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NECO Chemistry Practical Questions and Answers 2023/2024 (Complete Solution)

NECO Chemistry Practical 2023. Many NECO candidates find it difficult to answer the NECO Practical Chemistry Alternative A and B correctly due to not understanding the questions. I will show you the best way to answer the 2023 NECO Chemistry Practical questions and make a good grade in your Chemistry examination.

It is pertinent you understand the NECO Chemistry Practical making scheme before attempting any questions so as to present your answers in such a way that it will look attractive to the examiner to earn you big marks.

Bear in mind that every single procedure is awarded marks. So, ensure you do not skip any step while reporting and presenting your practical results.

The Chemistry Practical question paper will consist of two sections and general Chemistry questions namely:

  1. Quantitative Analysis
  2. Qualitative Analysis

These involve titration and test of ions. You will be expected to carry out an experiment and report your inference and observation. What you will see will not be far from the NECO Chemistry Specimen given to your school.

Note: Your titration endpoint will be given to you by your Chemistry teacher. It is not the same for every school but within a range.

Do not use the endpoint here. It may vary from your center endpoint but you can follow the calculation procedures.

See:

NECO Practical Chemistry Questions and Answers (Expo)

Note: The 2023 NECO Chemistry Practical answers will be posted here today 13th July during the NECO Practical Chemistry exam. Keep checking and reloading this page to know when the answers are posted. Do not forget to reload this page in order to see the answers.

NECO Practical Chemistry Answers 2023 Loading…

Today’s Chemistry Practical Answers:

For question 1

Use your school’s endpoint (average titre value). Ours is 21.20cm³. Wherever you see our endpoint (21.20cm³), put ur school’s own. Your Chemistry teacher should have given you people before now…and calculate with ur school endpoint.

Replace our 21.20 in 1bi and re-do the calculation with ur own titre value u placed there.

If your school wants to use mine, then the chemistry teacher must submit endpoint similar to ours without much difference…eg 21.15, 21.20, 21.20, 21.30, 21.40, etc

The answer you got in 1bi, use it to solve 1bii.
Example: we calculated 0.04 x 21.20 / 25.00 and got 0.03392 but if u replaced our 21.20 with ur school’s endpoint, u won’t get same 0.03392 with us.

Then u can see we used 0.03392 we got in 1bi to solve in 1bii and used the answer we got to solve 1biii. So when u replace, remember to re-calculate in all.

You are a science student, you should definitely understand what I meant.

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NECO Chemistry Specimen Practice Questions

CHEMISTRY PRACTICAL SPECIMEN:

Requirements:
(a) One burette (50cm³)
(b) One pippete (20cm³/25cm³). However, all
candidates in a center must use pipettes of the
same volume.
(c) The usual apparatus and reagents for
qualitative work including:
(i) Dilute sodium hydroxide solution
(ii) Dilute ammonia solution
(iii) Dilute hydrochloric acid
(iv) Barium chloride solution
(v) Distilled water
(vi) Red and Blue litmus paper
(vii) Phenolphtalein
(d) Methyl orange
(e) One boiling tube
(f) Five test tubes
(g) Filtration apparatus
(h) Source of heat
Each candidate should be supplied with the
following: Labelled An, Bn, Cn, where ‘n’ is the
candidate’s serial number.
(a) 150cm³ of chloride acid solution in a bottle
labelled “An”. The acid solution which should
be the same for all candidates will contain
3.4cm³ of the concentrated hydrochloric acid
per dm³ solution.
(b) 150cm³ of sodium hydroxide solution in a
bottle labelled “Bn”. The solution which should
be the same for all candidates will contain
4.0g of sodium hydroxide per dm³ of solution.
(c) One spatulaful of copper (ii)
tetraoxosulphate (vi) salt in a specimen bottle
labelled “Cn”.

The questions below are strictly for practice not the 2021 Chemistry expo.

All your burette readings (initials and final) as well as the size of your pipette must be recorded but no account of experimented procedure is required. All calculations must be done in your booklet.

  1. A is O.200 moldm3 of HCI. C is a solution containing 14/3g of Na2CO3. x H2O in 500 cm3 of solution. (a) Put A into the burette and titrate it against 20.0 cm3 or 25.0 cm3 portions of C using methyl orange as indicator. Repeat the titration to obtain Consistent titre values. Tabulate your results and calculate the average volume of A used. The equation for the reaction is: Na2CO3 x H2O + 2HCL(aq) → 2NaCI(aq) + CO2(g) + (x+1) H2O(I).

(b) From your results and the information provided. Calculate the: (i) concentration of C in moldm-3; (ii) concentration of C in gdm-3; (iii) molar mass of Na2CO3, xH2O; (iv) the value of x in Na2CO3 xH2O. [H = 1.0; C=12.0; O = 16.0; Na =23.0]

Credit will be given for strict adherence to the instruction, for observations precisely recorded and for accurate inferences. All tests, observations and influences must be clearly entered in the booklet in ink at the same time they are made.

2. F is a mixture to two inorganic salts. Carry out the following exercise on F. record your observation and identify any gas(s) evolved. State the conclusions you draw from the result of each test. (a) Put all of F in a beaker and add about 10cm3 of distilled water. Stir well and filter. Keep the filtrate and the residue. (b)(i) To about 2cm3 of the filtrate, add NaOH(aq) in drops and then in excess (ii) To another 2cm3 portion of the solution, add a few drops of NHO3(aq)followed by few drops of AgNO3(aq). (d)(i) Put all the residue into a clean test-tube and add NHO3(aq) followed by few solution from 2(d)(i) add NaOH(aq) in drops and then in excess.

3. State what would be observed if the following reactions are carried out in the laboratory: (i) methyl orange is dropped into a solution of lime juice (ii) hydrogen sulphide gas is bubbled through iron (III) chloride solution; (iii) sulphur (IV) oxide gas is bubbled into acidified solution of KMnO4; (iv) ethanoic acid is added to a solution of K2CO3.

CHEMISTRY PRACTICALS ANSWERS

  1. Indicator                                 =          Methyl Orange

Volume of the base used        =          25.00cm3

TitrationRough Titre1st Titre2nd Titre3rd Titre
Final Burette readings cm324.7024.8024.7024.90
Initial Burette reading cm30.000.000.000.00
Volume of acid used cm324.7024.8024.9024.90

Average Titre              =          1st + 2nd + 3rd/3

                                    =          24.80 + 24.70 + 24.90/3

                                    =          24.80cm3

Alternatively 2 concordant titres can be used to calculate average titre.

Equation of the reaction: Na2CO3 XH2O + 2HCI(aq) → 2NacI(aq) + CO2(aq) + (x+1)H2O(I)

CAVA/CBVB     =  nA/nB

CA = Molar concentration of HCI(aq) in moldm3

VA = Volume of acid used in cm3 = 24.80cm3

            CB = Molar concentration of Na2Cu3 xH2O in moldm3

nA = 2

nB = 1

(b)(i) concentration of C in moldm-3 = ? From the equation of reaction:

CAVA/CBVB     =  nA/nB

CA = 0.200 moldm3     VA = 24.80cm3

CB = ?                          VB = 25.00cm3

Substitution of known values

0.200 x 24.80/ CB x 25.00 = 2/1

CB = 1×0.200×24.80/2×25.00

C = 0.0992 moldm-3

(ii) Concentration of C in g dm-3 = ?

500cm2 → 14.3 g

1000cm3 →14.3/500 x 10002 g

= 28.6 g dm-3

(iii) Molar mass of Na2CO3 xH2O

Molar conc in moldm-3 = conc in g dm-3 / molar mass

Therefore: Molar mass g mol-1 = conc in g dm-3 / molar conc in moldm-3

                                                 = 28.6 g dm-3/0.0992 moldm-3

                                                 = 288.3065

                                    Approximately 288 g mol-1

(iv) Value of x in Na2CO3 xH2O?

[H = 1.0, C = 12.0, O = 16.0, Na = 23.0]

Na2CO3 xH2O = 288

2(23) + 12 + 3 (16) + x (2(I) + 16) = 288

46 + 12 + 48 + 18x  = 288

106 + 18x        = 288

            18x      = 288

            18x      = 182

               x       = 182/18

               x       = 10.11

               x approximately 10

2TestObservationInference
(a)F + distil water + stir + filterEffervescence (bubbling) occurs, colourless and odourless gas evolved after filtration pale blue/colourless filtrate and green residue 
(b)(i)Filtrate + NaOH(aq) in drops then in excessWhite precipitate formed   Precipitate insoluble in excess NaOH(aq)Ca2+/Pb2+   Ca2+ present
(b)(ii)Filtrate + NH3(aq) in drops then in excessNo visible reaction   No visible reaction ORCa2+ present   Ca2+ confirmed
(b)(i)Filtrate + NaOH(aq) in drops then in excessBlue gelatinous precipitate formed   Precipitate insoluble in excess    Cu2+  is present
(b)(ii)Filtrate + NH3(aq) in drops then in excessPale (light) blue gelatinous precipitate formed   Precipitate dissolves to form a deep blue solutionCu2+     Cu2+  is confirmed
(c)Filtrate + NHO3(aq) + AgNO3(aq)No visible reaction No gas involved White precipitate formedCuI-  is present
(d)(i)Residue + HNO3(aq)Effervescence occurs, colourless and odourless gas evolves that turns blue litmus paper to red and turns lime water milkyCO2(g) CO32- present
(d)(ii)Solution from 2(d)(i) + NaOH(aq) in drops then in excessBlue precipitate formed   Precipitate insoluble in excess NaOH(aq)Cu2+    Cu2+   present

3 (a)(i) Solution of lime juice turns to pink or red. (ii) The FeCI3 solution changes colour from brown to green and a yellow deposit. (iii) The purple colour of the KMnO4 solution turns colourless or decolourised. (iv) The solution of K2CO3 reacts with the addition of ethanoic acid to evolve a colourless, odourless gas with bubbling of effervescence.

If you have any questions about the 2021 NECO Chemistry Practical questions and answers, kindly let us know in the comment box.

Last Updated on July 13, 2023 by Admin

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136 thoughts on “NECO Chemistry Practical Questions and Answers 2023/2024 (Complete Solution)”

  1. please is this the answer for febuary 10 that we are writting today

    Reply
  2. Pls i need the Chemistry pratical question and answer pls

    Reply
  3. Is this real question and answer for the chemistry practical against February 10?

    Reply
  4. Please are this the question coming out for our practical on February 10.

    Reply
  5. Good day, please can I have the format of the practical questions, especially the question 1 and 3. I want to use it to teach my students that haven’t written the exam

    Reply
  6. Neco practicals is today,question and answer and donot forget the inference.

    Reply

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