Acids, Bases and Salts Overview
50 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

If someone in the family is suffering from a problem of acidity after overeating, which of the following would you suggest as a remedy: lemon juice, vinegar or baking soda solution?

  • baking soda solution (correct)
  • lemon juice
  • vinegar

    • Which property did you think of while choosing the remedy?

    The ability of acids and bases to nullify each other's effect.

    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?

  • The test tube containing the acidic solution will turn the red litmus paper blue.
  • All the test tubes will turn the red litmus paper blue.
  • The test tube containing the basic solution will turn the red litmus paper blue.
  • The test tube containing the acidic solution will turn the red litmus paper red. (correct)

    • Litmus solution is a purple dye, which is extracted from lichen, a plant belonging to the division Thallophyta, and is commonly used as an indicator.

    <p>True</p> Signup and view all the answers

    Which of these - vanilla, onion, and clove - can be used as olfactory indicators?

    <p>All of the above</p> Signup and view all the answers

    What do you observe on the surface of zinc granules when added to dilute sulphuric acid?

    <p>Bubbles are formed on the surface of the zinc granules.</p> Signup and view all the answers

    Why are bubbles formed in the soap solution when the gas is passed through it?

    <p>The hydrogen gas produced during the reaction between zinc and the acid is not soluble in water, and it forms bubbles in the soap solution.</p> Signup and view all the answers

    What do you observe when a burning candle is taken near the gas-filled bubble?

    <p>The gas will burn with a pop sound.</p> Signup and view all the answers

    The reaction of a metal with an acid can be summarized as Acid + Metal → Salt + Hydrogen gas

    <p>True</p> Signup and view all the answers

    Write the equations for reactions you have observed with zinc in dilute sulphuric acid, and zinc in sodium hydroxide.

    <p><strong>Zinc in dilute sulphuric acid:</strong> Zn(s) + H₂SO₄(aq) → ZnSO₄(aq) + H₂(g) <strong>Zinc in sodium hydroxide:</strong> 2NaOH(aq) + Zn(s) → Na₂ZnO₂(s) + H₂(g)</p> Signup and view all the answers

    Such reactions (of metal and acid) are not possible with all metals.

    <p>True</p> Signup and view all the answers

    What do you observe when you add dilute HCl to sodium carbonate and sodium hydrogencarbonate?

    <p>Effervescence is observed in both cases.</p> Signup and view all the answers

    Write the chemical equations for both reactions.

    <p><strong>Sodium carbonate reaction:</strong> Na₂CO₃(s) + 2HCl(aq) → 2NaCl(aq) + H₂O(l) + CO₂(g) <strong>Sodium hydrogencarbonate reaction:</strong> NaHCO₃(s) + HCl(aq) → NaCl(aq) + H₂O(l) + CO₂(g)</p> Signup and view all the answers

    What do you observe when you pass the gas evolved in each case through lime water?

    <p>A white precipitate is formed in the lime water in both cases.</p> Signup and view all the answers

    The reaction between an acid and a base to give a salt and water is known as a neutralisation reaction.

    <p>True</p> Signup and view all the answers

    Write a general equation for a neutralisation reaction.

    <p>Base + Acid → Salt + Water</p> Signup and view all the answers

    What happens when a small amount of copper oxide is added to dilute hydrochloric acid?

    <p>The copper oxide dissolves in the hydrochloric acid and the solution turns blue-green.</p> Signup and view all the answers

    Write a general equation for the reaction between a metal oxide and an acid.

    <p>Metal oxide + Acid → Salt + Water</p> Signup and view all the answers

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

    <p>Curd and sour substances contain acids, which react with the metal of the vessels (brass and copper) to form salts and release hydrogen gas. This can corrode the vessels and make the food unsafe to consume.</p> Signup and view all the answers

    Which gas is usually liberated when an acid reacts with a metal?

    <p>Hydrogen gas (H₂)</p> Signup and view all the answers

    Illustrate with an example. How will you test for the presence of this gas?

    <p>Example: Zinc reacts with dilute hydrochloric acid (HCl) to produce hydrogen gas (H₂). To test for the presence of hydrogen gas, you can pass the gas produced through a soap solution. The gas will form bubbles in the soap solution. You can then bring a burning candle near the bubble, and the hydrogen gas will burn with a pop sound.</p> Signup and view all the answers

    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.

    <p>CaCO₃(s) + 2HCl(aq) → CaCl₂(aq) + H₂O(l) + CO₂(g)</p> Signup and view all the answers

    All compounds containing hydrogen are acidic.

    <p>False</p> Signup and view all the answers

    What happens when solutions of glucose, alcohol, hydrochloric acid, sulphuric acid, etc. are tested with a 6-volt battery using a bulb and switch?

    <p>The bulb glows only with acids.</p> Signup and view all the answers

    Acids produce hydrogen ions, H+(aq), in solution which are responsible for their acidic properties.

    <p>True</p> Signup and view all the answers

    Acids produce ions only in aqueous solution.

    <p>True</p> Signup and view all the answers

    The effect of a base is nullified by an acid and vice versa.

    <p>True</p> Signup and view all the answers

    Bases generate hydroxide (OH-) ions in water.

    <p>True</p> Signup and view all the answers

    All bases dissolve in water.

    <p>False</p> Signup and view all the answers

    What happens when water is mixed with an acid or a base?

    <p>Mixing water with an acid or a base releases heat, making it an exothermic process. The heat released may be significant, especially when dealing with concentrated acids or bases. It is important to always add acid to water slowly and with constant stirring, never the other way around, to avoid splashing and potential burns.</p> Signup and view all the answers

    The strength of acids and bases depends on the number of H+ ions and OH- ions produced, respectively.

    <p>True</p> Signup and view all the answers

    Our body works within the pH range of 7.0 to 7.8.

    <p>True</p> Signup and view all the answers

    Living organisms can survive only in a narrow range of pH change.

    <p>True</p> Signup and view all the answers

    Rain water with pH less than 5.6 is called acid rain.

    <p>True</p> Signup and view all the answers

    The pH of the soil in your backyard affects the healthy growth of plants.

    <p>True</p> Signup and view all the answers

    Our stomach produces hydrochloric acid.

    <p>True</p> Signup and view all the answers

    Tooth decay starts when the pH of the mouth is lower than 5.5.

    <p>True</p> Signup and view all the answers

    Nettle stings cause pain and irritation. Use of a mild base like baking soda on the stung area gives relief.

    <p>True</p> Signup and view all the answers

    The common salt (NaCl) obtained is an important raw material for various materials of daily use, such as sodium hydroxide, baking soda, washing soda, bleaching powder and many more.

    <p>True</p> Signup and view all the answers

    When electricity is passed through an aqueous solution of sodium chloride (called brine), it decomposes to form sodium hydroxide. The process is called the chlor-alkali process because of the products formed - chlor for chlorine and alkali for sodium hydroxide.

    <p>True</p> Signup and view all the answers

    Bleaching powder is used for bleaching cotton and linen in the textile industry, for bleaching wood pulp in paper factories and for bleaching washed clothes in laundry.

    <p>True</p> Signup and view all the answers

    Baking soda is commonly used in the kitchen for making tasty crispy pakoras, etc. Sometimes it is added for faster cooking.

    <p>True</p> Signup and view all the answers

    Washing soda can be obtained by heating baking soda, recrystallisation of sodium carbonate gives washing soda. It is also a basic salt.

    <p>True</p> Signup and view all the answers

    When water is added to Plaster of Paris, it changes into gypsum, releasing heat - an exothermic process.

    <p>True</p> Signup and view all the answers

    What is the common name of the compound CaOCl₂?

    <p>Bleaching Powder</p> Signup and view all the answers

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

    <p>Calcium hydroxide, [Ca(OH)₂]</p> Signup and view all the answers

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

    <p>Sodium Carbonate (Na₂CO₃)</p> Signup and view all the answers

    What will happen if a solution of sodium hydrogencarbonate is heated?

    <p>When a solution of sodium hydrogencarbonate (NaHCO₃) is heated, it decomposes into sodium carbonate (Na₂CO₃), water (H₂O), and carbon dioxide gas (CO₂). The chemical equation for this reaction is: 2NaHCO₃(s) → Na₂CO₃(s) + H₂O(l) + CO₂(g).</p> Signup and view all the answers

    Give the equation of the reaction involved.

    <p>2NaHCO₃(s) → Na₂CO₃(s) + H₂O(l) + CO₂(g)</p> Signup and view all the answers

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

    <p>CaSO₄.½H₂O + 1½H₂O → CaSO₄.2H₂O</p> Signup and view all the answers

    Study Notes

    Acids, Bases and Salts

    • Acids have a sour taste and bases have a bitter taste
    • Acids turn blue litmus red and bases turn red litmus blue
    • Litmus is a natural indicator, turmeric is another
    • Synthetic indicators like methyl orange and phenolphthalein can also be used
    • Acids and bases can neutralise each other
    • Acids react with metals to produce salt and hydrogen gas
    • Acids react with metal carbonates and hydrogencarbonates to produce salt, water, and carbon dioxide
    • The reaction between an acid and a base is a neutralisation reaction, producing a salt and water
    • Metallic oxides act as bases
    • Non-metallic oxides act as acids
    • The pH scale measures the concentration of hydrogen ions in a solution
    • A pH of 7 is neutral, below 7 is acidic, above 7 is basic
    • Solutions of acids and bases conduct electricity because they produce ions
    • Acids, bases and certain salts have various uses in everyday life
    • Common salt (sodium chloride) is a raw material for many chemicals
    • Sodium hydroxide is produced by electrolysis of sodium chloride solution
    • Chlorine and hydrogen gases are also produced during electrolysis
    • Bleaching powder is made from chlorine and slaked lime
    • Baking soda and washing soda are also common products from sodium chloride
    • Salts are produced from the reaction of an acid with a base, or an acid with a metal, or a base with a metal
    • Salt crystals may contain water of crystallisation
    • Water of crystallisation can be removed by heating the crystals.
    • Examples of salts include sodium chloride, potassium nitrate, aluminum chloride, zinc sulfate, copper sulfate, sodium acetate, sodium carbonate, sodium hydrogencarbonate.

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    Acids, Bases, and Salts PDF

    Description

    Explore the fascinating world of acids, bases, and salts with this quiz. Learn about their properties, reactions, and everyday applications. Test your knowledge on indicators, the pH scale, and neutralisation reactions!

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser