Crack the code. Write down the element symbols to find the hidden words. Element Symbol Chlorine _____ Oxygen _____ Carbon _____ Potassium _____

Crack the code. Write down the element symbols to find the hidden words. Element Symbol Chlorine Cl Oxygen O Carbon C Potassium K Code: Cl O C K A chemical symbol is a notation of one or two letters representing a chemical element.Symbols are used commonly for the representation of elements in the modern periodic table since the names of elements can be long and complex to use. Chemical formulae and equations are also depicted using the chemical symbols of the constituent elements. Elements are pure substances which are the basic unit of matter and cannot be broken down into two or simpler substances by any means.

EASY

Lower Secondary Stage 8

IMPORTANT

Earn 100

Look at the diagram. It shows a sealed gas syringe.

Use your knowledge of particle theory to explain the answer.what will happen to the pressure of the gas as the plunger is pushed in.

Important Questions on Elements, Compounds and Mixtures

MEDIUM

Lower Secondary Stage 8

IMPORTANT

Cambridge Lower Secondary Science Stage 8 : Workbook>Chapter 4 - Elements, Compounds and Mixtures>Exercise 2>Q 7

Pierre was about to go out when he notices that his bicycle has a flat tyre.
He is looking worried because he does not know how to repair it.
Describe what happened to the amount of air in the tyre. Suggest a reason for your answer.

EASY

Lower Secondary Stage 8

IMPORTANT

Cambridge Lower Secondary Science Stage 8 : Workbook>Chapter 4 - Elements, Compounds and Mixtures>Exercise 2>Q 8

A perfume was spread at the front of the class.
The student predicted that the whole class would be able to smell the perfume.
A minute letter the student sitting near the front could smell The Perfume, but the students at the back could not. Explain this observation.

EASY

Lower Secondary Stage 8

IMPORTANT

Cambridge Lower Secondary Science Stage 8 : Workbook>Chapter 4 - Elements, Compounds and Mixtures>Exercise 2>Q 9

When concentrated hydrochloric acid reacts with concentrated Ammonia solution a white compound is formed.
A teacher set up of the following demonstration.
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Why was universal indicator included in the demonstration?

EASY

Lower Secondary Stage 8

IMPORTANT

Cambridge Lower Secondary Science Stage 8 : Workbook>Chapter 4 - Elements, Compounds and Mixtures>Exercise 2>Q 9

When concentrated hydrochloric acid reacts with concentrated Ammonia solution a white compound is formed.
A teacher set up of the following demonstration.
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Explain this observation.

HARD

Lower Secondary Stage 8

IMPORTANT

Cambridge Lower Secondary Science Stage 8 : Workbook>Chapter 4 - Elements, Compounds and Mixtures>Exercise 2>Q 10

Zak is getting ready for his sister's birthday party. He is blowing up balloons, His sister wants the balloons to be really big. This caused a problem for Zak because they keep on bursting.

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