Radon is used as a tracer in medical research because it

• A. is monatomic
• B. is radioactive
• C. is a noble gas
• D. has a complete valence shell

Which of the following is a unique property of water compared to other liquids?

• A. It is a poor solvent
• B. It does not evaporate
• C. It expands when freezing
• D. It has a low heat capacity

When NH₄Cl(s) is dissolved in water, the container feels cold to touch. This implies

• A. The process is endothermic
• B. The process is exothermic
• C. NH₄Cl forms a saturated solution
• D. NH₄Cl is highly soluble in water

A consequence of global warming is

• A. air pollution
• B. water pollution
• C. increased humudity
• D. flooding

In the diagram below, the gas produced is

• A) NO
• B) NO2
• C) N2O
• D) N2O4

This compound exhibits ionic bonding

• A) H₂O
• B) H₂
• C) KCl
• D) NH₃

An acidic salt has

• A. double anions in its aqueous solution
• B. a single cation in its aqueous solution
• C. hydrogen ions in its aqueous solution
• D. hydrogen atoms in its aqueous solution

In a water body, too much sewage leads to

• A) a decrease in the temperature of the water which cause in death of aquatic animals
• B) an increase in the number of aquatic animals in the water
• C) an increase in the bacterial population which reduces the level of oxygen in the water
• D) a decrease in the bacterial population which increases the level of oxygen in the water

Three drops of a 1.0 mol dm^-3 solution of NaOH are added to 20 cm³of a solution of pH 8.4. The pH of the resulting solution will be

• A. Close to that of pure water
• B. Unaltered
• C. Greater than 8.4
• D. Less than 8.4

Which of the following are structural isomers?

• A. propanoic acid and propan-1, 2-diol
• B. Propanal and propanone
• C. Ethanoic acid and propanoic acid
• D. Ethan-1, 2-diol and ethanoic acid