NECO Chemistry Questions and Answers 2022/2023 (Essay and Objectives)

NECO Chemistry Questions and Answers 2022/2023 (Essay and Objectives)

chemistry

NECO Chemistry Questions and Answers 2022. I will be teaching you past Chemistry objectives and theory repeated questions for free of charge in this post. You will also know how NECO Chemistry questions are structured and how to answer them.NECO Accounting Questions and Answers 2022/2023 (Essay and Objectives)

The National Examinations Council (NECO) is an examination body in Nigeria who’s role is to conduct the Senior Secondary Certificate Examination and the General Certificate in Education in June/July and December/January respectively.neco-chemistry-questions-and-answers/

NECO Chemistry Objectives and Essay Answers 2022(Expo)

The 2022 NECO Chemistry expo will be posted here during the NECO Chemistry examination. Keep checking and refreshing this page for the answers.

NECO 2022 Chemistry Answers Loading.

EBAAAAAACC: 1-10

BCBCACADCA: 11-20

AACBDDAACD: 21-30

CCACCACCDE: 31-40

EDCCDDBDAC: 41-50

CBACCDCBCD: 51-60

(1ai)

(i) KAl(SO₄)₂. 12H₂O

(ii) Na₂SO₄

(1aii)

Number of moles of sodium reascted = reacting mass/molar mass

= 3.6/23

= 0.1565moles

Number of moles of oxygen reacted = (1/4) x Number of sodium

= 1/4 x (3.6/23)

= 0.03913

Reacting mass of oxygen = Number of moles x molar mass

= 0.03913 x (16×2)

= 1.252grams

(1bi)

Air in gaseous form is first passed through caustic soda to remove CO₂. It is compressed and cooled until ut becomes a liquid at -200°C. It is then led to a fractionating column. On distillation, Nitrogen which has a lowet boiling point of -196°C is evolced first leaving behind Oxygen in liquid form. Further heating converts the liquid to a gas at -183°C.

(1bii)

(i) It is used for combustion

(ii) It is used for artificial respiration

(1biii)

This is because room temperature is warmer

(1biv)

(i) Methyl orange

(ii) Phenophthalein

(1ci)

An ion can be defined as an atom or molecule which has a net electric charge as a result of the loss or gain of one or more electrons.

(1cii)

HCl gas doesn’t contain ions

(1cii)

(i) Noble gases: Neon, Helium

(ii) Halogens: Iodine, Fluorine

(iii) Alkaline earth metals: Calcium, Magnesium

(1civ)

Halogens attain stable octet configuration by accepting an electron from donors Group I elements.

(1di)

A sol is a colloid where solid particles are dispersed in liquid medium.

(1dii)

Jelly

(1diii)

(i) Acid-base titrations are used to know the percentage purity of a substance

(ii) Acid-base titrations are crucial to know the number of water molecules in a hydrate.

(2ai)

A molar solution of a compound contains one mole or the molar mass of the compound in one dm³ of the solution.

(2aii)

(i) Identification of gases

(ii) Identification of acidic and metallic radicals

(2aiii)

(i) Purification of bauxite

(ii) Electrolysis of alumina

(2bii)

This is because of the presence of copper which is a transition metal

(2bii)

(i) Methanamide is a liquid while the rest amides are crystalline solids

(ii) Melting points and boiling points of aides are much higher than expected.

(2ci)

(i) Heavy chemicals are produced in very large quantities in industries While fine chemicals are produced in small quantities for specific purposes

(ii) Heavy chemicals are in a crude state while fine chemicals are purified.

(2cii)

(i) Million’s reagent

(ii) Feeling’s solution

(2ciii)

Graham’s law of diffusion states that at a constant temperature and pressure the rate of diffusion of a gas is inversely proportional to the square root of its density.

(2civ)

RO₂/RCH₄ = √(MCH₄/MO₂)

5/(200/t) = √[(12+4)/(16×2)]

5t/200 = √16/32

t/40 = 1/√2

t = 40/√2

t = (40/√2) × (√2/√2)

t = 20√2 seconds

Time taken = 28.28 seconds

5ai)

(i)Chlorofluorocarbons

(ii) Hydrofluorocarbon

(5aii)

I – C₂H₂OH + H₂SO₄ —>C₂H₅HSO₄ + H₂O

II – C₂H₅HSO₄ —> C₂H₄ +H₂SO₄

(5aiii)

(i) They incompletely filled d-orbitals

(ii) They exhibit variable oxidation state

(5bi)

(i) It is used in making aeroplane parts due to its tensile strength

(ii) It is used in making window frames because it cannot be easily oxidised

(5bii)

A white precipitate is formed with evolution of brown gas

(5biii)

(i) Hydrogen bond

(ii) Covalent bond

(5ci)

(i) Oxidation

(ii) Electrolysis

(5cii)

(i)Temperature

(ii)Concentration

(5ciii)

H₂SO₄ + 2NaOH —> Na₂SO₄ +2H₂O

CaVa/CbVb = Na/NB

Va = CbVbna/Can

Va = 0.1×25×1/0.5×2

Va = 2.5cm³

°°°°°°°°°°°°°°°°°°°°°°

(6ai)

Rate of a chemical reaction is defined as the number of moles of reactant converted or product formed per unit time.

(6aii)

Mass of CaCO3 = 3g

Molar mass of CaCO3= 100g/mol

No. of moles = 3/100 = 0.03

Time = 2×60 = 120s

Rate of reaction = No. of moles/Time

= 0.03/120 = 2.5 × 10-⁴

(6aiii)

(i) They are more resistant to corrosion

(ii) They are more durable

(iii) They have lower melting point

(6aiv)

2Pb(NO₃)₂ —> 2PbO + 4NO₂ +O₂

(6bi)

I =Hard water=

(i)It has better taste than soft water

(ii) It can be supplied in lead pipes as it does not dissolve lead

II =Soft water=

(i) It does not deposit scale in boilers and fur in kettles

(ii) It does not waste soap

(6bii)

I – CO

II – SO₂

(6biii)

I – Hardness

II – Lustre appearance

III – Conductivity

IV – Ability to absorb

(6c)

4.3/2.12 = 142+18x/142

2.12(142+18x)/2.12 = 4.3*142/2.12

142+18x = 288

18x = 288-142

x = 146/18

x = 8

——————————————————————————————————————-

The following NECO Chemistry questions are questions to expect in the 2022 NECO examination.

1.The least amount of energy needed for effective collisions between reacting particles is known

A) Activation energy

B) Bond energy

C) Kinetic energy

D) Potential energy

2.The bond formed between H2OH2O and H+H+ to form the hydroxonium H3O+H3O+ is

A) Dative

B) Covalent

C) Electrovalent

D) Ionic

3.An element XX forms the following oxides X2O,XOX2O,XO and XO2.XO2. This phenomenon illustrates the law of ________.

A) Conservation of mass

B) Definite proportion

C) Mass action

D) Multiple proportion

4.. How many moles of oxygen would contain 1.204×10241.204×1024 molecules?

NB: Avogadro’s constant (NA) =6.02×1023=6.02×1023

A) 1

B) 2

C) 3

D) 4

5.One of the following statements about solids is correct?

A) Solid particles are less orderly than those of a liquid

B) Solid have lower densities than liquids

C) Solid particles have greater kinetic energies than those of liquids

D) Solid particles cannot be easily compressed

6.One of the following apparatus can be used to measure a specific volume of a liquid accurately?

A) Beaker

B) Conical flask

C) Measuring cyclinder

D) Pipette

7.The general gas equation PVT=KPVT=K is a combination of

A) Boyle’s and Charles’ laws

B) Boyle’s and Graham’s laws

C) Charles’ and Graham’s laws

D) Dalton’s and Graham’s laws

8.The spreading of the scent of a flower in a garden is an example of?

A) Brownian motion

B) Diffusion

C) Osmosis

D) Tynadal effect

9.Propane and carbon (IV) oxide diffuse at the same rate because [H = 1.00, C = 12.0, O = 16.0]

Options

A) They are both gases

B) Their molecules contain carbon

C) They have the same relative molecular mass

D) Both are denser than air

1O. The energy which accompanies the addition of an electron to an isolated gaseous atom is

A) Atomization

B) Electronegativity

C) Electron affinity

D) Ionization

11.A sample of hard water has some calcium sulphate and calcium hydrogen carbonate. The total hardness may therefore be eliminated by

A)boiling the water

B)adding excess calcium hydroxide

C)adding a calculated amount of calcium hydroxide

D)adding sodium carbonate

E)adding magnesium hydroxide

12.During the electrolysis of copper II sulphate between platinum electrodes, if litmus solution is added to the anode compartment,

(a)the litmus turns blue but no gas is evolved

(b)the litmus turns blue and oxygen is evolved

(c)the litmus turns blue and hydrogen is evolved

(d)the litmus turns red and oxygen is evolved

(e)the litmus turns red and then becomes colourless

13.The reaction between an organic acid and an alcohol in the presence of an acid catalyst is referred to as;

(a)saponification

(b)dehydration

(c)esterification

(d)hydrolysis

(e)hydration

14.The IUPAC names of the compounds CH3COOH and CH2=CH2 are respectively;

(a)acetic acid and ethane

(b)ethanoic acid and ethene

(c)methanoic acid and ethylene

(d)ethanol and ethene

(e)acetic acid and ethylene

15.If 30cm3 of oxygen diffuses through a porous pot in 7 seconds, how long will it take 60cm3 of chlorine to diffuse through the same pot, if the vapour densities of oxygen and chlorine are 16 and 36 respectively?

a)9.3 sec

b)14 sec

c)21 sec

d)28 sec

e)30.3 sec

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

a)thermodynamic

b)exothermic

c)isothermal

d)endothermic

e)thermostatic

17.When large hydrocarbon molecules are heated at high temperature in the presence of a catalyst to give smaller molecules, the process is known as

a)disintegration

b)polymerization

c)cracking

d)degradation

e)distillation

18.The pH of four solutions W, X, Y, Z are 4, 6, 8, 10 respectively, therefore

a)none of these solutions is acidic

b)the pH of Y is made more acidic by addition of distilled water

c)Z is the most acidic solution

d)W is the most acidic solution

e)X is neutral

19.When each of the nitrates of Potassium, Magnesium and iron is heated,

a)all the nitrates decompose to their oxides

b)the nitrate of magnesium gives the nitrite and oxygen

c)the nitrates of iron magnesium and iron give the oxides

d)the nitrate of iron gives the nitrite and oxygen

e)the nitrate of the magnesium is not decomposed

2O. Which of the following metals cannot replace hydrogen from water or steam?

a)Sodium

b)Magnesium

c)Iron

d)Calcium

e)Copper

21.small quantity of solid ammonium chloride (NH4Cl) was heated gently in a test tube, the solid gradually disappears to produce two gases. Later, a white cloudy deposit was observed on the cooler part of the test tube. The ammonium chloride is said to have undergone

a)distillation

b)sublimation

c)precipitation

d)evaporation

e)decomposition

22.Elements P, Q, R, S have 6, 11, 15, 17 electrons respectively, therefore,

a)P will form an electrovalent bond with R

b)Q will form a covalent bond with S

c)R will form an electrovalent bond with S

d)Q will form an electrovalent bond with S

e)Q will form a covalent bond with R

23.An element X forms the following compounds with chlorine; XCl4, XCl3, XCl2. This shows the

a)law of multiple proportions

b)law of chemical proportions

c)law of simple proportions

d)law of conservation of mass

e)law of definite proportions

24.The oxidation state of chlorine in potassium chlorate is

a)+1

b)+2

c)+3

d)+5

e)+7

25.When air which contains the gases Oxygen, nitrogen, carbondioxide, water vapour and the rare gases, is passed through alkaline pyrogallol and then over quicklime, the only gases remaining are;

a)nitrogen and carbondioxide

b)the rare gases

c)nitrogen and oxygen

d)nitrogen and the rare gases

e)nitrogen, carbondioxide and the rare

26.One of the following statements  isn’t  correct?

a)The average kinetic energy of a gas is directly proportional to its temperature

b)At constant tempearture, the volume of a gas increases as the pressure increases

c)The pressure of a gas is inversely proportional to its volume

d)The temperature of a gas is directly proportional to its volume

e)The collisions of molecules with each other are inelastic

27.Zinc Oxide is a

a)Basic Oxide

b)Acidic Oxide

c)Amphoteric Oxide

d)Neutral Oxide

e)Reactive Oxide

28.When sodium chloride and metallic sodium are each dissolved in water

a)both processes are exothermic

b)both processes are endothermic

c)the dissolution of metallic sodium is endothermic

d)the dissolution of metallic sodium is exothermic

e)the dissolution of sodium chloride is explosive

29.The periodic classification of elements is an arrangement of the elements in order of their

a)Atomic Weights

b)Isotopic Weights

c)Molecular Weights

d)Atomic Numbers

e)Atomic Masses

3O. In the chemical reaction between sodium hydroxide and sulphuric acid solutions, what volume of 0.5 molar sodium hydroxide would exactly neutralise 10cm3 of 1.25 molar sulphuric acid?

a)5cm3

b)10cm3

c)20cm3

d)25cm3

e)50cm3

NECO Chemistry Exam 2022 Practice Test Questions (Paper 2)

Concerning this NECO Chemistry Questions And Answers 2022, don’t be concerned. To access the 2022 NECO Chemistry Questions And Answers for this year, simply keep refreshing this page. Within a few minutes, it will be placed here.

Advice or Passing the NECO Chemistry Exams in 2022

You can ace the 2022 NECO Chemistry exam with the help of the recommendations below.

Set a goal and work toward achieving it

I am confident that you have made the decision to pass NECO Chemistry 2022. Setting goals is the next thing you should do.

I will get an A in Neco Chemistry in 2022, you have promised yourself, but that’s not all. You must prepare for Questions And Answers 2022. All you need to do is to keep on refreshing this page for the 2022 NECO Chemistry Questions And Answers for this year. It will be posted here in few minutes.

Tips on How to Pass 2022 NECO Chemistry Examinations

The following guidelines will help you pass the 2022 NECO Chemistry examination with flying colours.

Have a Target and Work Towards Actualizing it

You have decided to pass NECO Chemistry 2022 and I am sure of that. Now, the next thing you should do is set targets.

You must establish a plan for how to implement it. To attain your goals, make a master strategy and timeframe.

Get the suggested chemistry textbook for the 2022 NECO exam.

NECO typically suggests literature for the test. In contrast, you are free to use any reputable Chemistry textbook to study for the NECO 2022 exam, with the exception of NECO Literature in English, which mandates the usage of specific novels.

Some texts are more challenging to comprehend. Get a textbook that will clarify any things you are having trouble understanding so that your life will be better.

Do not skim over the chemistry examples and exercises in the text:

While reading textbooks, many applicants enjoy skipping exercises and even examples. In reality

when studying textbooks, enjoy skipping exercises and even examples. We even have the question, “Can I read my notebook and pass NECO Chemistry 2022?” because we love notebooks so much. Don’t be afraid to try the chemistry exercises. Take on the obstacles.