CMSP Fundamental Knowledge of Science 2 — Questions and Answers
Question 1: Which gas law states that at constant temperature, the pressure and volume of a gas are inversely proportional?
- Charles's Law
- Boyle's Law (Correct answer)
- Gay-Lussac's Law
- Avogadro's Law
Correct answer: Boyle's Law
Boyle's Law states that P₁V₁ = P₂V₂ at constant temperature, meaning pressure and volume are inversely proportional.
Question 2: In a mine atmosphere, which property of methane makes it particularly dangerous compared to air?
- Methane is denser than air and settles at floor level
- Methane is lighter than air and accumulates near the roof (Correct answer)
- Methane is highly soluble in water and condenses in low areas
- Methane has a lower ignition temperature than carbon monoxide
Correct answer: Methane is lighter than air and accumulates near the roof
Methane (CH₄) has a specific gravity of ~0.55, making it lighter than air so it accumulates at roof level in mine entries.
Question 3: What is the primary chemical reaction that produces heat during spontaneous combustion of coal?
- Hydration of calcium oxide
- Oxidation of carbon compounds at low temperature (Correct answer)
- Reduction of sulfur dioxide
- Pyrolysis of methane
Correct answer: Oxidation of carbon compounds at low temperature
Spontaneous combustion results from slow oxidation of carbon in coal releasing heat faster than it dissipates, eventually reaching ignition temperature.
Question 4: Which unit correctly expresses the concentration of a gas contaminant in a mine atmosphere?
- mg/m² (milligrams per square meter)
- ppm (parts per million by volume) (Correct answer)
- Pa (pascals)
- cd/m² (candelas per square meter)
Correct answer: ppm (parts per million by volume)
Gas contaminant concentrations in mine air are expressed as ppm (parts per million by volume) or percent by volume for higher concentrations.
Question 5: A rock sample has a mass of 250 g and a volume of 100 cm³. What is its density?
- 0.4 g/cm³
- 2.5 g/cm³ (Correct answer)
- 25 g/cm³
- 350 g/cm³
Correct answer: 2.5 g/cm³
Density = mass ÷ volume = 250 g ÷ 100 cm³ = 2.5 g/cm³.
Question 6: Silica dust in mines primarily causes health damage by which mechanism?
- Alkaline pH damage to alveoli
- Chronic inflammation and fibrosis triggered by crystalline silica particles (Correct answer)
- Blocking of oxygen transport in red blood cells
- Neurological toxicity from silica ions absorbed into bloodstream
Correct answer: Chronic inflammation and fibrosis triggered by crystalline silica particles
Crystalline silica particles trigger persistent macrophage activation and inflammatory cytokine release, leading to progressive pulmonary fibrosis (silicosis).
Question 7: Which principle explains why ventilation air naturally flows from higher pressure areas to lower pressure areas in a mine?
- Pascal's principle of fluid pressure transmission
- The pressure gradient drives fluid (air) from high to low pressure (Correct answer)
- Bernoulli's principle of energy conservation in flowing fluid
- Archimedes' principle of buoyancy
Correct answer: The pressure gradient drives fluid (air) from high to low pressure
Air moves from high-pressure to low-pressure regions due to the pressure gradient force, which is the fundamental driver of airflow in mine ventilation.
CMSP Fundamental Knowledge of Science 2
Which gas law states that at constant temperature, the pressure and volume of a gas are inversely proportional?