene or an alkyne. Carboxylic acids can also react with acidified KMnO4 solution, but they would also react with ammonical AgNO3 solution to form a silver carboxylate salt. Alkanes are saturated compounds and do not react with either reagent, so they would not decolorize the acidified KMnO4 solution. Therefore, based on the given information, the most likely option is either an alkene or an alkyne.

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Question 39 Report

2-methylprop-1-ene is a structural isomer of?

But-1-yne

2-methyl But-1-ene

3-methyl prop-1-yne

But-2-ene Correct answer

Answer Details

Read lesson note on Chemistry Of Carbon Compounds (Nigeria Only) (WAEC)

Chemistry Of Carbon Compounds (Nigeria Only)

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Question 40 Report

6g of Mg was to 100cm3 of 1 moldm3 H2 SO4 . What mass of Mg remained undissolved? (Mg = 24)

0.24g

2.4g

3.6g Correct answer

0.36g

Answer Details

The balanced chemical equation for the reaction between magnesium (Mg) and sulfuric acid (H2SO4) is: Mg + H2SO4 -> MgSO4 + H2 According to the equation, one mole of Mg reacts with one mole of H2SO4 to produce one mole of magnesium sulfate (MgSO4) and one mole of hydrogen gas (H2). Since the concentration of the sulfuric acid is 1 moldm3, this means that there is one mole of H2SO4 in every 1 liter (1000 cm3) of solution. To determine the amount of Mg that reacts with the H2SO4, we need to use stoichiometry. One mole of Mg reacts with one mole of H2SO4, so the amount of Mg that reacts with 1 moldm3 of H2SO4 is given by: 6g / 24g/mol = 0.25 mol Since the reaction is 1:1, this means that 0.25 mol of H2SO4 is consumed in the reaction. The volume of the solution is 100cm3 (0.1 dm3), so the amount of H2SO4 in the solution is: 1 mol/dm3 x 0.1 dm3 = 0.1 mol The amount of H2SO4 that remains after the reaction is: 0.1 mol - 0.25 mol = -0.15 mol This negative value means that all of the H2SO4 was consumed in the reaction, and there is excess Mg left over. The mass of Mg that remains undissolved is given by: 0.15 mol x 24g/mol = 3.6g Therefore, the correct answer is 3.6g.

Read lesson note on Kinetic Theory Of Matter And Gas Laws (JAMB)

Kinetic Theory Of Matter And Gas Laws

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GAS	\( \mathrm{CO_2} \)	\( \mathrm{N_2} \)	\( \mathrm{O_2} \)
% BY VOLUME	4	72	24






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