Explanation

• Wilhelm Conrad Rontgen discovered X-rays
• He was discovered on 8 November 1895.
• He got the Nobel Prize in Physics in 1901.

Additional questions

• The penetrating power of X-rays depends on their frequency

Last updated 26-07-2026 by NA

Explanation

• Polyethylene (PE) is one of the most widely used plastics in the world.
• Because it is lightweight, durable, chemically resistant, and relatively inexpensive.
• It is commonly used to make plastic bags, bottles, containers, packaging films, and household products.
• Polyethylene is produced from ethylene (ethene) through polymerization.

Last verified on 05-10-2026

Explanation

• Nitrous oxide, commonly known as laughing gas.
• It is a colorless, non-flammable gas used in medicine.
• Nitrous oxide (N₂O) causes temporary laughing and relaxation.

Additional information:

• Nitrous oxide was discovered by Joseph Priestley in 1772.

Last verified on 18-01-2026

Explanation

• The atomic number of hydrogen is 1.
• It is the first element on the periodic table. 
• Named by: Antoine Lavoisier (1783)
• Atomic mass: 1.00784 u
• Appearance: Colorless gas
• Symbol: H
• Protons: 1
• Electrons: 1

Last updated 26-07-2026 by NA

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