Each of the observations in the following list was made on a different solution. Given the observations, state which ion studied in this experiment is present. If the test is not definitive, indicate that with a question mark.
A. Addition of
Ion present:
B. Addition
Ion present:
C. Addition of
Ion present:
D. Addition of
Ion present:
E. Addition of
Ion present:
F. Addition of
Ion present:
(a)
Interpretation:
To identify the ion present in the solution that gives the observation: The addition of 6 M NaOH and Al to the solution produces a vapor that turns red litmus blue.
Concept Introduction :
Different ions (Cations or anions) present in the solution can be detected using different tests as these ions behave differently in terms of their chemical reactions.
Answer to Problem 1ASA
Nitrate ion (
Explanation of Solution
This test is known as Devarda’s test and is given by nitrate ions (
In this test, Devarda’s alloy (Al alloy) acts as a reducing agent and is reacted with nitrate ion in the sodium hydroxide (NaOH) solution. As a result, ammonia gas is produced that turns red litmus blue.
The reaction taking place is-
Hence, the ion present is the Nitrate ion.
(b)
Interpretation:
To identify the ion present in the solution that gives the observation: Adding 6 M HCl produces a vapor with an acrid odor.
Concept Introduction :
Different ions (Cations or anions) present in the solution can be detected using different tests as these ions behave differently in terms of their chemical reactions.
Answer to Problem 1ASA
Sulfite ion (
Explanation of Solution
Acrid odor is a strong smell that may cause a burning sensation in the throat.
This acrid odor represents the release of Sulfur dioxide (
And
Hence, the ion present is the sulfite ion.
(C)
Interpretation:
To identify the ion present in the solution that gives the observation: Adding 6 M HCl produces an effervescence.
Concept Introduction :
Different ions (Cations or anions) present in the solution can be detected using different tests as these ions behave differently in terms of their chemical reactions.
Answer to Problem 1ASA
Carbonate ion (
Explanation of Solution
Effervescence formation means carbon dioxide gas is released during this test and carbonate ions release
Hence, the ion present is the Carbonate ion.
(D)
Interpretation:
To identify the ion present in the solution that gives the observation: Adding 6 M
Concept Introduction :
Different ions (Cations or anions) present in the solution can be detected using different tests as these ions behave differently in terms of their chemical reactions.
Answer to Problem 1ASA
Halide ions (
Explanation of Solution
This test is a Silver nitrate test and is given by halide ions (
In this test, Silver ions react with halide ions to form the precipitate of silver halides. Nitric acid is added to remove interfering ions.
Hence, the ion present is either chloride ions or bromide ions, or iodide ions.
(E)
Interpretation:
To identify the ion present in the solution that gives the observation: Adding of 6 M
Concept Introduction :
Different ions (Cations or anions) present in the solution can be detected using different tests as these ions behave differently in terms of their chemical reactions.
Answer to Problem 1ASA
Sulfate (
Explanation of Solution
Sulfate (
Hence, the ion present is a sulfate ion.
(F)
Interpretation:
To identify the ion present in the solution that gives the observation: Adding of 6 M
Concept Introduction :
Different ions (Cations or anions) present in the solution can be detected using different tests as these ions behave differently in terms of their chemical reactions.
Answer to Problem 1ASA
Phosphate (
Explanation of Solution
Phosphate (
Hence, the ion present is the phosphate ion.
Want to see more full solutions like this?
Chapter 35 Solutions
Chemical Principles in the Laboratory
- Table 4.5 (data)Unmelted sample Melted sampleSolution Color_______________ ____________Result of adding AgNO3 to test solution______________ _____________Result of adding NH4SCN to test solution_____________ _____________Result of adding K4Fe(CN)6 to test solution____________ _____________4.6 (report)Test or observation is a composition change indicated?Solution color _________(Yes or no)Addition of AgNo3 _________(Yes or no)Addition of NH4SCN _________(Yes or no)Addition of K4Fe(CN)6 _________(Yes or no)arrow_forwardExplain why ammonium nitrate was chosen as the salt bridge electrolyte in our experiment. (Hint: Why would sodium chloride not be a suitable choice?)arrow_forwardUse some or all the data below to calculate the concentration of acetic acid (in M) in the Walmart bottle. Remember 1 molecule of NaOH neutralizes 1 molecule of acetic acid. Assume you titrated a 100.00 mL solution containing 1.00 mL of the Walmart vinegar. Data: Concentration of NaOH: 0.08467 M Titrant initial buret reading: 30.21 mL Final buret reading: 38.37 mLarrow_forward
- An acid sample of unknown concentration is contained in a Erlenmeyer flask. Which technique below would be best suited to analytically determine the number of moles of HCl in the sample? a.) Using a pipette b.) Distillation c.) Using a beaker d.) Titrationarrow_forwardIn following these steps . Complete the table and provide th given chemical reactions in the qualitative analaysis of Group 3 Cations. Procedure 1. Place 20 drops of each of the following aqueous solutions to separate centrifuge tubes: 0.1M Cr (NO3)3, 0.1M Al (NO3)3, 0.1M Co (NO3)2, 0.1M Zn (NO3)2, 0.1M Mn (OH)2, 0.1M Ni (NO3)2, 0.1 M Fe (NO3)3. Make each solution basic by adding few drops of 6M NH4OH. Confirm using a litmus paper. 2. Add 5 drops of freshly prepared 6M (NH4)2S to each centrifuge tube. Place the samples in thecentrifuge machine for 3 mins. After centrifuge record results. Decant the supernatant liquid of all the samples. 3. Add one drop of NH4OH in each centrifuge tubes. Add 20 drops of distilled water in eachcentrifuge tubes. Then add a few drops of 6M HCl in each solution. Place the samples in the water bath for 10 mins. After water bath, centrifuge the samples for 3 mins. 4. After centrifuge, add a few drops of 6M NH4Cl in each sample. Decant the supernatant liquid…arrow_forwardPlease help me answer 1 and 2 with solutionarrow_forward
- 6. Explain the reason why a laboratory analyst should not return excess or unused chemicals back in their respective reagent bottles.arrow_forwardA 25.0 mL sample of vinegar was analyzed via titration in the same manner as you will use in this experiment. The standardized solution of NaOH was 0.950 M. A total of 10.5 mL of the sodium hydroxide were required to reach the pink endpoint. What was the concentration of the acetic acid in the vinegar solution?arrow_forwardCan you help me find the answers for #4 and #5? Please show me the proper solutions, so I can study it. Thank you so mucharrow_forward
- A student adds one big iron nail each in four test tubes containing solution of zinc sulphate, aluminium sulphate, copper sulphate and iron sulphate. A reddish brown coating was observed only on the surface of iron nail which was added in the solution of:(a) Zinc sulphate(b) Iron sulphate(c) copper sulphate(d) Aluminium sulphatearrow_forwardwhat glassware should be used to add the sodium hydroxide into the hydrochloric acid solution? A. Volumetric pipette b. Graduated cylinder c. Volumetric flash d. Erlyn mayer flasharrow_forwardWrite a step-by-step prodcedure how how to create 100.0 mL of a 0.024 M solution of potassium iodate from a 0.048 M solution of potassium iodate (pretend you are creating this procedure for someone unfamiliar to chemistry and making solutions; be specific in your procedure and show your calculations)arrow_forward
- Chemical Principles in the LaboratoryChemistryISBN:9781305264434Author:Emil Slowinski, Wayne C. Wolsey, Robert RossiPublisher:Brooks Cole