LSS Chapter 3: Chemical Properties Quiz

Which of the following statements about the Periodic Table is correct?

• Elements are arranged according to their chemical symbols.

• Metallic elements are found on the right-hand side.

• The zigzag line divides the elements into metals and non-metals.  

• There are more non-metallic elements than metallic elements.

Which of the following substances are elements?

• brass

• sand

• silicon

• water

Which substance will form a suspension with water?

• ethanol

• carbon dioxide

• bread crumbs

• rose syrup

Which statement does not show that seawater is a mixture?

• Seawater contains different substances

• The composition of seawater is not fixed.     

• Water in seawater is a compound.

• The components of seawater can be separated using physical methods.

Which of the following shows the correct classification of substances?

• A

• B

• C

• D

Name the three elements in vitamin C, C6H8O6.

Answer explanation

Carbon, hydrogen and oxygen

A cup of ‘Redoxon’ drink was prepared by adding one ‘Redoxon’ tablet into a cup of water and stirred. The drink was orange and clear.

(i) State if the cup of ‘Redoxon’ drink is a solution or suspension.

(ii) Explain your answer

Answer explanation

(i) Solution

(ii) Tablet cannot be seen / Solute particles cannot be seen / No insoluble substances can be seen /

Tablet dissolves in the water / no particles left undissolved /

Tablet does not settle at the bottom of the cup / Solute does not settle at the bottom of the cup / No insoluble substances settle at the bottom of the cup /

Light can pass through the drink fully;

Explain why vitamin C is a compound.

Answer explanation

Constituent elements (carbon, hydrogen and oxygen) are chemically combined in a fixed proportion by mass

Identify the solute and solvent.

Solute:

Solvent:

Answer explanation

solute: salt

solvent: water

In which beaker, A, B, C or D, does the solute have the fastest rate of dissolving?

Explain your answer.

Answer explanation

Beaker D.

The salt crystals used are small, stirring and high temperature used speed up the rate of dissolving of the solute.