BMST Atomic Structure and Bonding 5

Question 1

What does the principal quantum number (n) describe?

Accepted Answer

The energy level or shell of an electron

Answer

The principal quantum number n indicates the main energy level (shell) where an electron is found.

Question 2

A coordinate covalent bond differs from a regular covalent bond because:

Accepted Answer

Both electrons are contributed by the same atom

Answer

In a coordinate (dative) covalent bond, one atom donates both electrons of the shared pair.

Question 3

Which element has atomic number 6 and is the basis of organic chemistry?

Accepted Answer

Carbon

Answer

Carbon has atomic number 6 and its ability to form four bonds makes it the backbone of organic molecules.

Question 4

When an atom gains an electron, it becomes a(n):

Accepted Answer

Anion

Answer

Gaining an electron gives the atom a net negative charge, making it a negatively charged ion called an anion.

Question 5

Which subshell fills first: 3d or 4s?

Accepted Answer

4s fills first

Answer

According to the Aufbau principle, 4s has lower energy than 3d and fills before it in electron configuration.

BMST - Basic Math and Science Test Practice Test