Explanation

• Geology means the study of the Earth.
• It is also called Earth Science or Geoscience.
• Geology studies the formation, structure, composition, and history of Earth.
• It also examines the processes acting on Earth, such as earthquakes, volcanoes, and erosion.
• A person who studies geology is called a geologist.

Last verified on 15-09-2026

Explanation

• The smallest unit of matter is an atom.

Structure of an Atom

• Nucleus: The central part made of heavy protons and neutrons.
• Electrons: Tiny, light particles that circle the nucleus.
• Protons: Particles with a positive charge.
• Neutrons: Particles with no electrical charge

Explanation

• Position: 2nd planet from the Sun.
• Distance: About 108 million km from the Sun.
• Order: Mercury → Venus → Earth.
• Temperature: Hottest planet in the Solar System.
• Reason: Thick atmosphere traps heat through the greenhouse effect.

Explanation

• Hydrogen and helium are the two lightest gases.
• Helium is the second most abundant element in the universe, after hydrogen.
• Helium has monatomic molecules.
• It is the lightest of all gases except hydrogen.
• Hydrogen is the lightest gas known.
• It provides the maximum lift for balloons due to its very low density.

Last updated question 17-02-2026

Explanation

• Discoverer: Alexander Fleming
• Year of discovery: 1928
• Place: St. Mary's Hospital, London
• First patient treated with penicillin: Albert Alexander
• Date of first treatment: 12 February 1941

Last verified on 14-09-2026