Qualitative Analysis

Carry out the following tests using FA 3 and record your observations in Table 3.1.
Use a $1\text{ cm}$ depth of FA 3 in a test-tube for each test.

Give the formula of the gas formed in Test 3.

The gas formed is .............................. .

FA 7 is a solution containing four ions, three of which are listed in the Qualitative analysis notes.
Carry out the following tests and record your observations in Table 3.2.

Use a $1\text{ cm}$ depth of FA 7 for each test. A boiling tube must be used for Test 1 and a test-tube for the other tests.

Give the formula of each of the four ions in FA 7.

The ions are ........................ , ........................ , ........................ and ........................ .

Give the ionic equation for one reaction that takes place in Test 1 or Test 3 of (b)(i).
Include state symbols.

Carry out the following tests and record your observations in Tables 3.1 and 3.2. For each test use a $1\text{ cm}$ depth of FA 7 in a test-tube unless the solution requires heating.

Write an ionic equation for a reaction in (a)(i) that resulted in the formation of a precipitate. Include state symbols.

Give the formula of each ion present in FA 7. If you cannot identify an ion, write 'unknown.'

cations ..................... and .....................

anion .....................

Transfer a spatula measure of FA 8 to a hard-glass test-tube. Heat the test-tube gently at first, then more strongly until no further change occurs. Record your observations.

The FA 9 provided is a sample of the residue obtained from heating FA 8.

To a $2\text{ cm}$ depth of nitric acid in a test-tube, slowly add a small spatula measure of FA 9. Record your observations.

Deduce the formula of FA 8.

FA 8 is ......................... .

Transfer a $2\text{ cm}$ depth of FA 2, $\text{KMnO}_4$, into a test-tube. Add the same volume of aqueous sodium hydroxide followed by a small spatula measure of FA 5, $\text{MnO}_2$. Stir for approximately 30 seconds then filter the mixture into a second test-tube.

observations ......................................................................................................................

Add dilute sulfuric acid to the filtrate until no further change.

observations ......................................................................................................................

Transfer a $1\text{ cm}$ depth of aqueous iron(II) sulfate into a boiling tube. Add the same depth of dilute sulfuric acid followed by a very small spatula measure of FA 5, $\text{MnO}_2$. Carefully warm the mixture using a Bunsen burner for about 20 seconds. Filter the warm mixture into a test-tube.

observations ......................................................................................................................

Add aqueous sodium hydroxide dropwise to the filtrate until no further change.

observations ......................................................................................................................

Suggest a conclusion about the chemical behaviour of FA 5 using your observations in (a)(ii).

FA 5 is acting as ..........................................................................................................

Write an ionic equation for the reaction between aqueous sodium hydroxide and the filtrate in (a)(ii). Include state symbols.

Carry out the following tests and record your observations in Table 3.1.

Use a $1\text{ cm}$ depth of FA 6 or FA 7 in a boiling tube for Test 1. Use a $1\text{ cm}$ depth of FA 6 or FA 7 in a test-tube for Tests 2, 3 and 4.

The anion in FA 6 does not contain nitrogen. Select one further reagent to identify the anion present in FA 6.

Carry out a test with this reagent and record your observations in Table 3.2.

Give the formulae of the ions present in FA 6 and FA 7. If you are unable to identify an ion from your tests, write ‘unknown.’

The ions present in FA 6 are ......................... and ......................... and ......................... .

The ions present in FA 7 are ......................... and ......................... .

Devise and carry out tests to investigate whether zinc ions, sulfate ions and water of crystallisation are present.

Record the tests you carry out and the observations you see in the space provided.

Use your observations in (a)(i) to complete Table 3.1 to show whether each species is present in FA 5.

Use a tick (✓) if the species is present.
Use a cross (✗) if the species is not present.

Heat a few crystals of FA 6 in a hard-glass test-tube until no further gas is evolved. Record all your observations.

Leave the test-tube until it is cool.

Keep the cooled residue for use in (b)(ii).

To the cooled residue from (b)(i), add approximately $3 \text{ cm}$ depth of distilled water and stir. Filter the solution formed into a test-tube.

The colour of the solution is .............................. .

Carry out the following tests on FA 7, FA 8 and FA 9 and record your observations in Table 3.2. For each test use a $1 \text{ cm}$ depth of a solution or a spatula measure of solid.

Suggest the identity of the metal in FA 6/FA 7, FA 8 and FA 9.

The metal is .............................. .

Complete Table 3.3 to suggest the oxidation state of the metal in FA 6/FA 7 and FA 8.

To a $1\text{ cm}$ depth of FB 4 in a boiling tube, slowly add a $1\text{ cm}$ depth of dilute nitric acid. Stir gently until the reaction is complete. Use this solution for your tests.

Select reagents to identify which sodium halide is present.
Record details of the reagents used and your observations.
Identify the sodium halide that is present as an impurity in FB 4.

The formula of the impurity is ...............

Suggest why it is necessary to add the nitric acid to FB 4 before carrying out your tests in (a)(i).

Place half the sample of FB 7 in a hard-glass test-tube. Heat gently at first and then more strongly.

Record your observations.

Use the $25\text{ cm}^3$ measuring cylinder to measure $20\text{ cm}^3$ of FB 1.

Place the remaining sample of FB 7 in a boiling tube and add portions of FB 1 from the measuring cylinder until all the FB 7 has reacted. Stir until the reaction is complete.

Record your observations.

Keep this solution for use in (b)(iii).

Carry out the following tests. For each test use a $1\text{ cm}$ depth of the solution from (b)(ii) in a test-tube.

Record your observations in Table 3.1.
Identify the metal ion present in FB 7.

Table 3.1

The formula of the metal ion in FB 7 is ...............

Carry out the following tests. For each test use a $1\text{ cm}$ depth of FB 8 in a test-tube.

Record your observations in Table 3.2.
Identify the metal ion present in FB 8.

Table 3.2

The formula of the metal ion in FB 8 is ...............

State the type of reaction between the metal ion in FB 8 and acidified aqueous potassium manganate(VII).

Explain how your observations support your answer.

Devise and carry out tests to investigate whether zinc ions, sulfate ions and water of crystallisation are present.

Record the tests you carry out and the observations you see in the space provided.

Use your observations in (a)(i) to complete Table 3.1 to show whether each species is present in FA 5.

Use a tick (✓) if the species is present.
Use a cross (✗) if the species is not present.

Table 3.1

Heat a few crystals of FA 6 in a hard-glass test-tube until no further gas is evolved. Record all your observations.

Leave the test-tube until it is cool.

Keep the cooled residue for use in (b)(ii).

To the cooled residue from (b)(i), add approximately $3 \text{ cm}$ depth of distilled water and stir. Filter the solution formed into a test-tube.

The colour of the solution is .............................. .

Carry out the following tests on FA 7, FA 8 and FA 9 and record your observations in Table 3.2. For each test use a $1 \text{ cm}$ depth of a solution or a spatula measure of solid.

Suggest the identity of the metal in FA 6/FA 7, FA 8 and FA 9.

The metal is .............................. .

Complete Table 3.3 to suggest the oxidation state of the metal in FA 6/FA 7 and FA 8.

Table 3.3

Use very small quantities of solid FB 5 and carry out each of the tests described in Table 3.1.
Identify any gases produced.

FB 6 is the filtrate obtained after filtering the mixture that remains at the end of Test 3 in (a)(i).
Add aqueous ammonia to FB 6.
Record your observations.

Identify FB 5.

FB 5 is ............................. .

Using your observations, explain why the reaction in Test 2 is a redox reaction.

Give the ionic equation for the first reaction observed in (a)(ii). Include state symbols.

Transfer a small spatula measure of FB 7 into a hard-glass test-tube.
Heat gently at the start, then strongly until no further change occurs.
Leave the test-tube to cool.

Record all your observations. Identify any gases produced.

Carry out one further positive test to confirm the identity of the anion in FB 7.

Record only the results shown in a positive test.
Describe the test you carry out and the observations you make in the space below.

The anion in FB 7 is ............................. .

You are supplied with strips of magnesium ribbon. You must not use any other reagents in this part of the question.

Carry out tests to identify each of the three solutions, FA 7, FA 8 and FA 9.
Obtain as much evidence as you can for your identifications.
Use a $1\text{ cm}$ depth of solution in a test-tube for each test you carry out.

Record all your observations.

Give the ionic equation for the reaction of magnesium with FA 8. Include state symbols.

Carry out the following tests and record your observations in Table 3.1.

For Tests 1 and 2, use a $1\text{ cm}$ depth of FA 10 or FA 11 in a test-tube.
For Test 3, use a $1\text{ cm}$ depth of FA 10 or FA 11 in a boiling tube.

Table 3.1

Use your observations in (b)(i) to complete Table 3.2 by identifying the formulae of the ions present in FA 10 and FA 11.

If you cannot identify an ion write ‘unknown’.

Table 3.2

Place a small spatula measure of FB 4 into a hard-glass test-tube. Heat the tube gently at first and then more strongly.

Record all your observations and identify any gas given off.

Carry out the following tests using a $1\text{ cm}$ depth of this FB 4 solution in a test-tube for each test. Record your observations in Table 3.1.

Table 3.1

Use your observations in Table 3.1 to identify two anions which must be present in FB 4.

Carry out further tests to confirm or identify which two cations are present in FB 4.

Record the reagents and conditions needed, your observations and your conclusions in a suitable table.

FA 5 contains one cation and one anion, both of which are listed in the Qualitative analysis notes. FA 5 is insoluble in water.

Transfer approximately half of the sample of FA 5 into a hard-glass test-tube. Heat the test-tube gently at first, then more strongly, until no further change occurs.
Record all your observations.

To a $2\text{ cm}$ depth of FA 6 in a test-tube, add a piece of magnesium ribbon.
Record all your observations.

Write an ionic equation for the reaction between FA 6 and magnesium. Include state symbols.

Add a small spatula measure of FA 5 to a $2\text{ cm}$ depth of FA 6 in a boiling tube.
Record all your observations.

The product of this test is FA 7. Label the boiling tube FA 7.

To a $1\text{ cm}$ depth of FA 7 in a test-tube, add aqueous ammonia.
Record all your observations.

The same anion is present in both FA 6 and FA 7. The identity of this anion can be confirmed by testing either FA 6 or FA 7 with a pair of reagents.

Select two pairs of reagents which may be used to identify the anion present in both FA 6 and FA 7.

first pair of reagents:
\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots and \dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots

second pair of reagents:
\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots and \dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots

Use FA 6 to carry out each test using the two pairs of reagents you have selected. Record all your observations in a suitable form below.

Use your observations in (a) to (d) to identify the ions present in FA 5 and FA 6. If you are unable to identify an ion write 'unknown'.