This set of Food Chemistry Multiple Choice Questions & Answers (MCQs) focuses on “Water Molecules”.
1. How much is the dissociation energy of a water molecule?
a) 4.6×102
b) 4.5×105
c) 4.8×108
d) 5.2×105
View Answer
Explanation: Dissociation energy measures the strength of a chemical bond. Water has a dissociation energy of 4.6×102 KJ/mol or 110Kcal/mol.
2. Which one of the following is referred to as universal solvent?
a) Liquid nitrogen
b) Water
c) Hydrochloric acid
d) Mercury
View Answer
Explanation: Water is the most studied chemical compound. It is described as the ‘universal solvent’ due to its ability to dissolve many substances. This allows it to be ‘solvent of life’.
3. What is the boiling point of water?
a) 10°C
b) 100°C
c) 45°C
d) 80°C
View Answer
Explanation: Water in its solid form is less dense than in its liquid form. It has a relatively high boiling point of 100°C for its molar mass, and a high heat capacity. The freezing point of water is 0°C.
4. What is the IUPAC name of water?
a) Dihydro methane
b) Hydrogen peroxide
c) Hydrogen chloride
d) Oxidane
View Answer
Explanation: The IUPAC name of water is oxidane. Water is also called as hydrogen oxide.
5. What is the compressibility of water at 0°C and zero pressure?
a) 5.1×10-10
b) 6.2×1023
c) 3.6×1063
d) 8.5×10-15
View Answer
Explanation: It is a function of pressure and temperature. At 0°C and zero pressure, the compressibility of water is 5.1×10-10Pa-1
6. Which of the following does not apply to water?
a) The three atoms in the water molecule readily form hydrogen bond
b) Covalent bonds in water are highly polarized
c) Water molecules are asymmetric
d) Water molecules readily form hydrophobic interactions
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Explanation: The water molecule readily does not form hydrophobic interactions. They are asymmetric, highly polarized and easily forms hydrogen bonds.
7. The temperature and pressure at which solid, liquid, and gaseous water coexist in equilibrium is called what?
a) Freezing point
b) Boiling point
c) Triple point
d) Double point
View Answer
Explanation: The solid liquid and gaseous water co exist at a point called as triple point of water. This point is used to measure the units of temperature.
8. When water molecule stay close to each other it is called as?
a) Adhesion
b) Cohesion
c) Inhibition
d) Capillary action
View Answer
Explanation: Due to the collective action of hydrogen bonds between water molecules, they stay close to each other. This property is called as cohesion.
Sanfoundry Global Education & Learning Series – Food Chemistry.
To practice all areas of Food Chemistry, here is complete set of Multiple Choice Questions and Answers.