Ions

Ions

Poll

Would you rather get stuck at all red lights in traffic or have incredibly slow internet forever?

• Red Lights

• No Internet

Match

Match the following subatomic particles to their charge.

• Proton

• Neutron

• Electron

Positive

Neutral

Negative

• Positive

• Neutral

• Negative

Multiple Choice

If an atom has 2 protons, 3 neutrons, and 2 electrons, what is its overall charge?

• +2

• -2

• Neutral

Fill in the Blanks

What is the name for the outside shell of an atom.

Hint: It starts with V.

Recap

• Valency = number of electrons an atom needs to gain, lose, or share to get a full outer shell.

• Example: Sodium (Na) has valency 1 (one electron away from full shell).

• So far, we have said valency is just a number - but it actually shows if the atom will become positively or negatively charged.

What is an ion?

When a neutral atom gains or loses electrons, the number of protons stays the same. The balance between positive and negative charges is lost. The result is a particle with an overall positive or negative charge. This is called an ion.

What is an ion?

An ion is an atom that has gained or lost electrons and now has an electric charge.

• If it loses electrons, it becomes a positive ion (called a cation).

• If it gains electrons, it becomes a negative ion (called an anion).

Multiple Choice

What is an ion?

• An atom with a full outer shell

• An atom that has gained or lost electrons and has a charge

• An atom with equal protons and neutrons

• A molecule made of two atoms

Gaining Electrons

​This is nitrogen.

Nitrogen has an atomic number of 7, so it has 2 electrons in its first shell and 5 in its valence shell.

What is the easiest way for it to reach an octet (8 electrons)?

Gaining Electrons

​Negative ions form when a neutral atom gains electrons, so it has more electrons than protons. They are called anions.

For example, N^3- is a nitrogen ion that has three extra electrons compared to the neutral nitrogen atom.

Gaining Electrons

Losing Electrons

​This is sodium.

Sodium has an atomic number of 11, so it has 2 electrons in its first shell, 8 in its second shell, and 1 in its valence shell.

What is the easiest way for it to reach an octet (8 electrons)?

Losing Electrons

Positive ions form when a neutral atom loses electrons, so it has more protons than electrons. They are called cations.

For example, Na¹⁺ is a sodium ion that is missing one electron compared to the neutral sodium atom.

Losing Electrons

​Gain electrons = negative charge
Lose electrons = positive charge

Multiple Choice

If an atom loses 2 electrons, what charge will its ion have?

• -2

• +2

• 0

• -1

Multiple Choice

Chlorine has a valency of 1 and gains an electron. What is the charge on the ion?

• +1

• -1

• 0

• +2

Multiple Choice

Sodium (Na) has a valency of 1. When it forms an ion, what is the charge and why?

• Na⁺ because it loses 1 electron

• Na⁻ because it gains 1 electron

• Na²⁺ because it loses 2 electrons

• Na⁻ because it loses 1 electron

Multiple Choice

A lithium ion has 3 protons and 2 electrons. It forms when a neutral lithium atom loses one electron.

• Negative Ion

• Positive Ion

• I'm not sure

Multiple Choice

Determine the option that correctly completes the sentence.

A calcium ion is represented by the symbol: Ca²⁺.

The "2+" superscript tells us that this ion formed when a neutral calcium atom:

• Lost one electron

• Lost two electrons

• Gained one proton

• Gained two protons

Multiple Select

Which statements about O^2- are correct?

• It is an oxygen ion

• Its overall charge is negative

• It has gained two electrons

• It has lost two electrons

Multiple Choice

An atom has 11 protons, 11 neutrons and 10 electrons.

What this is an example of?

• A negative ion

• A neutrol atom

• A positive ion

• More information is needed

• I'm not sure