General Science/Everyday Science MCQs
Topic Notes: General Science/Everyday Science
MCQs and preparation resources for competitive exams, covering important concepts, past papers, and detailed explanations.
Plato
- Biography: Ancient Greek philosopher (427–347 BCE), student of Socrates and teacher of Aristotle, founder of the Academy in Athens.
- Important Ideas:
- Theory of Forms
- Philosopher-King
- Ideal State
71
What is the mass of one mole of Carbon-12 atoms?
Answer:
12 grams
The mole is defined such that one mole of Carbon-12 has a mass of exactly 12 grams. This is known as the molar mass.
72
At constant pressure, the volume of a gas is directly proportional to its absolute temperature. This is known as:
Answer:
Charles's Law
Charles's Law states that for a fixed mass of gas at constant pressure, $V/T = k$. This means volume increases linearly with temperature (measured in Kelvin).
73
Antibiotics are powerful medicines, but they are only effective against which group of pathogens?
Answer:
Bacteria
Antibiotics work by targeting specific biological structures in bacteria, such as the cell wall or bacterial ribosomes. Because viruses lack these structures and rely on host cells for replication, antibiotics have no effect on viral infections.
74
Which type of solid is held together by a 'sea of delocalized electrons'?
Answer:
Metallic solid
In metallic bonding, metal atoms release their valence electrons into a common pool. These delocalized electrons move freely throughout the structure, which explains conductivity and malleability.
75
What is the process called when a substance changes directly from a solid to a gas?
Answer:
Sublimation
Sublimation is the transition of a substance directly from the solid to the gas phase without passing through the intermediate liquid phase. Common examples include dry ice (solid $CO_2$) and naphthalene balls.
76
The MMR vaccine provides protection against which three diseases?
Answer:
Measles, Mumps, Rubella
The MMR vaccine is a combination vaccine that protects against Measles (a respiratory virus with a rash), Mumps (swelling of salivary glands), and Rubella (German measles). It is a standard part of childhood immunization schedules.
77
Which subatomic particle is the lightest?
Answer:
Electron
The mass of an electron is approximately $9.11 imes 10^{-31}$ kg, which is about 1840 times smaller than the mass of a proton or neutron.
78
How do 'Antiviral' drugs differ from 'Antibiotics'?
Answer:
Antivirals inhibit the development of viruses, while antibiotics kill bacteria
Antibiotics kill bacteria or stop them from growing. Antivirals do not 'kill' viruses (as viruses aren't technically alive); instead, they interfere with the virus's ability to enter a host cell, replicate its genetic material, or exit the cell.
79
How is the bacterium 'Vibrio cholerae', which causes Cholera, typically transmitted to humans?
Answer:
Through contaminated food and water
Cholera is a classic waterborne disease. The bacteria are shed in the feces of infected people and can contaminate water supplies or food handled with poor hygiene. Ingesting this contaminated material leads to severe intestinal infection and rapid dehydration.
80
Why is it important to complete a full course of antibiotics prescribed by a doctor?
Answer:
To prevent the bacteria from developing antibiotic resistance
If a patient stops taking antibiotics early, the weaker bacteria might be killed, but the more resilient ones may survive and multiply. These surviving bacteria can develop resistance to the drug, making future infections much harder to treat.