BMAT Knowledge 5 — Questions and Answers
Question 1: What is the molar mass of calcium carbonate (CaCO₃)?
- 56 g/mol
- 84 g/mol
- 100 g/mol (Correct answer)
- 116 g/mol
Correct answer: 100 g/mol
Molar mass = Ca(40) + C(12) + 3×O(16) = 40 + 12 + 48 = 100 g/mol.
Question 2: In a parallel circuit with two identical 10 Ω resistors connected to a 20 V supply, what is the total current drawn?
- 1 A
- 2 A
- 4 A (Correct answer)
- 0.5 A
Correct answer: 4 A
Two 10 Ω resistors in parallel give total resistance 5 Ω; total current = V/R = 20/5 = 4 A.
Question 3: Which hormone is secreted by the pancreas to lower blood glucose levels?
- Glucagon
- Adrenaline
- Insulin (Correct answer)
- Cortisol
Correct answer: Insulin
Insulin is released by beta cells of the pancreas and stimulates cells to absorb glucose from the bloodstream.
Question 4: A car decelerates uniformly from 30 m/s to rest over 150 m. What is its deceleration?
- 1 m/s²
- 2 m/s²
- 3 m/s² (Correct answer)
- 5 m/s²
Correct answer: 3 m/s²
Using v² = u² + 2as: 0 = 900 + 2a(150), so a = −3 m/s², deceleration = 3 m/s².
Question 5: In the reaction CH₄ + 2O₂ → CO₂ + 2H₂O, methane is acting as a:
- Oxidising agent
- Reducing agent (Correct answer)
- Catalyst
- Base
Correct answer: Reducing agent
Methane is oxidised (carbon goes from −4 to +4), so it acts as the reducing agent by donating electrons.
Question 6: Which part of the human brain controls involuntary functions such as heart rate and breathing?
- Cerebrum
- Cerebellum
- Medulla oblongata (Correct answer)
- Hypothalamus
Correct answer: Medulla oblongata
The medulla oblongata, located in the brainstem, regulates vital autonomic functions including heart rate and respiration.
Question 7: What is the resultant force on an object moving at constant velocity?
- Equal to its weight
- Equal to friction
- Zero (Correct answer)
- Equal to its momentum
Correct answer: Zero
Newton's first law states that a constant (non-zero) velocity means the net force on the object is zero.
BMAT Knowledge 5
What is the molar mass of calcium carbonate (CaCO₃)?