JAMB UTME - Chemistry - 2022

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Question 2 Report

Electrons enter into orbitals in order of increasing energy as exemplified by?

1S

^{2}

2S

^{2}

2PX

^{2}

2py

^{2}

2pz

^{0}

3s

^{0}

1S

^{2}

2S

^{2}

2PX

^{2}

2py

^{1}

2pz

^{1}

3s

^{0}

1S

^{2}

2S

^{2}

2PX

^{1}

2py

^{1}

2pz

^{1}

3s

^{1}

1S

^{2}

2S

^{2}

2PX

^{2}

2py

^{2}

2pz

^{0}

3s

^{1}

View Answer

Question 3 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

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 4 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

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Question 5 Report

Which of the following is used as a moderator to control nuclear fission?

Lead

Heavy water

Iron

Chromium

Answer Details

Heavy water (D2O) is used as a moderator to control nuclear fission. A moderator is a substance that is used to slow down the neutrons produced in a nuclear reaction, making them more likely to be captured by the fuel nuclei and causing further fission. Heavy water is a type of water that contains a larger amount of the isotope deuterium (D) than regular water. Deuterium has an extra neutron compared to the more common hydrogen isotope, and this makes heavy water more effective at slowing down neutrons than regular water. Lead, iron, and chromium are not typically used as moderators in nuclear reactors. Lead can be used as a shield to absorb radiation, while iron and chromium are used in the construction of the reactor vessel and other components.

Read lesson note on Electrolysis (JAMB)

Electrolysis

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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

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

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

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 8 Report

A sample of gas with an initial volume of 2.5 dm3 is heated and then allowed to expand to 7.5 dm3 at constant at pressure. What is the ratio of the final temperature of the initial absolute temperature?

3:1

1:3

2:5

5:2

Answer Details

According to Charles's Law, the ratio of the initial and final temperatures is equal to the ratio of the initial and final volumes at constant pressure. The ratio of the final volume to the initial volume is: Vf / Vi = 7.5 dm3 / 2.5 dm3 = 3 Therefore, the ratio of the final temperature to the initial temperature is also 3: Tf / Ti = Vf / Vi = 3 So the answer is 3:1.

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

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Question 9 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

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 10 Report

Copper (II) tetraoxosulphate (IV) is widely used as

fertilizer

fungicide

Disinfectant

purifier

Answer Details

Copper (II) tetraoxosulphate (IV), also known as copper sulfate or CuSO4, is widely used as a fungicide and a disinfectant. As a fungicide, copper sulfate is effective in controlling fungal diseases in plants, including mildew, leaf spots, and blights. It is also used as a fungicide in swimming pools to prevent the growth of algae. As a disinfectant, copper sulfate is effective in killing bacteria and viruses. It is used in a variety of applications, including in the production of animal feed, as a preservative for wood, and in water treatment to kill bacteria and algae. While copper sulfate has been used as a fertilizer in the past, its use in this capacity has largely been replaced by other compounds. It is not commonly used as a purifier.

Read lesson note on Stoichiometry And Chemical Reactions (WAEC)

Read lesson note on Environmental Pollution (JAMB)

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

Stoichiometry And Chemical Reactions

Environmental Pollution

Periodic Chemistry (Ghana Only)

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Question 11 Report

Which of the following substances is not a homogeneous mixture?

filtered sea water

soft drinks

flood water

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 12 Report

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

magnetite

haematite

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 13 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

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

Electrolysis

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Question 14 Report

How many bonding pair are present in carbon(iv)oxide?

4

3

2

1

Answer Details

Carbon dioxide (CO2) has a linear molecular geometry, with two oxygen atoms bonded to the central carbon atom. Each bond between carbon and oxygen is a double bond, consisting of two pairs of electrons shared between the atoms. Therefore, there are two bonding pairs in each of the carbon-oxygen double bonds, giving a total of four bonding pairs in CO2. The answer is 4.

Read lesson note on Atomic Structure And Bonding (JAMB)

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Question 15 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

the silver chloride forms complexes in the sun

Oxidation And Reduction

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Question 16 Report

One of the active components of baking powder is

MgSO4

NaHCO3

CaSO4

NaCl

Answer Details

The active component of baking powder is sodium bicarbonate (NaHCO3). It is responsible for the leavening or rising of baked goods by releasing carbon dioxide gas when it reacts with an acid. Other ingredients in baking powder, such as monocalcium phosphate and sodium aluminum sulfate, provide the acid component for the reaction to occur. Magnesium sulfate (MgSO4) and calcium sulfate (CaSO4) are not typically used in baking powder, and sodium chloride (NaCl) is simply table salt and not an active ingredient in leavening.

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

Acids, Bases And Salts

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Question 17 Report

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

1-chloropropan-3-ol

3-chloropropan-1-ol

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)

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Question 18 Report

The IUPAC nomenclature of the structure is

3-chloro-3-methylbutane

2,2,-dichloro-3-methylbutane

3-methylchlorobutane

2-chloro-2-methylbutane

Answer Details

The IUPAC nomenclature of the structure is "2-chloro-2-methylbutane". The name is derived by first identifying the longest carbon chain, which in this case contains four carbon atoms (butane). The carbon chain is numbered from one end to the other, giving the substituents the lowest possible numbers. Starting from either end, we can see that the first carbon atom has a chlorine atom attached to it, which is represented by the prefix "chloro-". Moving along the chain, the second carbon atom has a methyl group attached to it, which is represented by the prefix "methyl-". Since the substituents are in the second position from each other, we use the prefix "di-" to indicate two substituents in this position. Finally, we use the suffix "-ane" to indicate that the molecule is an alkane. Therefore, the correct name for this molecule is "2-chloro-2-methylbutane".

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

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

Read lesson note on Chemistry, Industry And The Environment (WAEC)

Chemistry Of Carbon Compounds (Ghana Only)

Chemistry, Industry And The Environment

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Question 19 Report

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

thermodynamic

exothermic

isothermal

endothermic

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)

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Question 20 Report

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

valves

open-hearths

arcs

tuyeres

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 21 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\(^{3}\)?

30

40

20

50

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Question 22 Report

Which of the following will precipitate in dil. HCl

ZnS

Na2 S

Fe S

CuS

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 23 Report

A chemical widely used as a fertilizer is?

galena

bauxite

emerald

nitrochalk

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 24 Report

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

reacts with glycerol

purifies the soap, accelerates the decomposition of fat and oil

separates soap from glycerol

converts the fat acid to its sodium salt

Answer Details

The role that sodium chloride (NaCl) plays in soap preparation is to separate soap from glycerol. When fats or oils are hydrolyzed with an alkali, such as sodium hydroxide (NaOH), the result is a mixture of soap and glycerol. Adding NaCl to this mixture helps to induce the precipitation of the soap, allowing it to be separated from the glycerol. This process is known as "salting out" and is used to purify the soap and remove impurities. Sodium chloride does not react with glycerol or accelerate the decomposition of fat and oil. Also, it does not convert the fatty acid to its sodium salt as this conversion is done by the alkali (such as NaOH) during the saponification process.

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

Acids, Bases And Salts

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Question 25 Report

Which of the following compound is NOT the correct formed compound when the parent metal is heated in air?

Calcium oxide

Sodium oxide ( Na2O )

Copper (II) oxide (CuO)

tri-iron tetraoxide (Fe2O)

Answer Details

The compound that is NOT correctly formed when the parent metal is heated in air is: tri-iron tetraoxide (Fe2O). This is because the correct compound formed from the heating of iron in air is iron (III) oxide or Fe2O3. The formula for tri-iron tetraoxide is incorrect, as it implies that there are only three iron atoms in the compound when there should be four.

Read lesson note on Metals And Their Compounds (JAMB)

Metals And Their Compounds

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Question 26 Report

A colored gas that is known to be poisonous and can readily damage the mucous lining of the lungs is?

hydrogen sulphid

carbon(ii)oxide

chlorine

sulphur(iv)oxide

Answer Details

The colored gas that is known to be poisonous and can readily damage the mucous lining of the lungs is chlorine. Chlorine is a highly reactive chemical element that is used in the production of many everyday products, such as paper, textiles, and plastics. It is also used as a disinfectant in swimming pools and water treatment plants. Inhaling chlorine gas can cause severe respiratory problems, including coughing, chest pain, and difficulty breathing. Prolonged exposure to chlorine can cause lung damage, and in extreme cases, it can be fatal. Chlorine gas is also highly irritating to the eyes, skin, and mucous membranes. It is important to handle chlorine with caution and to use appropriate protective gear, such as gloves and respiratory masks, when working with it. Proper ventilation and monitoring of chlorine levels are also essential to prevent exposure to this toxic gas.

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

Read lesson note on Organic Compounds (JAMB)

Organic Compounds

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Question 27 Report

\(2\mathrm{H}_2 + \mathrm{O}_2 \rightarrow 2\mathrm{H}_2\mathrm{O}\)

From the equation above, calculate the volume of unreacted oxygen gas if a mixture of \(50\mathrm{cm}^3\) of hydroden and \(75\mathrm{cm}^3\) of oxygen are involved

85cm

^{3}

50cm

^{3}

125cm

^{3}

55cm

^{3}

Answer Details

The balanced chemical equation shows that 2 moles of hydrogen gas react with 1 mole of oxygen gas to produce 2 moles of water vapor. Therefore, the stoichiometric ratio of hydrogen to oxygen is 2:1. In this problem, there are 50cm3 of hydrogen gas and 75cm3 of oxygen gas. Since the gases are at the same temperature and pressure, their volumes are directly proportional to the number of moles of gas present. Using the stoichiometric ratio, we can calculate that the amount of oxygen gas required to react completely with 50cm3 of hydrogen gas is (1/2) * 50cm3 = 25cm3. Since there are 75cm3 of oxygen gas present, there must be (75cm3 - 25cm3) = 50cm3 of unreacted oxygen gas remaining. Therefore, the volume of unreacted oxygen gas is 50cm3. Answer: 50cm3

Read lesson note on Stoichiometry And Chemical Reactions (WAEC)

Stoichiometry And Chemical Reactions

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Question 28 Report

Alkanes are used mainly?

in the textile industry

in the hydrogenation of oils

as domestic and industrial fuels

as fine chemicals

Chemistry, Industry And The Environment

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Question 29 Report

Which of the following will act as both oxidizing agents and reducing agents?

H2 S

NH3

Cl2

SO2

Answer Details

The oxidizing and reducing properties of a substance depend on its ability to gain or lose electrons. A substance that can gain electrons acts as an oxidizing agent, while a substance that can lose electrons acts as a reducing agent. Among the given options, both Cl2 (chlorine gas) and SO2 (sulfur dioxide) can act as both oxidizing and reducing agents depending on the reaction conditions. - Cl2 can act as an oxidizing agent when it gains electrons to form Cl- ions, and it can act as a reducing agent when it loses electrons to form Cl+ ions. For example, in the reaction Cl2 + 2KBr → 2KCl + Br2, chlorine gas is acting as an oxidizing agent since it is gaining electrons from bromide ions to form bromine gas. However, in the reaction 2Cl- + Cl2 → 2Cl2-, chlorine gas is acting as a reducing agent since it is losing electrons to form chloride ions. - SO2 can act as an oxidizing agent when it gains electrons to form sulfite ions (SO32-), and it can act as a reducing agent when it loses electrons to form sulfur trioxide (SO3). For example, in the reaction SO2 + 2H2S → 3S + 2H2O, sulfur dioxide is acting as a reducing agent since it is losing electrons to form elemental sulfur. However, in the reaction 2SO32- + O2 → 2SO42-, sulfur dioxide is acting as an oxidizing agent since it is gaining electrons to form sulfate ions. H2S (hydrogen sulfide) and NH3 (ammonia) are not likely to act as both oxidizing and reducing agents under normal conditions. H2S tends to act as a reducing agent by donating electrons to oxidizing agents, while NH3 tends to act as a reducing agent by donating electrons to oxidizing agents or as a base by accepting protons.

Read lesson note on Chemical Bonds (Ghana Only) (WAEC)

Chemical Bonds (Ghana Only)

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Question 30 Report

Using the metal activity series, the metal that can liberate hydrogen gas from steam is?

iron

copper

tin

lead

Answer Details

The metal that can liberate hydrogen gas from steam is iron. The metal activity series is a list of metals in order of their reactivity, with the most reactive metals at the top and the least reactive metals at the bottom. When a metal is placed in a solution of steam (water vapor), the metal will react with the steam if it is more reactive than hydrogen. In this case, iron is more reactive than hydrogen, so it can displace hydrogen from the steam to form hydrogen gas. This reaction can be represented by the equation: Fe + H2O (steam) → FeO (iron oxide) + H2 (hydrogen gas) So, when steam is passed over iron, hydrogen gas is liberated and iron oxide is formed.

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Question 31 Report

The sub-atomic particles located in the nucleus of an atom are?

neutron and proton

proton and electron

proton and ions

neutron and electron

Answer Details

The sub-atomic particles located in the nucleus of an atom are neutron and proton. The nucleus is the dense core of an atom that contains most of its mass. Protons are positively charged particles found in the nucleus, and they determine the atomic number of the element. Neutrons are neutral particles found in the nucleus, and they help stabilize the nucleus by balancing the repulsive forces between the positively charged protons. Electrons, on the other hand, are negatively charged particles that are located outside the nucleus in energy levels or shells. They are attracted to the positively charged nucleus by electrostatic forces and are involved in chemical bonding between atoms. The number of protons in the nucleus determines the identity of the element, while the number of neutrons determines its isotopes. Isotopes of an element have the same number of protons but different numbers of neutrons in the nucleus. In summary, the two sub-atomic particles located in the nucleus of an atom are neutron and proton.

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Question 32 Report

If the volume of a given mass of a gas at 0ºc is \(29.5\text{cm}^3\). What will be the volume of the gas at 15ºc, given that the pressure remains constant.

31.6

62.2

32.7

31.1

View Answer

Question 33 Report

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

RCONHR

^{1}

RCONH

_{2}

RNH

_{2}

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.

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Question 34 Report

Complete dehydrogenation of ethyne yields

benzene

methane

ethane

propane

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Question 35 Report

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

Over-head cables

Duralumin

Container for caustic soda

Container for trioxonitrate (v) acid

Metals And Their Compounds

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Question 36 Report

What is the shape of a molecule of CCl4?

Pyramid

tetrahedral

Trigonal planar

linear

Answer Details

The shape of a molecule of CCl4 is tetrahedral.

Read lesson note on Atomic Structure And Bonding (JAMB)

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Question 37 Report

On the basis of the electrochemical series, which of these ions will show the greater tendency to be discharged at the cathode in an electrolytic cell

cu

^{2 +}

sn

^{2 +}

fe

^{2 +}

zn

^{2 +}

Answer Details

The electrochemical series is a list of metals and ions arranged in order of their decreasing tendency to lose or gain electrons, and thus, their ability to act as reducing or oxidizing agents. The higher the position of a metal or ion in the electrochemical series, the greater its tendency to lose electrons and undergo oxidation, while the lower its position, the greater its tendency to gain electrons and undergo reduction. In an electrolytic cell, the cathode is the electrode where reduction occurs, meaning that cations (positively charged ions) are attracted and gain electrons to form neutral atoms or molecules. Based on the electrochemical series, the ion with the higher position in the series will have a greater tendency to gain electrons and be discharged at the cathode, while the ion with the lower position will have a lower tendency and may not be discharged at all. Among the given options, the electrochemical series order is: Cu2+ > Sn2+ > Fe2+ > Zn2+ Therefore, Cu2+ has the highest tendency to be discharged at the cathode and undergo reduction, while Zn2+ has the lowest tendency. So, in an electrolytic cell, Cu2+ will be discharged at the cathode, while Zn2+ may not be discharged at all, depending on the conditions of the cell.

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Read lesson note on Redox Reactions (WAEC)

Electrolysis

Redox Reactions

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Question 38 Report

A certain volume of gas at 298k is heated such that its volume and pressure are now four times the original values. What is the new temperature?

18.6K

100.0K

298.0K

4768.0K

Answer Details

We can use the ideal gas law to solve this problem, which states that PV = nRT, where P is pressure, V is volume, n is the number of moles of gas, R is the gas constant, and T is temperature in kelvin. If the volume and pressure are both increased by a factor of 4, then the new volume V' and new pressure P' are given by: V' = 4V P' = 4P Substituting these values into the ideal gas law, we get: (4P)(4V) = nR(T') Simplifying this equation, we get: 16PV = nRT' Dividing both sides by PV, we get: 16 = nRT' / PV Since n, R, and P are constant, we can simplify this to: 16 = T' / T Solving for T', we get: T' = 16T Therefore, the new temperature is 16 times the original temperature. Substituting T = 298 K, we get: T' = 16 x 298 K = 4768 K So the correct answer is 4768.0K.

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