Acids, Bases and Salts

What is the taste of acids?
a) Bitter
b) Sour
c) Sweet
d) Salty
Answer: b) Sour

What is the taste of bases?
a) Sweet
b) Sour
c) Bitter
d) Salty
Answer: c) Bitter

Which indicator changes from blue to red in the presence of an acid?
a) Phenolphthalein
b) Methyl orange
c) Red litmus
d) Blue litmus
Answer: d) Blue litmus

Which substance turns a red litmus blue?
a) Acid
b) Base
c) Salt
d) Neutral
Answer: b) Base

What is the chemical formula of hydrochloric acid?
a) H₂O
b) HCl
c) H₂SO₄
d) CH₃COOH
Answer: b) HCl

What is formed when an acid reacts with a metal?
a) Salt and water
b) Salt and oxygen
c) Salt and hydrogen gas
d) Hydrogen and oxygen
Answer: c) Salt and hydrogen gas

What is the gas produced when carbonates react with acids?
a) Oxygen
b) Hydrogen
c) Carbon dioxide
d) Methane
Answer: c) Carbon dioxide

Which of the following is an olfactory indicator?
a) Litmus
b) Phenolphthalein
c) Vanilla
d) Methyl orange
Answer: c) Vanilla

What happens when an acid reacts with a base?
a) Water is formed
b) Salt is formed
c) Both a) and b)
d) Hydrogen gas is released
Answer: c) Both a) and b)

What is the common name of sodium bicarbonate?
a) Washing soda
b) Baking soda
c) Bleaching powder
d) Rock salt
Answer: b) Baking soda

Which gas is evolved when zinc reacts with hydrochloric acid?
a) Oxygen
b) Hydrogen
c) Nitrogen
d) Carbon dioxide
Answer: b) Hydrogen

What is the pH of a neutral solution?
a) 0
b) 7
c) 14
d) 10
Answer: b) 7

Which of the following solutions has the highest concentration of H⁺ ions?
a) pH 1
b) pH 4
c) pH 7
d) pH 10
Answer: a) pH 1

What is the color of phenolphthalein in a basic solution?
a) Colorless
b) Pink
c) Yellow
d) Orange
Answer: b) Pink

Which natural indicator is derived from lichen?
a) Methyl orange
b) Litmus
c) Phenolphthalein
d) Turmeric
Answer: b) Litmus

What is the formula for calcium hydroxide?
a) CaO
b) Ca(OH)₂
c) CaCO₃
d) CaCl₂
Answer: b) Ca(OH)₂

What does the term “alkali” refer to?
a) Acidic salts
b) Soluble bases
c) Neutral solutions
d) Indicators
Answer: b) Soluble bases

Which acid is commonly found in vinegar?
a) Citric acid
b) Acetic acid
c) Tartaric acid
d) Oxalic acid
Answer: b) Acetic acid

Which reaction is known as a neutralization reaction?
a) Acid + Metal → Salt + Hydrogen
b) Acid + Base → Salt + Water
c) Acid + Carbonate → Salt + Carbon dioxide + Water
d) Acid + Non-metal oxide → Salt + Water
Answer: b) Acid + Base → Salt + Water

What happens to the pH when a solution is diluted?
a) Increases
b) Decreases
c) Remains the same
d) Depends on the solution
Answer: d) Depends on the solution

Which gas is responsible for turning lime water milky?
a) Oxygen
b) Nitrogen
c) Carbon dioxide
d) Hydrogen
Answer: c) Carbon dioxide

What is the chemical formula of gypsum?
a) CaSO₄
b) CaSO₄·2H₂O
c) CaCO₃
d) CaCl₂
Answer: b) CaSO₄·2H₂O

What happens to the color of turmeric when a base is added?
a) Remains yellow
b) Turns red
c) Turns blue
d) Turns green
Answer: b) Turns red

Which acid is present in lemon juice?
a) Tartaric acid
b) Oxalic acid
c) Citric acid
d) Methanoic acid
Answer: c) Citric acid

What is the pH range of an acidic solution?
a) 0-7
b) 7-14
c) 0-14
d) 5-9
Answer: a) 0-7

What is the chemical name of bleaching powder?
a) Calcium chloride
b) Calcium oxychloride
c) Calcium carbonate
d) Calcium hydroxide
Answer: b) Calcium oxychloride

What is the product of the reaction between NaOH and HCl?
a) NaCl and water
b) NaCl and hydrogen
c) NaOH and H₂O
d) H₂O and oxygen
Answer: a) NaCl and water

Which substance is used to relieve indigestion?
a) Bleaching powder
b) Baking soda
c) Washing soda
d) Vinegar
Answer: b) Baking soda

What is the chemical formula of sodium carbonate?
a) NaHCO₃
b) Na₂CO₃
c) Na₂CO₃·10H₂O
d) NaCl
Answer: b) Na₂CO₃

What is the nature of non-metallic oxides?
a) Acidic
b) Basic
c) Neutral
d) Amphoteric
Answer: a) Acidic

Which gas is released during the electrolysis of brine at the cathode?
a) Hydrogen
b) Oxygen
c) Chlorine
d) Sodium
Answer: a) Hydrogen

What is the formula for plaster of Paris?
a) CaSO₄·2H₂O
b) CaSO₄·½H₂O
c) CaCO₃
d) CaCl₂
Answer: b) CaSO₄·½H₂O

What is the pH of fresh milk?
a) 4
b) 5
c) 6
d) 7
Answer: c) 6

What happens when acids are dissolved in water?
a) Release H⁺ ions
b) Release OH⁻ ions
c) No reaction occurs
d) Form a precipitate
Answer: a) Release H⁺ ions

What is the color of copper sulphate crystals?
a) Green
b) Blue
c) White
d) Brown
Answer: b) Blue

What is formed when carbon dioxide reacts with lime water?
a) Calcium hydroxide
b) Calcium carbonate
c) Calcium oxide
d) Calcium chloride
Answer: b) Calcium carbonate

Which indicator is colorless in acids and pink in bases?
a) Litmus
b) Phenolphthalein
c) Methyl orange
d) Turmeric
Answer: b) Phenolphthalein

What is the pH of rainwater during acid rain?
a) More than 7
b) Less than 5.6
c) Equal to 7
d) Between 6-7
Answer: b) Less than 5.6

What is the name of the salt used to soften hard water?
a) Baking soda
b) Sodium carbonate
c) Calcium carbonate
d) Sodium chloride
Answer: b) Sodium carbonate

What causes tooth decay?
a) Bacteria produce acid when sugar is broken down
b) High pH in the mouth
c) Corrosion of enamel due to hydrogen
d) High concentration of hydroxide ions
Answer: a) Bacteria produce acid when sugar is broken down

Which process is highly exothermic?
a) Dilution of acid
b) Reaction of base with water
c) Both a and b
d) None of the above
Answer: c) Both a and b

What happens when water is added to concentrated acid?
a) The solution becomes cold
b) It may cause splashing and burns
c) No reaction occurs
d) The acid becomes weaker
Answer: b) It may cause splashing and burns

What is the role of universal indicators?
a) To determine pH
b) To measure conductivity
c) To neutralize acids
d) To measure temperature
Answer: a) To determine pH

What is the product of heating baking soda?
a) Sodium carbonate
b) Carbon dioxide
c) Water
d) All of the above
Answer: d) All of the above

Which of these acids is found in tamarind?
a) Tartaric acid
b) Acetic acid
c) Lactic acid
d) Oxalic acid
Answer: a) Tartaric acid

What is the cause of burning pain from a bee sting?
a) Methanoic acid
b) Citric acid
c) Acetic acid
d) Tartaric acid
Answer: a) Methanoic acid

Which base is commonly used in soap making?
a) Sodium hydroxide
b) Potassium hydroxide
c) Both a and b
d) Magnesium hydroxide
Answer: c) Both a and b

What is the main component of antacids?
a) Sodium chloride
b) Magnesium hydroxide
c) Sulphuric acid
d) Baking soda
Answer: b) Magnesium hydroxide

What happens when gypsum is heated at 373K?
a) Forms Plaster of Paris
b) Forms lime water
c) Becomes calcium chloride
d) Forms quicklime
Answer: a) Forms Plaster of Paris

Which salt is used in soda-acid fire extinguishers?
a) Sodium carbonate
b) Sodium hydrogencarbonate
c) Sodium chloride
d) Sodium hydroxide
Answer: b) Sodium hydrogencarbonate

What is the chemical formula of baking soda?
a) NaHCO₃
b) Na₂CO₃
c) CaCO₃
d) NaOH
Answer: a) NaHCO₃

Which gas is liberated when baking soda reacts with an acid?
a) Hydrogen
b) Oxygen
c) Carbon dioxide
d) Nitrogen
Answer: c) Carbon dioxide

What is the color of hydrated copper sulphate crystals?
a) White
b) Blue
c) Green
d) Yellow
Answer: b) Blue

What is the pH of the stomach’s hydrochloric acid?
a) 1-2
b) 4-5
c) 6-7
d) 8-9
Answer: a) 1-2

What does the pH scale measure?
a) Temperature
b) Pressure
c) Hydrogen ion concentration
d) Volume
Answer: c) Hydrogen ion concentration

What is the chemical name of washing soda?
a) Sodium chloride
b) Sodium carbonate
c) Sodium hydrogencarbonate
d) Calcium carbonate
Answer: b) Sodium carbonate

What happens when plaster of Paris reacts with water?
a) Becomes gypsum
b) Becomes washing soda
c) Becomes baking soda
d) Forms lime
Answer: a) Becomes gypsum

Which compound is responsible for tooth enamel damage?
a) Hydrochloric acid
b) Acetic acid
c) Lactic acid
d) Sulphuric acid
Answer: c) Lactic acid

Which gas is evolved when acids react with carbonates?
a) Hydrogen
b) Carbon dioxide
c) Oxygen
d) Methane
Answer: b) Carbon dioxide

What is the pH of a strongly basic solution?
a) Less than 7
b) Exactly 7
c) More than 10
d) Between 6 and 7
Answer: c) More than 10

What type of reaction occurs between an acid and a base?
a) Combustion
b) Displacement
c) Neutralization
d) Decomposition
Answer: c) Neutralization

What happens when a bee sting is treated with baking soda?
a) The acid is neutralized
b) More pain is caused
c) Hydrogen gas is released
d) Carbon dioxide is formed
Answer: a) The acid is neutralized

Which of the following is a weak acid?
a) Hydrochloric acid
b) Acetic acid
c) Sulphuric acid
d) Nitric acid
Answer: b) Acetic acid

What is the main ingredient in antacids?
a) Sodium hydroxide
b) Magnesium hydroxide
c) Potassium hydroxide
d) Calcium carbonate
Answer: b) Magnesium hydroxide

Which substance is used to test for the presence of carbon dioxide?
a) Lime water
b) Phenolphthalein
c) Turmeric
d) Litmus
Answer: a) Lime water

What happens when sodium hydroxide reacts with water?
a) Heat is absorbed
b) Heat is released
c) No reaction occurs
d) It produces oxygen gas
Answer: b) Heat is released

What is the general formula for the reaction between an acid and a metal carbonate?
a) Acid + Carbonate → Salt + Water + Carbon dioxide
b) Acid + Carbonate → Salt + Hydrogen
c) Acid + Carbonate → Water + Oxygen
d) Acid + Carbonate → Base + Salt
Answer: a) Acid + Carbonate → Salt + Water + Carbon dioxide

What is the use of bleaching powder in water treatment?
a) To add taste to water
b) To kill germs
c) To increase hardness
d) To neutralize the water
Answer: b) To kill germs

Which solution has a pH of 1?
a) Strong base
b) Strong acid
c) Weak acid
d) Neutral solution
Answer: b) Strong acid

What is the nature of ammonium hydroxide?
a) Neutral
b) Basic
c) Acidic
d) Amphoteric
Answer: b) Basic

What is formed when acids react with metal oxides?
a) Salt and water
b) Salt and hydrogen
c) Water and oxygen
d) Base and hydrogen
Answer: a) Salt and water

What is the pH range of human blood?
a) 5.5-6.5
b) 6.8-7.2
c) 7.0-7.8
d) 8.0-9.0
Answer: c) 7.0-7.8

What does the addition of HCl to water produce?
a) Na⁺ ions
b) H⁺ ions
c) OH⁻ ions
d) None of the above
Answer: b) H⁺ ions

Which substance is amphoteric in nature?
a) Sodium hydroxide
b) Calcium hydroxide
c) Zinc oxide
d) Sodium chloride
Answer: c) Zinc oxide

What is the main use of sodium carbonate?
a) Fire extinguisher
b) Softening hard water
c) Neutralizing acids
d) Cleaning jewelry
Answer: b) Softening hard water

What is the molecular formula of lime water?
a) CaCO₃
b) Ca(OH)₂
c) CaO
d) CaSO₄
Answer: b) Ca(OH)₂

What happens when acids react with bases?
a) Salt and water are formed
b) Hydrogen is released
c) Carbon dioxide is formed
d) Oxygen is released
Answer: a) Salt and water are formed

Which compound is used in soda-acid fire extinguishers?
a) Sodium chloride
b) Sodium hydrogencarbonate
c) Sodium hydroxide
d) Calcium carbonate
Answer: b) Sodium hydrogencarbonate

Which ion is responsible for basicity?
a) OH⁻
b) H⁺
c) CO₃²⁻
d) SO₄²⁻
Answer: a) OH⁻

What is the formula of ammonium hydroxide?
a) NH₄Cl
b) NH₄OH
c) NH₃OH
d) NH₃
Answer: b) NH₄OH

What is formed when calcium carbonate reacts with HCl?
a) Calcium chloride, water, and carbon dioxide
b) Calcium oxide and carbon dioxide
c) Calcium hydroxide and oxygen
d) Calcium sulphate and water
Answer: a) Calcium chloride, water, and carbon dioxide

What is the chemical name of quicklime?
a) Calcium carbonate
b) Calcium oxide
c) Calcium hydroxide
d) Calcium sulphate
Answer: b) Calcium oxide

What is the color of methyl orange in a basic medium?
a) Red
b) Orange
c) Yellow
d) Colorless
Answer: c) Yellow

Which acid is used in car batteries?
a) Acetic acid
b) Sulphuric acid
c) Nitric acid
d) Hydrochloric acid
Answer: b) Sulphuric acid

What type of acid is lactic acid?
a) Strong acid
b) Weak acid
c) Neutral acid
d) Inorganic acid
Answer: b) Weak acid

What is the pH of distilled water?
a) 6
b) 7
c) 8
d) 9
Answer: b) 7

Which compound is used in glass manufacturing?
a) Sodium carbonate
b) Baking soda
c) Sodium chloride
d) Calcium carbonate
Answer: a) Sodium carbonate

What is the cause of acid rain?
a) Carbon dioxide
b) Sulphur dioxide and nitrogen oxides
c) Hydrogen gas
d) Methane
Answer: b) Sulphur dioxide and nitrogen oxides

Which gas is evolved when sodium carbonate reacts with acids?
a) Carbon dioxide
b) Hydrogen
c) Oxygen
d) Methane
Answer: a) Carbon dioxide

What is the chemical formula of rock salt?
a) NaCl
b) Na₂CO₃
c) CaSO₄
d) NaHCO₃
Answer: a) NaCl

What is the nature of hydrochloric acid?
a) Strong acid
b) Weak acid
c) Strong base
d) Neutral
Answer: a) Strong acid

What is the role of antacids?
a) Neutralize stomach acid
b) Strengthen bones
c) Increase acidity
d) Kill bacteria
Answer: a) Neutralize stomach acid

Which of the following salts is acidic?
a) Sodium acetate
b) Ammonium chloride
c) Sodium chloride
d) Calcium carbonate
Answer: b) Ammonium chloride

What is the main compound in bleaching powder?
a) CaOCl₂
b) CaCl₂
c) NaCl
d) Na₂CO₃
Answer: a) CaOCl₂

Which acid is present in ant stings?
a) Methanoic acid
b) Acetic acid
c) Tartaric acid
d) Citric acid
Answer: a) Methanoic acid

What is the chemical formula of hydrogen chloride gas?
a) HCl
b) H₂SO₄
c) HNO₃
d) CH₃COOH
Answer: a) HCl

What is the primary use of phenolphthalein?
a) Measuring pH
b) Testing acidity and basicity
c) Treating indigestion
d) Softening hard water
Answer: b) Testing acidity and basicity

What is the molecular formula of citric acid?
a) C₆H₈O₇
b) CH₃COOH
c) H₂SO₄
d) C₆H₆
Answer: a) C₆H₈O₇

What is the pH of soap solution?
a) Less than 7
b) Exactly 7
c) Greater than 7
d) 0
Answer: c) Greater than 7

What is the effect of acid rain on soil?
a) Increases pH
b) Decreases pH
c) No effect
d) Neutralizes the soil
Answer: b) Decreases pH