Lesson: Acids, Bases, and Salts

Question:1

You have been provided with three test tubes. One of them contains distilled water and the other two contain an acidic solution and a basic solution, respectively. If you are given only red litmus paper, how will you identify the contents of each test tube?

Solution:

The content of the tube will be an acid if the colour of red litmus does not change when dipped into it.

It is a base if the colour of red litmus changes to blue.

If there is a slight change in the colour of red litmus (purple), then it is distilled water.

Question:2

Why should curd and sour substances not be kept in brass and copper vessels?

Solution:

Curd and other sour substances contain acids. Therefore, when they are kept in brass or copper vessels, the metal reacts with the acid. This results in release hydrogen gas and other harmful products. This spoils the food.

Question:3

Which gas is usually liberated when an acid reacts with a metal? Illustrate with an example. How will you test for the presence of this gas?

Solution:

Hydrogen gas is usually liberated when an acid reacts with a metal.

Take few pieces of zinc granules in a test tube.

Add 5 ml of dilute H 2 S O 4 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlh9frVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaamisa8aadaWgaaWcbaWdbiaaikda a8aabeaak8qacaWGtbGaam4ta8aadaWgaaWcbaWdbiaaisdaa8aabe aaaaa@4030@ .

Shake it and pass the gas produced through a soap solution.

Bubbles are formed in the soap solution are formed. These soap bubbles contain hydrogen gas.

H 2 S O 4 +ZnZnS O 4 + H 2 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlh9frVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaamisa8aadaWgaaWcbaWdbiaaikda a8aabeaak8qacaWGtbGaam4ta8aadaWgaaWcbaWdbiaaisdaa8aabe aak8qacqGHRaWkcaWGAbGaamOBaiabgkziUkaadQfacaWGUbGaam4u aiaad+eapaWaaSbaaSqaa8qacaaI0aaapaqabaGcpeGaey4kaSIaam isa8aadaWgaaWcbaWdbiaaikdaa8aabeaak8qacqGHrgsRaaa@4E65@

Now test if the evolved gas is hydrogen or not.

When a candle is brought near the soap bubbles the gas burns with a pop sound.

This proves that the evolved gas is hydrogen.

Question:4

Metal compound A reacts with dilute hydrochloric acid to produce effervescence. The gas evolved extinguishes a burning candle. Write a balanced chemical equation for the reaction if one of the compounds formed is calcium chloride.

Solution:

The metal compound formed due to the reaction is calcium chloride. This means that the metal compound has calcium metal. The gas that extinguishes a burning candle is carbon dioxide. This means the metal compound is calcium carbonate.

CaC O 3 ( s )+2HCl( aq )CaC l 2 ( aq )+C O 2 ( g )+ H 2 O( l ) MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlh9frVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaam4qaiaadggacaWGdbGaam4ta8aa daWgaaWcbaWdbiaaiodaa8aabeaakmaabmaabaWdbiaadohaa8aaca GLOaGaayzkaaWdbiabgUcaRiaaikdacaaMc8UaamisaiaadoeacaWG SbWdamaabmaabaWdbiaadggacaWGXbaapaGaayjkaiaawMcaa8qacq GHsgIRcaWGdbGaamyyaiaadoeacaWGSbWdamaaBaaaleaapeGaaGOm aaWdaeqaaOWaaeWaaeaapeGaamyyaiaadghaa8aacaGLOaGaayzkaa WdbiabgUcaRiaadoeacaWGpbWdamaaBaaaleaapeGaaGOmaaWdaeqa aOWaaeWaaeaapeGaam4zaaWdaiaawIcacaGLPaaapeGaey4kaSIaam isa8aadaWgaaWcbaWdbiaaikdaa8aabeaak8qacaWGpbWdamaabmaa baWdbiaadYgaa8aacaGLOaGaayzkaaaaaa@6281@

Question:5

Why do HCl MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlf9irVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaamisaiaadoeacaWGSbGaaGPaVdaa @3FAE@ , HN O 3 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlh9frVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaamisaiaad6eacaWGpbWdamaaBaaa leaapeGaaG4maaWdaeqaaaaa@3EFA@ , etc., show acidic characters in aqueous solutions while solutions of compounds like alcohol and glucose do not show acidic character?

Solution:

When HCl MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlf9irVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaamisaiaadoeacaWGSbGaaGPaVdaa @3FAE@  or HN O 3 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlh9frVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaamisaiaad6eacaWGpbWdamaaBaaa leaapeGaaG4maaWdaeqaaaaa@3EFA@  are mixed with water, they dissolve in water to form hydrogen ion ( H + ) MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlh9frVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaamaabmaabaaeaaaaaaaaa8qacaWGibWdamaaCaaaleqa baWdbiabgUcaRaaaaOWdaiaawIcacaGLPaaaaaa@3F0C@  or hydronium ion ( H 3 O + ) MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlh9frVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaamaabmaabaaeaaaaaaaaa8qacaWGibWdamaaBaaaleaa peGaaG4maaWdaeqaaOWdbiaad+eapaWaaWbaaSqabeaapeGaey4kaS caaaGcpaGaayjkaiaawMcaaaaa@4111@ . Due to the presence of these ions, these compounds show their acidic character.

When alcohol and glucose are mixed with water, they do form hydrogen or hydronium ions. Hence, they do not show acidic character.

Question: 6

Why does an aqueous solution of acid conduct electricity?

Solution:

Acids ionises in aqueous solutions.These ions are responsible for conducting electricity.

Question: 7

Why does dry HCl MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlf9irVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaamisaiaadoeacaWGSbaaaa@3E23@  gas not change the colour of the dry litmus paper?

Solution:

Dry HCl MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlf9irVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaamisaiaadoeacaWGSbaaaa@3E23@  does not show it acidic property unless it is dissolved in water. When dissolved in water, they form H + MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlh9frVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaamisa8aadaahaaWcbeqaa8qacqGH RaWkaaaaaa@3D6A@  or H 3 O + MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlh9frVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaamisa8aadaWgaaWcbaWdbiaaioda a8aabeaak8qacaWGpbWdamaaCaaaleqabaWdbiabgUcaRaaaaaa@3F6F@  ions. Due to these ions, these compounds show their acidic character. This ionization does not happen in case of dry HCl MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlf9irVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaamisaiaadoeacaWGSbaaaa@3E23@  gas and hence dry HCl MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlf9irVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaamisaiaadoeacaWGSbaaaa@3E23@  gas does not change the colour of the dry litmus paper.

Question: 8

While diluting an acid, why is it recommended that the acid should be added to water and not water to the acid?

Solution:

The reaction of acid and water is exothermic in nature. If water is added to an acid, the heat generated can cause burns. To slow down the generation of heat, it is always recommended that acid should be added to water.

Question: 9

How is the concentration of hydronium ions ( H 3 O + MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlh9frVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaamisa8aadaWgaaWcbaWdbiaaioda a8aabeaak8qacaWGpbWdamaaCaaaleqabaWdbiabgUcaRaaaaaa@3F6F@  ) affected when a solution of an acid is diluted?

Solution:

When water is added to a solution of acid, the solution becomes diluted.

The concentration of hydronium ions ( H 3 O + MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlh9frVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaamisa8aadaWgaaWcbaWdbiaaioda a8aabeaak8qacaWGpbWdamaaCaaaleqabaWdbiabgUcaRaaaaaa@3F6F@  ) decreases when a solution of an acid is diluted. This means that the strength of the acid decreases.

Question: 10

How is the concentration of hydroxide ions ( O H MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlh9frVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaam4taiaadIeapaWaaWbaaSqabeaa peGaai4eGaaaaaa@3E13@  ) affected when excess base is dissolved in a solution of sodium hydroxide?

Solution:

Sodium hydroxide is basic in nature. When excess base is dissolved in a solution of sodium hydroxide, the concentration of hydroxide ions ( O H MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlh9frVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaam4taiaadIeapaWaaWbaaSqabeaa peGaai4eGaaaaaa@3E13@  ) would increase.

Question: 11

You have two solutions, A and B. The pH of solution A is 6 and pH of solution B is 8. Which solution has more hydrogen ion concentration? Which of this is acidic and which one is basic?

Solution:

An acid has a pH value less than 7 while a base has a pH value more than 7.

The solution with pH=6 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlf9irVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaamiCaiaadIeacqGH9aqpcaaI2aaa aa@3F25@  is acidic and has more hydrogen ion concentration than the basic solution.

Question: 12

What effect does the concentration of H + MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlh9frVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaamisa8aadaahaaWcbeqaa8qacqGH RaWkaaaaaa@3D6A@  (aq) ions have on the nature of the solution?

Solution:

Concentration of H + MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlh9frVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaamisa8aadaahaaWcbeqaa8qacqGH RaWkaaaaaa@3D6A@  (aq) can have varied effects on the nature of the solution. If the concentration of H + MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlh9frVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaamisa8aadaahaaWcbeqaa8qacqGH RaWkaaaaaa@3D6A@  ions increases, the solution becomes more acidic. If the concentration of H + MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlh9frVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaamisa8aadaahaaWcbeqaa8qacqGH RaWkaaaaaa@3D6A@  ions decreases, the solution becomes more basic in nature.

Question: 13

Do basic solutions also have H + MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlh9frVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaamisa8aadaahaaWcbeqaa8qacqGH RaWkaaaaaa@3D6A@  (aq) ions? If yes, then why are these basic?

Solution:

Yes, basic solutions also have H + MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlh9frVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaamisa8aadaahaaWcbeqaa8qacqGH RaWkaaaaaa@3D6A@  (aq) ions. They are basic despite having H + MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlh9frVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaamisa8aadaahaaWcbeqaa8qacqGH RaWkaaaaaa@3D6A@  (aq) solution. This is due to the presence of less concentration of H + MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlh9frVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaamisa8aadaahaaWcbeqaa8qacqGH RaWkaaaaaa@3D6A@  (aq) compared to the concentration of O H MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlh9frVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaam4taiaadIeapaWaaWbaaSqabeaa peGaai4eGaaaaaa@3E13@  ions in the solutions.

Question: 14

Under what soil condition do you think a farmer would treat the soil of his fields with quick lime (calcium oxide) or slaked lime (calcium hydroxide) or chalk (calcium carbonate)?

Solution:

A plant grows the best when the soil is neither acidic not basic. The farmer would treat the soil with quick lime or slaked lime or chalk when the soil is acidic in nature. Quick lime or slaked lime or chalk are basic in nature and neutralizes the acidic nature of the soil when they are added to it.

Question:15

What is the common name of the compound CaOC l 2 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlh9frVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaam4qaiaadggacaWGpbGaam4qaiaa dYgapaWaaSbaaSqaa8qacaaIYaaapaqabaaaaa@40C0@ ?

Solution:

The common name of the compound CaOC l 2 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlh9frVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaam4qaiaadggacaWGpbGaam4qaiaa dYgapaWaaSbaaSqaa8qacaaIYaaapaqabaaaaa@40C0@  is bleaching powder.

Question:16

Name the substance which on treatment with chlorine yields bleaching powder.

Solution:

Calcium hydroxide [ Ca ( OH ) 2 ] MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlh9frVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaamaadmaabaaeaaaaaaaaa8qacaWGdbGaamyya8aadaqa daqaa8qacaWGpbGaamisaaWdaiaawIcacaGLPaaadaWgaaWcbaWdbi aaikdaa8aabeaaaOGaay5waiaaw2faaaaa@4378@

Question: 17

Name the sodium compound which is used for softening hard water.

Solution:

Washing soda ( N a 2 C O 3 .10 H 2 O ) MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlh9frVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaamaabmaabaaeaaaaaaaaa8qacaWGobGaamyya8aadaWg aaWcbaWdbiaaikdaa8aabeaak8qacaWGdbGaam4ta8aadaWgaaWcba Wdbiaaiodaa8aabeaak8qacaGGUaGaaGymaiaaicdacaaMc8Uaamis a8aadaWgaaWcbaWdbiaaikdaa8aabeaak8qacaWGpbaapaGaayjkai aawMcaaaaa@4940@

Question: 18

What will happen if a solution of sodium hydro carbonate is heated?

Give the equation of the reaction involved.

Solution:

When a solution of sodium hydro carbonate is heated, sodium carbonate and water are formed. Carbon dioxide too is released in this process.

2NaHC O 3 Heat  N a 2 C O 3 + H 2 O+C O 2 MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbmLMB1H hicL2BSLMB11garmWu51MyVXgaruWqVvNCPvMCG4uz3bqefqvATv2C G4uz3bIuV1wyUbqee0evGueE0jxyaibaieYlh9frVeeu0dXdh9vqqj =hEeeu0xXdbba9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXd ar=Jb9hs0dXdbPYxe9vr0=vr0=vqpWqaaeaabaGaciaacaqabeaada abauaaaOqaaabaaaaaaaaapeGaaGOmaiaaykW7caWGobGaamyyaiaa dIeacaWGdbGaam4ta8aadaWgaaWcbaWdbiaaiodaa8aabeaakmaaoq caleaacaWGibGaamyzaiaadggacaWG0baabeGccaGLsgcapeGaaiiO aiaad6eacaWGHbWdamaaBaaaleaapeGaaGOmaaWdaeqaaOWdbiaado eacaWGpbWdamaaBaaaleaapeGaaG4maaWdaeqaaOWdbiabgUcaRiaa dIeapaWaaSbaaSqaa8qacaaIYaaapaqabaGcpeGaam4taiabgUcaRi aadoeacaWGpbWdamaaBaaaleaapeGaaGOmaaWdaeqaaaaa@5658@

Question:19

Write an equation to show the reaction between Plaster of Paris and water.

Solution:

CaSO 4 . 1 2 H 2 O+1 1 2 H 2 O CaSO 4 .2H 2 O  POP              Water           Gypsum MathType@MTEF@5@5@+= feaagKart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr 4rNCHbGeaGqiVC0xe9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq=Jc9 vqaqpepm0xbba9pwe9Q8fs0=yqaqpepae9pg0FirpepeKkFr0xfr=x fr=xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGceaqabeaacaqGdb GaaeyyaiaabofacaqGpbWaaSbaaSqaaiaabsdaaeqaaOGaaeOlamaa laaabaGaaeymaaqaaiaabkdaaaGaaeisamaaBaaaleaacaqGYaaabe aakiaab+eacaqGRaGaaeymamaalaaabaGaaeymaaqaaiaabkdaaaGa aeisamaaBaaaleaacaqGYaaabeaakiaab+eacqGHsgIRcaqGdbGaae yyaiaabofacaqGpbWaaSbaaSqaaiaabsdaaeqaaOGaaeOlaiaabkda caqGibWaaSbaaSqaaiaabkdaaeqaaOGaae4taaqaaabaaaaaaaaape GaaiiOaiaaykW7caaMc8UaaGPaVlaaykW7caaMc8UaaGPaVlaaykW7 caaMc8Uaaeiuaiaab+eacaqGqbGaaeiOaiaabckacaqGGcGaaeiOai aabckacaqGGcGaaeiOaiaabckacaqGGcGaaeiOaiaabckacaqGGcGa aeiOaiaabckacaqGxbGaaeyyaiaabshacaqGLbGaaeOCaiaabckaca qGGcGaaeiOaiaabckacaqGGcGaaeiOaiaabckacaqGGcGaaeiOaiaa bckacaqGGcGaae4raiaabMhacaqGWbGaae4CaiaabwhacaqGTbaaaa a@84E5@