Cambridge Lower Secondary Science Stage 9: Student's Book>Chapter 5 - The Periodic Table>End of Chapter Review>Q 11

MEDIUM

Lower Secondary Stage 9

IMPORTANT

Earn 100

An aluminium atom has the atomic number 13 and a mass number of 27.

State what period and group aluminium is in the Periodic Table. Explain how you can use its electron structure to work this out.

Important Questions on The Periodic Table

EASY

Lower Secondary Stage 9

IMPORTANT

Cambridge Lower Secondary Science Stage 9: Student's Book>Chapter 5 - The Periodic Table>End of Chapter Review>Q 12

Use what you know about how electrons are arranged in atoms to explain why elements in the same group share similar properties.

MEDIUM

Lower Secondary Stage 9

IMPORTANT

Cambridge Lower Secondary Science Stage 9: Student's Book>Chapter 5 - The Periodic Table>End of Chapter Review>Q 13

The model of the atom has changed over time. Explain why this is so.

MEDIUM

Lower Secondary Stage 9

IMPORTANT

Cambridge Lower Secondary Science Stage 9: Student's Book>Chapter 5 - The Periodic Table>End of Chapter Review>Q 14

The gold foil experiment performed by Rutherford and his team was repeated many times by them and by other scientists. Suggest why this is important.

MEDIUM

Lower Secondary Stage 9

IMPORTANT

Cambridge Lower Secondary Science Stage 9: Student's Book>Chapter 5 - The Periodic Table>End of Chapter Review>Q 15

The table shows the boiling points of some of the Group 8 elements.

Name	Boiling point( $° C$ )
Helium	$- 272$
Neon	$- 249$
Argon	$- 189$
Krypton
Xenon	$- 112$
Radon	$- 71$

a) Describe the trend in data.

b) Estimate the boiling point of Krpton.

MEDIUM

Lower Secondary Stage 9

IMPORTANT

Cambridge Lower Secondary Science Stage 9: Student's Book>Chapter 5 - The Periodic Table>End of Chapter Review>Q 16

Rajeev read on a website that 'Mendeleev invented the periodic table we use today'. Discuss the arguments for and against this statement.