Question
Where do hydrogen bonds form?
A. Between the slight negative charge of hydrogen and slight positive charge of oxygen within a water molecule
B. Between the slight positive charge of hydrogen and slight negative charge of oxygen within a water molecule
C. Between the slight positive charge of hydrogen and slight negative charge of oxygen in different water molecules
D. Between the slight negative charge of hydrogen and slight positive charge of oxygen in different water molecules
Answer/Explanation
Ans: C
Question
What are linked by hydrogen bonds?
A. Hydrogen and oxygen within a water molecule
B. Phosphate and sugar within a DNA molecule
C. Base and sugar between DNA nucleotides
D. Hydrogen and oxygen in different water molecules
Answer/Explanation
Ans: D
Question
Between which atoms do hydrogen bonds form in water?
A. Oxygen and hydrogen atoms in the same water molecule
B. Oxygen and hydrogen atoms in different water molecules
C. Hydrogen atoms in the same water molecule
D. Oxygen atoms of different water molecules
▶️Answer/Explanation
Markscheme
Ans: B
Hydrogen bonds form between the hydrogen atoms of one water molecule and the oxygen atom of another water molecule. Each water molecule can form 2 hydrogen bonds between oxygen and the two hydrogen atoms in the molecule.
Question
What property of water accounts for its usefulness as a coolant in sweat?
High specific heat capacity
High latent heat of vaporization
High boiling point
High melting point
Answer/Explanation
Ans: B
Question
The diagram shows water molecules.
Which property of water is not illustrated?
A. Cohesion
B. Dipolarity
C. Hydrogen bonding
D. Adhesion
▶️Answer/Explanation
D
Question
The diagram shows the elements present in two organic molecules, W and X.
Which molecules could W and X be?
▶️Answer/Explanation
C
Question
What is the benefit to living organisms that water has a high specific heat capacity?
A. Heat can be lost from the skin when sweat evaporates.
B. Aquatic environments do not have a great fluctuation in their temperature.
C. The amount of heat stored by water is highly predictable.
D. It allows water to be a solvent for chemical reactions at body temperature.
▶️Answer/Explanation
B
Question
What is a property of water?
A. Water has a low specific heat capacity so large increases in heat energy cause a small temperature change.
B. Water is an excellent solvent for non-polar substances.
C. Covalent bonds between adjacent water molecules are responsible for its unique properties.
D. Water molecules are highly cohesive which is important for transport in xylem.
▶️Answer/Explanation
D