Unit-4: Water Chemistry Flashcards
What is the chemical formula of water?
H₂O, composed of two hydrogen atoms covalently bonded to one oxygen atom.
What gives water its high boiling and melting points?
Extensive hydrogen bonding.
Why is water called a ‘universal solvent’?
Due to its polarity and ability to dissolve many ionic and polar substances.
Why is water colorless with a faint blue tint?
Weak absorption of light at around 750 nm wavelength.
Name two key physical properties of water.
High surface tension and low thermal conductivity.
What is the charge distribution in a water molecule?
Oxygen is partially negative, and hydrogen is partially positive.
What causes water molecules to aggregate?
Hydrogen bonding.
What is potable water?
Water that is safe for human consumption.
Define brackish water.
Water with salinity between freshwater and seawater.
What is grey water?
Domestic wastewater with lower nitrogen and phosphorus levels than black water.
What is black water?
Water contaminated with feces or urine.
What is water pollution?
Contamination of water bodies, affecting their physical, chemical, or biological properties.
What are the two chief sources of water pollution?
Point source and non-point source pollution.
Define eutrophication.
Excessive nutrients in water leading to algae blooms and oxygen depletion.
What is a common cause of chemical water pollution?
Industrial discharge of metals, solvents, and pesticides.
What is surface water pollution?
Pollution of rivers, lakes, and oceans by hazardous substances.
How does groundwater pollution occur?
Pesticides and chemicals leach into aquifers through rainwater.
What is oil spillage pollution?
Oil spills in water that harm marine life and birds.
What does BOD5 measure?
The amount of oxygen needed by microorganisms to break down organic material in 5 days.
What is the acceptable pH range for treated wastewater?
Between 5 and 9.
Name three key parameters for water quality.
COD, TSS, and Total Nitrogen.
Name one method to control industrial wastewater pollution.
Recycling and reuse of water.
How can farmers reduce agricultural runoff pollution?
By minimizing chemical usage and manuring farm waste.
What is biomagnification?
Accumulation of non-biodegradable chemicals in the food chain.
