Fundamental Knowledge of Science Flashcards

Which gas law states that at constant temperature, the pressure and volume of a gas are inversely proportional?

Answer: Boyle's Law

Boyle's Law states that P₁V₁ = P₂V₂ at constant temperature, meaning pressure and volume are inversely proportional.

In a mine atmosphere, which property of methane makes it particularly dangerous compared to air?

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.

What is the primary chemical reaction that produces heat during spontaneous combustion of coal?

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.

Which unit correctly expresses the concentration of a gas contaminant in a mine atmosphere?

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.

A rock sample has a mass of 250 g and a volume of 100 cm³. What is its density?

Answer: 2.5 g/cm³

Density = mass ÷ volume = 250 g ÷ 100 cm³ = 2.5 g/cm³.

Silica dust in mines primarily causes health damage by which mechanism?

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).

Which principle explains why ventilation air naturally flows from higher pressure areas to lower pressure areas in a mine?

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.