Which one of the following solutions is not capable of conducting electricity?
- A.Copper sulphate
- B.Sodium chloride
- C.Sugar
- D.Sodium hydroxide
Correct answer
Explanation
The correct answer is C, Sugar. Sugar dissolves in water as whole, neutral molecules and releases no ions, so its solution does not conduct electricity.
A solution conducts only when it contains free ions that can carry charge between the electrodes. Substances that split into ions in water are called electrolytes; those that do not, like sugar (sucrose), glucose, urea and alcohol, are non-electrolytes. Sucrose is a covalent compound, so its molecules stay intact in water. Pure distilled water is also a very poor conductor; tap water conducts because of the dissolved salts in it.
A, copper sulphate, splits into Cu²⁺ and SO₄²⁻ ions; its solution conducts and is used in electroplating with copper.
B, sodium chloride, gives Na⁺ and Cl⁻ ions, so salt water is a good conductor.
D, sodium hydroxide, is a strong base that gives Na⁺ and OH⁻ ions and conducts well.
Exam tip: acids, bases and salts in water conduct (electrolytes); sugar, glucose, urea and alcohol do not.
Practice Questions
View allRecently, there was a growing awareness in our country about the importance of Himalayan nettle (Girardinia diversifolia) because it is found to be a sustainable source of
- A.anti-malarial drug
- B.biodiesel
- C.pulp for paper industry
- D.textile fibre
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The Himalayan nettle yields a strong natural fibre that can be spun and woven into cloth. Girardinia diversifolia, known as Himalayan giant nettle or allo, is a stinging shrub that grows wild in the moist forests of the Himalayas, including Uttarakhand, Himachal Pradesh and the North-east, as well as Nepal.
Read the full explanation →Which of the following statements are correct regarding the general difference between plant and animal cells ? 1. Plant cells have cellulose cell walls whilst animal cells do not. 2. Plant cells do not have plasma membrane unlike animal cells which do. 3. Mature plant cell has one large vacuole whilst animal cell has many small vacuoles. Select the correct answer using the code given below:
- A.1 and 2 only
- B.2 and 3 only
- C.1 and 3 only
- D.1,2 and 3
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Plant cells have a cellulose wall and one large central vacuole, but they do have a plasma membrane, just like animal cells.
Read the full explanation →Consider the following statements : 1. In tropical regions, Zika virus disease is transmitted by the same mosquito that transmits dengue. 2. Sexual transmission of Zika virus disease is possible. Which of the statements given above is/are correct ?
- A.1 only
- B.2 only
- C.Both 1 and 2
- D.Neither 1 nor 2
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Zika is spread mainly by the Aedes mosquito that also carries dengue, and it can pass between sexual partners. The Zika virus is a flavivirus first identified in Uganda's Zika forest in 1947.
Read the full explanation →What is the importance of using Pneumococcal Conjugate Vaccines in India ? 1. These vaccines are effective against pneumonia as well as meningitis and sepsis. 2. Dependence on antibiotics that are not effective against drug-resistant bacteria can be reduced. 3. These vaccines have no side effects and cause no allergic reactions. Select the correct answer using the code given below :
- A.1 only
- B.1 and 2 only
- C.3 only
- D.1, 2 and 3
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Read the full explanation →Which one of the following is NOT true for bleaching powder?
- A.It is used as a reducing agent in chemical industries
- B.It is used for bleaching wood pulp in paper factories
- C.It is used for disinfecting drinking water
- D.It is used for bleaching linen in textile industry
Show answer
Bleaching powder is an oxidising agent, not a reducing agent, so this statement is the false one. Bleaching powder, calcium oxychloride (CaOCl₂), is made by passing chlorine gas over dry slaked lime, Ca(OH)₂.
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