Vinegar is also known as
- A.ethanoic acid
- B.nitric acid
- C.sulphuric acid
- D.tartaric acid
Correct answer
Explanation
The correct answer is A, ethanoic acid. Vinegar is a dilute solution of ethanoic acid, commonly called acetic acid, in water.
Vinegar contains about 5 to 8 per cent ethanoic acid (CH3COOH) and is made by the fermentation of sugar or alcohol by acetic acid bacteria. It is used as a preservative in pickles and sauces because its acidity stops microbes from growing. Pure ethanoic acid freezes at about 16.6°C, so in cold weather it forms ice-like crystals and is called glacial acetic acid. It is a weak organic acid that reacts with sodium carbonate to give off carbon dioxide.
B, nitric acid (HNO3), is a strong mineral acid used to make fertilisers and explosives, never eaten.
C, sulphuric acid (H2SO4), is a strong mineral acid known as the king of chemicals and used in car batteries.
D, tartaric acid, is found in tamarind and grapes and is a part of baking powder.
Exam tip: vinegar, acetic acid; tamarind, tartaric acid; curd, lactic acid; lemon, citric acid; ant sting, methanoic (formic) acid.
Practice Questions
View allThe principle involved in paper chromatography is
- A.Absorption
- B.Partition
- C.Solubility
- D.Volatility
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Read the full explanation →Which one of the following phenomena CANNOT be exhibited by sound waves ?
- A.Reflection
- B.Refraction
- C.Interference
- D.Polarisation
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Sound in air is a longitudinal wave, and only transverse waves can be polarised. Polarisation means restricting the vibrations of a wave to a single plane.
Read the full explanation →Which one of the following is NOT a luminous object ?
- A.Sun
- B.Electric lamp
- C.Candle
- D.Moon
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Read the full explanation →In experiment #1, a bar magnet is moved towards a conducting wire loop axially, with the magnet's north pole facing the loop. In experiment #2, the same process as in experiment #1 is repeated except that the south pole of the magnet faces the loop. Which one of the following statements is true in this context?
- A.The direction of current in the loop will be of opposite nature in both the experiments.
- B.The direction of current in the loop will be the same in both the experiments.
- C.No current will flow in either of the two experiments.
- D.More current will flow in the loop in experiment #1.
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Read the full explanation →Which one of the following statements about classification of plants is correct?
- A.Thallophytes have well differentiated body design
- B.Funaria is a fungus
- C.All Pteridophytes are Phanerogams
- D.Vascular system is not found among Bryophytes
Show answer
Mosses and liverworts have no xylem or phloem, so water moves through them cell to cell. Bryophytes, such as Funaria (a moss) and Marchantia (a liverwort), are called the amphibians of the plant kingdom because they live on land but need water for fertilisation.
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