Chemistry S1 Exam 2024-2025

Front

Why does the atomic radius decrease as you move across a period?

Back

Because protons are being added, which increases the positive charge in the nucleus, pulling electrons closer.

Front

What is the atomic number of an element?

Back

The atomic number is the number of protons in the nucleus of an atom, which determines the element's identity.

Front

How do covalent bonds form?

Back

Covalent bonds form by sharing valence electrons between atoms.

Front

What is an isotope?

Back

An isotope is a variant of a chemical element that has the same number of protons but a different number of neutrons.

Front

What is the nucleus of an atom?

Back

The nucleus is the central region of an atom where protons and neutrons are located.

Front

What is the charge of a proton?

Back

A proton has a positive charge.

Front

What is the charge of a neutron?

Back

A neutron has no charge (it is neutral).

Front

What is the charge of an electron?

Back

An electron has a negative charge.

Front

What is the significance of valence electrons?

Back

Valence electrons are the outermost electrons of an atom and are involved in forming bonds with other atoms.

Front

What is the difference between ionic and covalent bonds?

Back

Ionic bonds involve the transfer of electrons, while covalent bonds involve the sharing of electrons.