Explanation

A catalyst speeds up a chemical reaction without being consumed in the process.

It lowers the activation energy, allowing the reaction to occur faster.

Explanation

The Arrhenius theory (1887) defines:

Acids: Substances that dissociate in water to produce H⁺ ions (protons), such as:

HCl → H⁺ + Cl⁻

Bases: Substances that dissociate in water to produce OH⁻ ions (hydroxide ions), such as:

NaOH → Na⁺ + OH⁻

Explanation

Ionization energy is the minimum energy needed to remove one electron from a gaseous atom in its ground state.

It reflects how tightly an electron is held — higher ionization energy means stronger attraction to the nucleus.

Explanation

Meiosis reduces the chromosome number by half, forming haploid cells (e.g., gametes).

This ensures that during fertilization, the diploid number is restored in the offspring.

Explanation

Chemical equilibrium occurs when the forward and reverse reactions occur at the same rate.

At this point, the concentrations of reactants and products remain constant, not necessarily equal.

Explanation

When light passes from a rarer to a denser medium, its speed and wavelength decrease, but the frequency stays the same.

This is because the source determines frequency, and it doesn’t change with medium.

Explanation

First law of motion is also called the Law of Inertia.

It states that an object will stay at rest or move with constant velocity unless an external force changes its state.

Explanation

A hypothesis is a testable and specific explanation for a scientific observation or question.

It can be confirmed or rejected through experiments and data collection.

Explanation

Blood carries oxygen from the lungs and nutrients from the digestive system to all body cells.

It also removes carbon dioxide and waste products, helping maintain overall body function.

Explanation

Amoeba is a unicellular organism, meaning it consists of only one cell.

It performs all life processes like movement, feeding, and reproduction within that single cell.