Identify the INCORRECT pair with respect to the substances and their specific heat capacity (J kg-1K-1) at room temperature and atmospheric pressure.
- A.Aluminium - 900.0
- B.Water - 1200
- C.Carbon - 506.5
- D.Tungsten - 134.4
Correct answer
Explanation
The correct answer is B, Water - 1200. Water has a specific heat capacity of about 4186 joule per kilogram per kelvin, not 1200, so this pair is the wrong one. Specific heat capacity is the heat needed to raise the temperature of one kilogram of a substance by one kelvin, and water's value is the highest among common liquids. That is why water is used as a coolant in car radiators and industry, why the sea warms and cools slowly, and why coastal places have a milder climate than inland towns. A is a correct pair because aluminium takes about 900 joule per kilogram per kelvin. C is a correct pair because carbon in its graphite form is close to 506.5. D is a correct pair because tungsten, a heavy metal, needs only about 134.4, so metals heat up quickly. Exam tip: remember water as about 4186 joule per kilogram per kelvin, which is one calorie per gram per degree Celsius.
Practice Questions
View allThe fact that the planets move around the Sun, not in circles but in ellipses, was first demonstrated by
- A.Galileo
- B.Martin Luther
- C.Johannes Kepler
- D.Copernicus
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In 1609 Kepler showed that the planets move around the Sun in elliptical orbits, with the Sun at one focus of the ellipse.
Read the full explanation →Which one of the following statements is correct?
- A.Urea is produced in liver.
- B.Urea is produced in blood.
- C.Urea is produced from digestion of starch.
- D.Urea is produced in lung and kidney.
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Read the full explanation →Which one of the following is the correct sequence of passage of light in a compound microscope?
- A.Condenser-Objective lens-Eyepiece-Body tube
- B.Objective lens-Condenser-Body tube-Eyepiece
- C.Condenser-Objective lens-Body tube-Eyepiece
- D.Eyepiece-Objective lens-Body tube-Mirror
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Read the full explanation →Which one of the following statements regarding haemoglobin is correct?
- A.Haemoglobin present in RBC can carry only oxygen but not carbon dioxide.
- B.Haemoglobin of RBC can carry both oxygen and carbon dioxide.
- C.Haemoglobin of RBC can carry only carbon dioxide.
- D.Haemoglobin is only used for blood clotting and not for carrying gases.
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Read the full explanation →Which one of the following statements regarding histone proteins is correct?
- A.Histones are proteins that are present in mitochondrial membrane.
- B.Histones are proteins that are present in nucleus in association with DNA.
- C.Histones are proteins associated with lipids in the cytosol.
- D.Histones are proteins associated with carbohydrates in the cytosol.
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They are the proteins around which DNA winds to form chromatin in the nucleus of eukaryotic cells. Histones are small basic proteins, rich in the positively charged amino acids lysine and arginine, which attract the negatively charged phosphate groups of DNA.
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