chemistry topic one : key concepts and atomic structure

What are the three subatomic particles?

Protons, neutrons, and electrons.

What is the charge of a proton?

$$+1$$

What is the charge of a neutron?

$$0$$

What is the charge of an electron?

$$-1$$

Where are protons and neutrons found?

In the nucleus.

Where are electrons found?

In shells around the nucleus.

What is the relative mass of a proton?

$$1$$

What is the relative mass of a neutron?

$$1$$

What is the relative mass of an electron?

Approximately $\frac{1}{1836}$

What is atomic number?

The number of protons.

What is mass number?

The number of protons plus neutrons.

How do you calculate the number of neutrons?

Mass number minus atomic number.

What is an isotope?

Atoms of the same element with the same number of protons but different numbers of neutrons.

Why do isotopes have similar chemical properties?

They have the same electronic configuration.

What is electronic configuration?

The arrangement of electrons in shells.

How many electrons fit in the first shell?

$$2$$

How many electrons fit in the second shell?

$$8$$

How many electrons fit in the third shell for the first 20 elements?

$$8$$

What is an ion?

A charged particle formed when an atom gains or loses electrons.

What happens when an atom loses electrons?

It becomes positively charged.

What happens when an atom gains electrons?

It becomes negatively charged.

How do you calculate relative atomic mass?

Multiply each isotope mass by its abundance, add the results, and divide by the total abundance.