Quiz: LFS103 Bioscience Week 1 — 11 questions

1. What percentage of the course grade is assigned to Task 2, the mid-semester exam?

A. 20% of the course grade

B. 40% of the course grade

C. 30% of the course grade

D. 10% of the course grade

Answer: (A)

Explanation

Task 2 is the mid-semester exam and contributes 20% of the overall course grade. The 40% weighting belongs to Task 1 and the final exam, not to Task 2.

2. A student scores below 14 on the Maths Diagnostic. What action is recommended?

A. Repeat the diagnostic during the final examination

B. Seek support from a STEM Learning Adviser

C. Withdraw from the course before the next assessment

D. Request that the diagnostic be added to the course grade

Answer: (B)

Explanation

Students below 14 are advised to seek help from a STEM Learning Adviser, while the diagnostic itself does not count toward the grade. Adding it to the assessment or withdrawing is not part of the stated guidance.

3. Which description correctly compares the shapes and volumes of solids, liquids, and gases?

A. A solid has neither property, a liquid has fixed shape, and a gas has fixed shape and volume

B. A solid has fixed shape, a liquid has fixed shape and volume, and a gas has fixed volume

C. A solid has fixed shape and volume, a liquid has fixed volume, and a gas has neither

D. A solid has fixed volume, a liquid has neither property, and a gas has fixed shape

Answer: (C)

Explanation

Solids retain both their shape and volume, liquids retain volume but take the shape of their container, and gases retain neither. The other descriptions incorrectly assign fixed shapes or volumes to fluids.

4. Caramelisation of sugar is classified as which type of change?

A. A physical change because browning does not alter composition

B. A mixture-forming change because the sugar dissolves in moisture

C. A physical change because the sugar merely changes state

D. A chemical change because new compounds form

Answer: (D)

Explanation

Caramelisation is a chemical change because sugar breaks down and reforms into new compounds, producing the brown color. A physical change would not create substances with new chemical structures.

5. Which statement distinguishes a physical change from a chemical change?

A. A physical change requires heating, whereas a chemical change occurs without energy transfer

B. A physical change forms no new substances, whereas a chemical change forms new substances

C. A physical change forms new compounds, whereas a chemical change preserves the original substances

D. A physical change changes chemical structure, whereas a chemical change changes physical appearance

Answer: (B)

Explanation

Physical changes do not produce new substances, while chemical changes involve altered chemical structure and the formation of new substances. Heating and appearance can occur in either type of change and therefore do not define the distinction.

6. Which description correctly identifies sodium on the periodic table?

A. Na, in Period 2 and Group 7A, the halogen group

B. Na, in Period 3 and Group 1A, the alkali-metal group

C. S, in Period 3 and Group 1A, the alkali-metal group

D. Na, in Period 1 and Group 3A, the boron group

Answer: (B)

Explanation

Sodium uses the symbol Na and is located in Period 3 and Group 1A, also called Group 1 or the alkali metals. The symbol S represents sulfur, while the alternative periods and groups do not identify sodium.

7. Which chemical symbol represents calcium?

A. Fe

B. Ca

C. Cu

D. C

Answer: (B)

Explanation

Calcium is represented by the symbol Ca. C represents carbon, Cu represents copper, and Fe represents iron.

8. Which property most clearly distinguishes typical non-metals from typical metals?

A. They have higher density and conduct electricity efficiently

B. They have lower density and conduct electricity poorly

C. They contain more protons and have larger atomic nuclei

D. They are generally solid and have a metallic luster

Answer: (B)

Explanation

Non-metals typically have low density and poor electrical conductivity, while most metals are solid and conductive. The second choice reverses the usual conductivity and density pattern associated with these groups.

9. An unknown element is a low-density liquid at room temperature and does not conduct electricity. How should it be classified?

A. As a non-metal based on its physical properties

B. As a non-metal because all non-metals are gases at room temperature

C. As a metal because it remains liquid at room temperature

D. As a metal because low density indicates metallic behavior

Answer: (A)

Explanation

The combination of low density, liquid state, and lack of electrical conductivity matches the characteristic properties of a non-metal. A liquid non-conductive element is not classified as a metal merely because of its state.

10. Which set correctly matches each subatomic particle with its electric charge?

A. Electron: 0; proton: 1+; neutron: 1−

B. Electron: 1+; proton: 1−; neutron: 0

C. Electron: 1−; proton: 1+; neutron: 0

D. Electron: 1−; proton: 0; neutron: 1+

Answer: (C)

Explanation

Electrons carry a negative charge, protons carry a positive charge, and neutrons are neutral. The second choice incorrectly reverses the charges of electrons and protons.

11. An atom has 17 protons in its nucleus. What does its atomic number indicate?

A. Its atomic number is 1, because the nucleus contains positive charge

B. Its atomic number is 17, identifying the element

C. Its atomic number is 34, counting protons and electrons together

D. Its atomic number is 18, based on the number of occupied shells

Answer: (B)

Explanation

Atomic number is defined by the number of protons in the nucleus, so an atom with 17 protons has atomic number 17. Counting electrons or shells does not determine atomic number.