Explanation

• As you move down a group in the periodic table, the atomic size increases.
• This means that the outermost electrons are farther away from the nucleus, making it easier for the atom to gain an extra electron.
• As a result, the electron affinity decreases down a group.

Explanation

• In 1869, Dmitri Mendeleev proposed his periodic law, which states: "When the elements are arranged in order of increasing atomic mass, certain sets of properties recur periodically."
• This law allowed him to create the first periodic table, where elements were arranged in a logical order based on their atomic masses and chemical properties.

Explanation

Root hairs are thin, hair-like structures that extend from the roots of plants, increasing the surface area for absorption of water and nutrients from the soil. They play a crucial role in:

• Absorbing water and minerals
• Anchoring the plant in the soil
• Facilitating the uptake of nutrients

Explanation

• Mercury is a silvery-white liquid metal that was traditionally used in clinical thermometers due to its high coefficient of expansion.
• It allowing for accurate temperature measurements.

Explanation

Digital TVs do not emit Y or X-rays.

They emit electromagnetic radiation in the form of radio waves to transmit audio and video signals.

X-rays are a form of ionizing radiation used in medical imaging and other specialized applications,

but they are not produced by digital TVs.

Explanation

Carbon Dioxide is responsible for fermentation.

During fermentation, microorganisms like yeast convert sugars into alcohol and carbon dioxide as byproducts.

Explanation

Facilitated diffusion is a type of passive transport that uses carrier proteins to move specific substances across the cell membrane without energy input.

This process allows cells to regulate the movement of essential molecules, like sugars and amino acids, into or out of the cell.

Explanation

Radioactive isotopes, such as carbon-14 and uranium-238, decay at a steady rate.

It allowing scientists to measure the age of fossils and rocks.

This technique is known as radiometric dating.

Explanation

The nucleus, which consists of protons and neutrons.

It is incredibly dense and occupies a very small volume compared to the extra-nuclear part (electrons).

However, the nucleus contains most of the atom's mass due to the significant mass of protons and neutrons.

Explanation

Cotton is a natural fiber that contains a very high percentage of cellulose, typically around 95%.

Cellulose is a polysaccharide (a long chain of glucose molecules) that provides strength, structure, and durability to plant cell walls.

Cotton is one of the purest forms of cellulose, making it a valuable resource for textile production.