Cambridge Secondary (7-9). Stage 9. MCE Science. Student Book - Unit 5: Chemical Bonding and Structure of Materials

Why does the impact of CFCs on the environment affect the whole world?

Why is neon unreactive?

How do atoms obtain a stable electronic configuration?

Helium has two electrons in its outer shell. Will it form covalent bonds with oxygen? Why?

In pairs, share your answer.

What is a covalent bond?

Describe how two chlorine atoms form a covalent bond.

1 Choose one of the following metals: calcium, magnesium, sodium or potassium. Draw a dot-and-cross diagram to show an atom of the chosen element.

2 Choose one of the following non-metals: fluorine, chlorine or oxygen. Draw a dot-and-cross diagram to show an atom of the chosen element.

3 Illustrate how an ionic bond is formed between the metal and the non-metal to create an ionic compound. Note that some of the ionic compounds may require two atoms of the metal or non-metal.

Share your answers with the class.

What is a negative ion called?

How is an ionic bond formed?

When sodium reacts with oxygen, the ionic compound sodium oxide is formed. How many electrons does each oxygen atom gain to become a negatively charged oxide ion?

Diamonds and graphite are both made of carbon atoms. Why are their properties so different?

In pairs, share your answer.

Why do atoms react with one another?

The electronic configuration of oxygen is 2, 6. Circle all the statements that are correct about the oxygen atom.

Which of the following have covalent bonds? Tick (✓) the two correct answers.

State whether each statement applies to a covalent bond or an ionic bond.

A compound is formed when a metal bonds with a non-metal.

State whether each statement applies to a covalent bond or an ionic bond.

Two atoms share electrons.

State whether each statement applies to a covalent bond or an ionic bond.

Two atoms of non-metals join.

State whether each statement applies to a covalent bond or an ionic bond.

The compound can be dissolved in water and conduct electricity.

State whether each statement applies to a covalent bond or an ionic bond.

Atoms gain and lose electrons.

State whether each statement applies to a covalent bond or an ionic bond.

A compound is formed when a non-metal bonds with another non-metal.