Experimental techniques and chemical analysis — IGCSE Chemistry (0620) questions by topic

Which substances can be used to detect the presence of water? 1 anhydrous cobalt(II) chloride 2 anhydrous copper(II) sulfate 3 litmus 4 methyl orange A 1 and 2 B 1 and 3 C 2 and 4…

Excess solid magnesium oxide is added to dilute nitric acid. Which separation technique is used to remove the excess solid magnesium oxide after the reaction finishes? A…

Four different aqueous metal nitrates are tested separately with aqueous sodium hydroxide, with dilute sulfuric acid and with a flame test. Which row shows the correct set of…

Which diagram shows the correct level of solvent at the start of a chromatography experiment? A the level of solvent is above the spot of sample (solvent covers the sample spot) B…

Which process is used to separate a mixture of liquids with different boiling points? A dissolving B crystallisation C filtration D fractional distillation

Four different colourless solutions are each tested separately with aqueous sodium hydroxide and with acidified aqueous silver nitrate. Which row shows the results for sodium…

Three compounds are listed. 1 aluminium nitrate 2 ammonium chloride 3 ammonium nitrate All three compounds are heated with aqueous sodium hydroxide. Which compounds produce…

Three coloured inks, P, Q and R, are tested using paper chromatography. The chromatogram is shown. On the chromatogram, ink P produced two spots, ink Q produced three spots (one…

The table shows the results of two separate tests on a sample of aqueous T. test observation --- --- flame test yellow flame add dilute nitric acid effervescence What is the…

Which item of apparatus is used to measure 25.0 cm³ of aqueous sodium hydroxide? Four pieces of laboratory apparatus are drawn: A. a teat/dropping pipette (small dropper) B. a…

Which method is used to obtain copper(II) sulfate crystals from an aqueous solution of copper(II) sulfate? A. chromatography B. condensation C. evaporation D. filtration

A mixture of four different colourless amino acids is analysed by paper chromatography. The final chromatogram is shown: a strip of paper with a baseline near the bottom and a…

Water is added separately to anhydrous copper(II) sulfate and to anhydrous cobalt(II) chloride. Which row shows the colour changes? anhydrous copper(II) sulfate anhydrous…

Which item of apparatus is used to measure exactly 26.3 cm^3 of a liquid? The four options A-D are diagrams of pieces of apparatus: A is a burette, B is a syringe, C is a…

A mixture containing an aqueous salt and an insoluble salt is filtered. The diagram shows a filter funnel containing filter paper (labelled X) above a conical flask, with the…

Pure ethanol has a melting point of -114 °C and a boiling point of 78 °C. What are the melting and boiling points of a sample of ethanol with glucose dissolved in it? melting…

Anhydrous copper(II) sulfate and anhydrous cobalt(II) chloride change colour when water is added to them. Which row shows the correct colour changes? copper(II) sulfate cobalt(II)…

The steps used to separate a mixture of a soluble solid and an insoluble solid are listed. - A solution is made by adding the mixture to a suitable ...1... . - The mixture is…

Which items of apparatus are used to separate a mixture of liquids with different boiling points? Four sets of apparatus are shown: A a distillation set-up (round-bottomed flask…

In paper chromatography, what is the equation for the Rf value? A Rf = (distance travelled by solvent) / (distance travelled by substance) B Rf = (distance travelled by locating…

Tests on solid F. To the boiling tube containing solid F, add about 15 cm3 of dilute hydrochloric acid. Test any gas produced. Keep the product for use in (b). Record your…

You are provided with two solids: solid J and solid K. Do the following tests on solid J and solid K. Record all of your observations at each stage. Tests on solid J Add about 5…

Magnesium sulfate is a salt. Magnesium sulfate is soluble in water. The solubility of a salt is the mass of the salt, in g, that dissolves in 100 cm3 of water at a specified…

Complete Table 1.1 by calculating the volume of dilute sulfuric acid added to the conical flask.

The student adds about 15 cm^3 of dilute hydrochloric acid to the sample of solid F (calcium carbonate) in a boiling tube and tests any gas produced. State the observations.

Tests on solid J. Solid J is iron(II) iodide. The student dissolves solid J in water to form solution J. Solution J is divided into four portions. To the first portion of solution…

Magnesium sulfate is a salt. Magnesium sulfate is soluble in water. The solubility of a salt is the mass of the salt, in g, that dissolves in 100 cm3 of water at a specified…

Use the information in the description of the experiments and the stop-watch diagrams to complete Table 2.1. Table 2.1 experiment volume of aqueous sodium thiosulfate /cm3 volume…

To the first portion of solution L, the student adds aqueous sodium hydroxide dropwise and then in excess. observations when added dropwise ............ observations in excess…

Substance X and four known substances, P, Q, R and S, are analysed by chromatography. The chromatogram shows X producing spots level with P and S, plus one additional spot at a…

Copper is insoluble in water. Copper(II) oxide is a solid that is insoluble in water but reacts with dilute hydrochloric acid. Which method is used to separate copper from a…

A salt, S, is dissolved in water and three tests are carried out on the solution formed: test 1 aqueous sodium hydroxide is added — green precipitate forms, insoluble in excess…

Which row identifies methods of testing the purity of a compound? (columns: melting point; boiling point; chromatography) A ✓; ✓; ✓ B ✓; ✗; ✗ C ✓; ✓; ✗ D ✗; ✓; ✓

The equation for the hydration of anhydrous copper(II) sulfate is shown: CuSO4 + 5H2O → CuSO4·5H2O Which colour change is observed in this reaction? A blue to white B white to…

Which statement shows that a liquid is pure water? A It boils at 100 °C. B It has a pH value of 7. C It turns blue cobalt(II) chloride pink. D It turns white copper(II) sulfate…

Sea water contains dissolved sodium chloride. Which method is used to obtain pure water from sea water? A chromatography B distillation C evaporation D filtration

Which piece of apparatus is used to measure exactly 21.4 cm³ of water? A a 25 cm³ beaker B a 25 cm³ pipette C a 50 cm³ burette D a 50 cm³ measuring cylinder

An aqueous solution of compound M is tested. The results are: a lilac colour in a flame test; a white precipitate when tested with acidified barium nitrate. What is compound M? A…

Which reaction produces a white-coloured substance? A adding water to anhydrous cobalt(II) chloride B adding water to anhydrous copper(II) sulfate C heating hydrated cobalt(II)…

Two tests are carried out on substance Z: test 1 a flame test produces a red flame; test 2 Z is dissolved in water and dilute nitric acid is added, followed by aqueous silver…

Which gas is produced when ammonium chloride is warmed with aqueous sodium hydroxide? A ammonia B chlorine C hydrogen D nitrogen

Which statement identifies a sample of water as pure? A It melts at room temperature. B It turns anhydrous copper(II) sulfate blue. C It turns hydrated cobalt(II) chloride from…

Which statement about chromatography is correct? A It is not possible for two different substances to have the same Rf value. B It is only possible to use chromatography on…

Which statement about water is correct? A It turns anhydrous copper(II) sulfate from pink to blue. B It turns anhydrous copper(II) sulfate from white to blue. C It turns…

Which piece of apparatus is used to measure 24.5 cm³ of gas produced during a reaction? A beaker B conical flask C measuring cylinder D volumetric pipette

Four pure substances, P, Q, R and S, are tested using chromatography. The same solvent is used each time. The table shows the distance moved by each substance and by the solvent…

A substance is tested with three different reagents. Which row shows the results obtained with aqueous iron(II) nitrate? (columns: aqueous sodium hydroxide; acidified aqueous…

A student carries out a flame test on a sample. The flame colour observed is light green. Which ion is present in the sample? A Ba²⁺ B Ca²⁺ C Li⁺ D K⁺

You are provided with two substances: solid H and solid I. Do the following tests on the substances, recording all of your observations at each stage. Tests on solid H (a)(i) Add…

A student tests two substances: solution E and solid F. Tests on solution E. Solution E is aqueous chromium(III) bromide. Solution E is divided into two portions. Record the…

A mixture contains three compounds: liquid ethanol; solid sodium chloride; solid zinc carbonate. Table 4.1 gives some information about these three compounds: ethanol (soluble in…

When a mixture of calcium hydroxide and ammonium chloride is heated, ammonia gas is made. calcium hydroxide + ammonium chloride - calcium chloride + water + ammonia Ammonia gas is…

A student tests two substances: solid H and solution I. Tests on solid H. Solid H is barium carbonate. Complete the expected observations. (a)(i) The student adds an excess of…

A sample of rock salt contains sodium chloride, sand and mud. Sodium chloride is soluble in water. Sand and mud are insoluble in water. A student obtains dry crystals of pure…

A student tests two substances: solid K and solution L. Tests on solid K. Solid K is copper(II) carbonate. Complete the expected observations. (a) The student adds about 5 cm3 of…

Dyes are coloured substances. The chromatogram of substance X and four different dyes, 1, 2, 3 and 4, is shown (spots run from a baseline; X shows two spots that line up with two…

The results of two tests on substance G are listed. - A flame test produces a yellow flame. - Substance G is added to aqueous sodium hydroxide and powdered aluminium and warmed…

When a few drops of water are added to a solid, E, the colour changes from blue to pink. What is E? A anhydrous cobalt(II) chloride B anhydrous copper(II) sulfate C hydrated…

Sample M contains calcium carbonate and sodium nitrate. The result of adding water to M, stirring and filtering is shown (calcium carbonate remains on the filter paper, aqueous…

Ammonium chloride reacts with solution X to produce alkaline gas Y. The equation is shown. ammonium chloride + solution X - alkaline gas Y Which row identifies X and Y? X Y ---…

A mixture containing an aqueous salt, sand and hot water is stirred. The mixture is then poured into a filtration apparatus (filter funnel and filter paper over a beaker). X is…

Which row shows how the boiling point and the melting point of water change when a soluble impurity is added to the water? boiling point melting point --- --- --- A increases…

X is a white powder. The following tests are done on X. - When a few drops of aqueous sodium hydroxide are added to a solution of X, no precipitate is seen. - When X is heated…

Pure solid copper(II) nitrate can be obtained from a mixture of copper(II) nitrate and copper powder. Three stages in the method are listed. X add water and stir Y crystallise Z…

Which row describes a test and the observation for aqueous sulfate ions? test observation --- --- --- A add dilute nitric acid a gas is produced which turns limewater cloudy B add…

The chromatogram of substance S is shown, with distances W, X, Y and Z labelled: Z is the distance from the baseline to the solvent front, and the spot of substance S is between…

Some information about solid silver chloride and solid sodium chloride is shown. - Silver chloride and sodium chloride do not dissolve in kerosene. - Silver chloride is insoluble…

Which statement describes how a flame test is done? A The tip of a clean wire is dipped into the substance and the wire is placed in a blue Bunsen burner flame. B The tip of a…

You are provided with two solids: solid M and solid N. Do the following tests on solid M and solid N. Record all of your observations at each stage. Tests on solid M: Carry out a…

You are provided with two solids: solid R and solid S. Do the following tests on solid R and solid S, recording all of your observations at each stage. Tests on solid R: Transfer…

A mixture contains three solid compounds: aluminium oxide, calcium carbonate and calcium chloride. Table 3.1 gives some information about the three compounds in the mixture (name…

A student has a mixture of copper(II) carbonate powder and crystals of sodium sulfate. Copper(II) carbonate is insoluble in water. Sodium sulfate is soluble in water. The student…

A student tests two solids: solid T and solid U. Tests on solid T: solid T is lithium sulfite. Complete the expected observations. The student carries out a flame test on solid T.…

Beetroot is a coloured vegetable. The colour is caused by a mixture of water-soluble coloured compounds. Plan an experiment to find how many water-soluble coloured compounds there…

A student tests two substances: solid M and solid N. Tests on solid M: Table 3.1 shows the tests and the student's observations for solid M. Test 1 (flame test on solid M) → lilac…

A student tests two solids: solid R and solid S. Tests on solid R: Table 3.1 shows the tests and the student's observations for solid R. Test 1 (gently heat about half of solid R…

A mixture contains three solid compounds: aluminium oxide, calcium carbonate and calcium chloride. Table 4.1 gives some information about the three compounds in the mixture (name…

A student tests two solids: solid E and solid F. Table 3.1 shows the tests on solid E and the student's observations: test 1 — gently heat half of solid E in a boiling tube: a…

A student tests two substances: solution F and solid G. Table 3.1 shows the tests and observations for solution F (divided into three portions): test 1 — flame test on the first…

This question is about separating mixtures. The apparatus in Fig. 1.1 can be used to separate a mixture of liquids with different boiling points (a round-bottomed flask of liquid…

A student tests two solids: solid G and solid H. Solid G contains three ions. Table 3.1 shows the observations for solid G: test 1 — flame test on solid G: lilac coloured flame.…

Fig. 2.1 shows the distillation apparatus that can be used to separate water from aqueous copper(II) sulfate. The apparatus consists of a distillation flask containing aqueous…

Aqueous hydrogen peroxide, H2O2, slowly forms water and oxygen at room temperature and pressure, r.t.p. This reaction is catalysed by manganese(IV) oxide: 2H2O2(aq) → 2H2O(l) +…

Answer the following questions using only the substances from the list (barium nitrate, carbon monoxide, hydrated cobalt(II) chloride, copper(II) oxide, anhydrous copper(II)…