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

melting does not break the metallic bond but boiling does

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

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

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

I, II and IV

I and II only

I and IV

Separation Of Mixtures And Purification Of Chemical Substances

View Answer

Question 2 Report

The removal of rust from iron by treatment with tetraoxosulphate (vi) acid is based on the

Hydrolysis of the iron

Reaction of acid with base

Oxidation of the rust

Dehydration of the iron

Acids, Bases And Salts

View Answer

Question 3 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)

Atomic Structure And Bonding

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Question 4 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 5 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 6 Report

$ \mathrm{Zn + 2HCl \rightarrow ZnCl_2 + H_2} $

What happens to zinc in the above reaction?

oxidized

a reactant

reduced

a metal

Answer Details

In the above reaction, zinc (Zn) reacts with hydrochloric acid (HCl) to form zinc chloride (ZnCl2) and hydrogen gas (H2). The chemical equation for the reaction is: Zn + 2HCl → ZnCl2 + H2 During the reaction, zinc atoms lose two electrons each and get oxidized to form positively charged zinc ions (Zn2+), as they react with the hydrogen ions (H+) from the hydrochloric acid to form zinc chloride. The hydrogen ions, on the other hand, gain an electron each and get reduced to form hydrogen gas molecules (H2). Therefore, in the given reaction, zinc is getting oxidized, as it loses electrons and forms a positively charged ion. Hence, the correct option is "oxidized."

Read lesson note on Oxidation And Reduction (JAMB)

Oxidation And Reduction

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Question 7 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 8 Report

Complete dehydrogenation of ethyne yields

benzene

methane

ethane

propane

Chemistry Of Carbon Compounds (Nigeria Only)

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Question 9 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 10 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

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.

View Answer

Question 11 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 12 Report

Which of the following conducts electricity

Sulphur

Graphite

Diamond

Red phosphorous

Answer Details

Graphite is the option that conducts electricity.

Read lesson note on Electrolysis (JAMB)

Electrolysis

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Question 13 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 14 Report

which of these compounds exhibits resonance

benzene

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 15 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 Of Carbon Compounds (Nigeria Only)

Chemistry, Industry And The Environment

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Question 16 Report

Chlorine is a common bleaching agent. This is not true with

wet litmus paper

printers ink

wet pawpaw leaf

most wet fabric dyes

Answer Details

Chlorine is not a common bleaching agent for wet litmus paper, wet pawpaw leaf, and most wet fabric dyes. It is commonly used as a bleaching agent for printer's ink.

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

Acids, Bases And Salts (Ghana Only)

View Answer

Question 17 Report

The oxidation number of oxygen in BaO2 is

-2

-4

-1

0

Answer Details

To determine the oxidation number of oxygen in BaO2, we can use the fact that the overall charge of a compound must be zero. Barium (Ba) is a Group 2 element and has an oxidation state of +2. The compound BaO2 has no net charge, so the sum of the oxidation states of all the atoms must be zero. Let x be the oxidation state of oxygen in BaO2. Therefore, we have: (+2) + 2(x) = 0 Solving for x, we get: x = -1 Therefore, the oxidation number of oxygen in BaO2 is -1.

Read lesson note on Oxidation And Reduction (JAMB)

Read lesson note on Redox Reactions (WAEC)

Oxidation And Reduction

Redox Reactions

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Question 18 Report

H2SO4 is used to remove rust on the surface of iron (picking) before electroplating. The type of reaction involved is

redox reaction

Neutralization

Double decomposition

Hydrolysis

Answer Details

The type of reaction involved when using H2SO4 to remove rust on the surface of iron is a redox reaction. This is because the sulfuric acid oxidizes the iron in the rust, converting it into iron(II) sulfate, while the acid itself is reduced to sulfur dioxide. The overall reaction can be written as follows: Fe2O3(s) + 3H2SO4(aq) → Fe2(SO4)3(aq) + 3H2O(l) In this reaction, the iron in Fe2O3 is oxidized from a +3 to a +2 oxidation state, while the sulfur in H2SO4 is reduced from a +6 to a +4 oxidation state. This transfer of electrons between the reactants is what defines a redox reaction.

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

Read lesson note on Redox Reactions (WAEC)

Kinetic Theory Of Matter And Gas Laws

Redox Reactions

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Question 19 Report

The reactions below represent neutralization reaction, in which of them is the value of ΔH highest?

CH

_{3}

CH

_{2}

COOH + KOH → CH

_{3}

CH

_{2}

COOK + H

_{2}

O

NH

_{4}

OH + HCL → NH

_{4}

+ H

_{2}

O

NaOH + HCL → NaCL + H

_{2}

O

CH

_{3}

COOH + NaOH → CH

_{3}

COONa + H

_{2}

O

Answer Details

The reaction with the highest ΔH (change in enthalpy) would be the reaction between HCL and NaOH, which forms NaCL and H2O. This is because the formation of water releases energy in the form of heat, which is reflected in the positive ΔH value for this reaction. When an acid and a base react, they neutralize each other and form a salt and water, with the release of heat being a sign of an exothermic reaction.

Read lesson note on Environmental Pollution (JAMB)

Environmental Pollution

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Question 20 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 21 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

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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Question 22 Report

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

copper

magnesium

silver

lead

Metals And Their Compounds

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Question 23 Report

An organic functional group which can likely decolorize ammoniacal silver nitrate is?

alkene

alkane

alkyne

alkanol

Answer Details

The organic functional group that can likely decolorize ammoniacal silver nitrate is an alkyne. When ammoniacal silver nitrate is added to a solution containing an alkyne functional group, a white or yellowish precipitate of silver acetylide is formed. Silver acetylide is a highly explosive compound and is sparingly soluble in water, causing it to appear as a white or yellowish solid precipitate. This reaction is used as a test to detect the presence of an alkyne functional group in an organic compound. In contrast, alkanes, alkenes, and alkanols do not react with ammoniacal silver nitrate, so they cannot decolorize it. Therefore, an organic functional group that can likely decolorize ammoniacal silver nitrate is an alkyne.

View Answer

Question 24 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

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 25 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 26 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 27 Report

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

Temperature of the system

degree of disorder of the system

number of molecule

Activation energy

Answer Details

The degree of disorder of the system increases as boiling water changes to steam. When water is boiled and changes to steam, the water molecules gain energy and become more disordered, which means that the molecules move more rapidly and the entropy of the system increases. The temperature of the system also increases during this process, but the degree of disorder is the factor that specifically increases as the water changes to steam. The number of molecules and activation energy remain constant during this phase transition.

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

Kinetic Theory Of Matter And Gas Laws

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Question 28 Report

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

HC≡CCH

_{2}

CH

_{3}

CH

_{2}

≡CH

_{2}

CH

_{3}

CH

_{3}

C≡CCH

_{3}

CH

_{3}

CH=CHCH

_{3}

Chemistry Of Carbon Compounds (Nigeria Only)

View Answer

Question 29 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)

Kinetic Theory Of Matter And Gas Laws

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Question 30 Report

Addition of charcoal to the filter bed of sand during water treatment for township supply is to?

prevent goiter

prevent tooth decay

remove odour

kill germs

Answer Details

The addition of charcoal to the filter bed of sand during water treatment for township supply is to remove odors and improve the taste of the water. Charcoal is a porous material that can adsorb impurities and chemicals from the water, such as dissolved organic matter that can contribute to unpleasant tastes and odors. This process helps to produce a better-quality drinking water that is free from unpleasant tastes and odors. It should be noted that while the addition of charcoal can help remove impurities, it does not kill germs or prevent tooth decay or goiter. Other water treatment methods, such as disinfection with chlorine or ultraviolet light, are required to kill harmful microorganisms and ensure the safety of the drinking water.

Read lesson note on Solubility (JAMB)

Solubility

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Question 31 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

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 32 Report

Which of the following is stable to heat

NaHCO3

( NH4 )2 SO4

Ag NH3

K2 CO3

Answer Details

Out of the given options, K2CO3 is stable to heat.

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

Non-metals And Their Compounds

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Question 33 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 34 Report

Mixing aqueos solution of barium hydroxide and sodium tetraoxocarbonate (iv) yields a white precipitate of

Barium oxide

Sodium tetraoxocarbonate

Sodium hydroxide

Barium tetraoxocarbonate

Answer Details

Mixing aqueous solutions of barium hydroxide and sodium tetraoxocarbonate (IV) would result in a chemical reaction that produces a white precipitate of barium tetraoxocarbonate (IV). The balanced chemical equation for this reaction is: Ba(OH)2(aq) + Na2CO3(aq) → BaCO3(s) + 2NaOH(aq) In the above equation, the barium hydroxide (Ba(OH)2) reacts with sodium tetraoxocarbonate (IV) (Na2CO3) to form barium tetraoxocarbonate (IV) (BaCO3), which is a white precipitate, and sodium hydroxide (NaOH). Therefore, the correct option is 4) Barium tetraoxocarbonate.

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

Acids, Bases And Salts

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Question 35 Report

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

C

_{3}

H

_{8}

C

_{2}

H

_{6}

C

_{4}

H

_{1} 0

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

View Answer

Question 36 Report

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

The equation above illustrates

precipitation

hydration

hydrolysis

neutralization

Acids, Bases And Salts (Ghana Only)

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Question 37 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?

CO

_{2}

and O

_{2}

N

_{2}

and CO

_{2}

CO

_{2}

, O

_{2}

and N

_{2}

O

_{2}

and N

_{2}

Separation Of Mixtures And Purification Of Chemical Substances

View Answer

Question 38 Report

An organic compound which liberate carbon(iv)oxide from trioxocarbonate(iv) solution is likely to be?

C

_{2}

H

_{5}

OH

C

_{3}

H

_{4}

C

_{6}

H

_{6}

CH

_{3}

COOH

Answer Details

The organic compound that liberates carbon(iv)oxide from trioxocarbonate(iv) solution is CH3COOH (acetic acid). When acetic acid is added to a solution of trioxocarbonate(iv) (carbonate) it reacts to form carbon(iv)oxide gas, water and a salt. The balanced chemical equation for the reaction is: 2CH3COOH + Na2CO3 → CO2 + 2H2O + 2NaCH3COO The carbon(iv)oxide gas is released as bubbles, causing the solution to fizz. Therefore, CH3COOH is the organic compound that liberates carbon(iv)oxide from trioxocarbonate(iv) solution.

View Answer

Question 39 Report

Calcium forms complexes with ammonia because

it is a transition metal

it is an s-block element

it has empty d-orbital

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 40 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}

Atomic Structure And Bonding

View Answer

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






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