Sci Chem Revision 2019 Paper

Name the substance that is used to reduce iron oxide in blast furnace.

• calcium carbonate

• carbon monoxide

• carbon

• carbon dioxide

Name the substance used to raise the pH of soil in a farmer's field.

• calcium dioxide

• calcium oxide

• calcium carbonate

• calcium chloride

The relative charge of proton is

Name the physical property that allows fractions to be separated in a fractional distillation.

Boiling point of nitrogen is -196^oC and oxygen is -183^oC. Which gas will be collected first in this process?

• nitrogen gas

• oxygen gas

Acids react with ............... ....................... to produce salt, water and carbon dioxide.

To prepare sodium sulfate (soluble in water), sodium hydroxide should be titrated with ............. ...............

High heat can cause decomposition of compounds.

• True

• False

What is the first step to solve this question?

• Calculate the number of moles of Ni immediately because I have values to substitute into the formula.

• Calculate the number of moles of Ni(CO)₄ because the mass of this compound is given.

• State the stoichiometry (ratio) of the elements and compounds in the reaction.

Acids react with alkali to produce ………. and ……….. (use a comma to separate your answer when you type).