Acids Bases & Salt

Q1: Which one of the following is acidic?

• Lemon juice
• Tomatoes
• Milk
• All

Q2: Which one of the given is a mineral acid?

• Lactic acid
• Formic acid
• Tartaric acid
• Hydrochloric acid

Q3: Which one of the following will turn red litmus blue?

• Vinegar
• Baking soda solution
• Lemon juice
• Soft drinks

Q4: Which one of the given is an organic acid?

• Citric acid
• Hydrochloric acid
• Lactic acid
• Both (1) & (3)

Q5: Which one of the following will turn blue litmus red?

• Vinegar
• Lime water
• Baking soda solution
• Washing soda solution

Q6: Which one of the given is incorrect?

• Acids turns blue litmus paper red
• Aqueous solutions of acids conduct electricity
• Acids react with certain metals to form hydrogen gas
• None of these

Q7: Methyl orange is

• Pink in acidic medium, yellow in basic medium
• Yellow in acidic medium, pink in basic medium
• Colourless in acidic medium, pink in basic medium
• Pink in acidic medium, colorless in basic medium

Q8: Which one of the given acids is used in the treatment of bone marrow and scurvy diseases?

• Acetic acid
• Hydrochloric acid
• Ascorbic acid
• Nitric acid

Q9: Lime water is

• CaO
• Ca(OH)2
• CaCO3
• CaCI2

Q10: Acid present in apple is :

• Oxalic acid
• Malic acid
• Acetic acid
• Formic acid

Q11: The nature of calcium phosphate is present in tooth enamel is

• Basic
• Amphoteric
• Acidic
• Neutral

Q12: Which one of the given is hydracid?

• H₃PO₄
• H₂SO₄
• HCN
• HNO₃

Q13: Which of the following salts has no water of crystallization?

• Blue vitriol
• Washing soda
• Baking soda
• Gypsum

Q14: Most of the oxides of metals when react with acid, form____

• A base
• An acid
• A salt
• Either (1) or (2)

Q15: The function of quick lime in soda lime mixture is to

• Absorb moisture present in soda lime
• Increase the efficiency of soda lime
• Increase the pH of soda lime
• Take part in reaction with NaOH

Q16: Generally, when certain metals react with an acid they release _______ gas.

• Nitrogen
• Oxygen
• Hydrogen
• Argon

Q17: The Ph of a solution of HCL is 4. This shows that the molarity of the solution is

• 4.0M
• 0.4M
• 0.0001M
• 0.001M

Q18: A strong acid:

• Completely gets ionized in water
• Partially gets ionized in water
• Do not get ionized in water
• All the these

Q19: Which of the given is a strong base?

• Calcium hydroxide
• Magnesium hydroxide
• Ammonium hydroxide
• Potassium hydroxide

Q20: Which one of the given is the pH value of pure water?

• 0
• 7
• 8
• 1

Q21: Which one of the given is true, if a substance has a pH value of 7?

• The substance is a base
• The substance is a acid
• The substance is a neutral substance
• None

Q22: Which one of the following is formed when calcium hydroxide reacts with carbon dioxide?

• Hydrogen gas
• Water
• Salt
• Both B and C

Q23: Which acid is used in cola to give it a biting sharp taste

• Sulphuric acid (H₂SO₄)
• Tartaric acid
• Phosphoric acid
• Citric acid

Q24: When acids dissolve in water it releases _____.

• H+ ion
• H- ion
• H₃O+ ion
• H₃O2+ ion

Q25: Which element is always present in Arrhenius acid?

• Oxygen
• Nitrogen
• Hydrogen
• None of these

Q26: During the preparation of HCl gas on a humid day, the gas is usually passed through the guard tube containing CaCl₂. The purpose of using CaCl₂ is

• To add moisture to the gas (HCl)
• To absorb HCl gas
• To absorb moisture from HCl gas
• To Use it as a catalyst

Q27: Black ash is

• Dry KOH
• Barium sulphide
• Charcoal
• Hydrated KOH

Q28: The pH of commonly used toothpaste is

• <6.5
• ≥7.0
• ≥2.2
• None of these

Q29: The pH of Gastric juice is

• <6.5
• ≥7.0
• 1.5 to 3.5
• None of these

Q30: The chemical formula of Plaster of Paris is

• CaSO₄,1/2H₂O
• CaSO₄, 2H₂O
• CaSO₄, H₂O
• CaSO₄, 3H₂O

Q31: What happens when a solution of an acid is mixed with a solution of a base in a test tube? (i) The temperature of the solution increases (ii) The temperature of the solution decreases (iii) The temperature of the solution remains the same (iv) Salt formation takes place

• (i) only
• (i) and (iii)
• (ii) and (iii)
• (i) and (iv)

Q32: Chemical formula of washing soda is

• Na₂C0₃ . 7H₂O
• Na₂C0₃ . 5H₂O
• Na₂C0₃ . 2H₂O
• Na₂C0₃ . 10H₂O

Q33: An aqueous solution turns red litmus solution blue. Excess addition of which of the following solution would reverse the change?

• Baking powder
• Lime
• Ammonium hydroxide solution
• Hydrochloric acid

Q34: Sodium hydroxide turns phenolphthalein solution

• pink
• yellow
• colourless
• orange

Q35: Two aqueous solutions P and Q have pH of 5 and 13 respectively. The correct inference is that:

• solution P is of HCl and Q is of NH4OH
• solution P is of CH3COOH and Q is of Ca(OH)₂
• solution P is of HNO₃ and Q is of NH4OH
• solution P is of CH3COOH and Q is of NaOH

Q36: Sodium hydroxide is used

• as an antacid
• in manufacture of soap
• as a cleansing agent
• in alkaline batteries

Q37: The pH of a solution is 7. How can you increase its pH?

• By adding a small amount of acid
• By adding a small amount of base.
• By adding a small amount of salt.
• By passing carbon dioxide gas through it

Q38: When copper oxide and dilute hydrochloric acid react, colour changes to

• white
• bluish-green
• blue-black
• black

Q39: Sodium carbonate is a basic salt because it is a salt of

• strong acid and strong base
• weak acid and weak base
• strong acid and weak base
• weak acid and strong base

Q40: An aqueous solution turns red litmus solution blue. Excess addition of which of the following solution would reverse the change?

• Baking powder
• Lime
• Ammonium hydroxide solution
• Hydrochloric acid

Q41: Which gas is evolved when acids react with metals?

• O₂
• CO₂
• H₂
• N₂

Q42: Sodium hydroxide is a

• weak base
• weak acid
• strong base
• strong acid

Q43: Which of the following gives the correct increasing order of acidic strength?

• Water < Acetic acid < Hydrochloric acid
• Water < Hydrochloric acid < Acetic acid
• Acetic acid < Water < Hydrochloric acid
• Hydrochloric acid < Water < Acetic acid

Q44: Rain is called acid rain when its:

• pH falls below 7
• pH falls below 6
• pH falls below 5.6
• pH is above 7

Q45: If a few drops of a concentrated acid accidentally spills over the hand of a student, what should be done?

• Wash the hand with saline solution.
• Wash the hand immediately with plenty of water and apply a paste of sodium hydrogencarbonate.
• After washing with plenty of water and apply solution of sodium hydroxide on the hand.
• Neutralise the acid with a strong alkali.

Q46: Farmers neutralise the effect of acidity of the soil by adding

• slaked lime
• gypsum
• caustic soda
• baking soda

Q47: What is the pH range of our body?

• 7.0 – 7.8
• 7.2 – 8.0
• 7.0 – 8.4
• 7.2 – 8.4

Q48: A teacher gave two test tubes to the students, one containing water and the other containing sodium hydroxide. She asked them to identify the test tube containing sodium hydroxide solution. Which one of the following can be used for identification?

• Blue litmus
• Red litmus
• Sodium carbonate solution
• Dilute hydrochloric acid

Q49: Tooth enamel is made up of

• calcium phosphate
• calcium carbonate
• calcium oxide
• potassium

Q50: Nettle sting is a natural source of which acid?

• Methanoic acid
• Lactic acid
• Citric acid
• Tartaric acid

Q51: Increase in the OH– ion concentration, leads to

• an increases in the pH of solution
• a decrease in the pH of the solution
• doesn’t alter the pH of the solution
• decreases the basic strength of the solution

Q52: Which of the following statements is correct about an aqueous solution of an acid and of a base? (i) Higher the pH, stronger the acid (ii) Higher the pH, weaker the acid (iii) Lower the pH, stronger the base (iv) Lower the pH, weaker the base

• (i) and (iii)
• (ii) and (iii)
• (i) and (iv)
• (ii) and (iv)

Q53: Lime water reacts with chlorine to give

• bleaching powder
• baking powder
• baking soda
• washing soda

Q54: Alkalis are

• acids, which are soluble in water
• acids, which are insoluble in water
• bases, which are insoluble in water
• bases, which are soluble in water

Q55: 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. Which of them will turn red litmus to blue.

• . Acid
• . Base
• . Water
• . All of the above

Q56: Acids react with metals to liberate _________gas

• . Carbon dioxide
• . Carbon monoxide
• . Hydrogen
• . Water

Q57: Acids react with metal carbonates to liberate ______ gas

• . Carbon dioxide
• . Carbon monoxide
• . Hydrogen
• . Water

Q58: Lime water turns milky when carbon dioxide is passed due to the formation of ______.

• . CaCO3
• . CaO
• . CO2
• . CaSO4

Q59: The milkiness (on passing excess carbon dioxide gas through lime water) disappears due to the formation of:

• . Calcium carbonate CaCO₃
• . Calcium hydrogen carbonate CaHCO₃
• . Calcium oxide CaO
• . Calcium Nitrate Ca(NO3)₂

Q60: Acids react with bases to form salt and water. This reaction is known as:

• . Combination
• . Decomposition
• . Neutralisation
• . reduction

Q61: A calcium compound reacts with dilute hydrochloric acid to produce effervescence. The gas evolved extinguishes a burning candle. Identify the compound and the gas evolved.

• . Calcium Carbonate, Carbon dioxide
• . Calcium chloride, carbon dioxide
• . Calcium oxide, hydrogen
• . Calcium carbonate, hydrogen

Q62: How is the concentration of hydronium ions (H3O+) affected when a solution of an acid is diluted?

• . Increases
• . Decreases
• . Remains the same
• . Becomes zero