WorksheetsY9 Chem 7 chemical reactions
Total questions: 40
Worksheet time: 1hrs 1mins
The product of burning magnesium ribbon in air?
burnt magnesium
magnesium air
magnesium oxygen
magnesium oxide
magnesium dioxide
Iron filings sprinkled over the flame. What is the product of the reaction?
Ferum oxygen
Iron oxide
Ferumoxide
Iron oxygen
Which of the followings could be the metal shown in the picture? Choose two.
Magnesium
Aluminium
Sodium
Lithium
Potassium reacts violently with water and produces purple flame. Select the products of the chemical reaction.
Potassium
Potassium hydroxide
Potassium chloride
Hydrogen
Refer to the diagram and compare the reactivity of the metals. Select the correct list that start with the most reactive metal.
Na>Mg>Fe>Pb>Cu
Na>Mg>Pb>Fe>Cu
Cu>Pb>Fe>Mg>Na
Mg>Fe>Pb>Cu>Na
Magnesium reacts vigorously with hydrochloric acid and releases bubbles of gas. When a burning wooden splinter is brought near to the gas, a 'pop' sound is heard and the fire goes off. These indicates that the gas released is....
Oxygen
Carbon dioxide
Sulfur dioxide
Hydrogen
What is the advantage of jewelry made from metals like gold, platinum and silver?
They shine like diamond and is addictive.
It is easy to see them at night.
They do not corrode easily and last long.
They are very dense and hence very valuable.
Predict the products of reaction:
magnesium + iron sulfate
magnesium and iron
magnesium sulfate and iron
iron magnesium and sulfate
no reaction
Predict the products of the reaction:
zinc + copper oxide
zinc oxide and copper
copper sulfate and zinc
zinc oxide and copper oxide
no reaction
Predict the products of the reaction:
lead and iron chloride
iron and chlorine
iron lead and chlorine
lead chloride and iron
no reaction
Predict the products of the reaction:
iron + copper sulfate
copper and iron
iron sulfate and copper
copper oxide and sulfur dioxide
no reaction
The picture shows the use of a chemical reaction to fix the railway. What is the reaction?
Combustion reaction
Neutralisation reaction
Thermite reaction
Crystallization
Why carbon is commonly used to extract metals like tin and lead from their ores?
Carbon is powerful.
Carbon is very reactive.
Carbon is black.
Carbon is cheap.
Why carbon cannot be used to extract aluminium from aluminium ores?
Carbon is too cheap.
Carbon is not reactive.
Carbon is black.
Carbon is less reactive than aluminium.
How can you extract aluminium from its ores?
Burn with carbon
Use magnet
Use electric current
Use Stormbreaker
Choose the correct symbol equation for the reaction of aluminium and iron oxide.
Al (s) + Fe2O3 (s) → Fe (s) + Al2O3 (s)
2Al (s) + Fe2O3 (s) → 2Fe (s) + Al2O3 (s)
6Al (s) + 3Fe2O3 (s) → 6Fe (s) + 3Al2O3 (s)
Choose the correct symbol equation for the reaction of titanium chloride and magnesium.
TiCl4 (l) + Mg (s) → MgCl2 (s) + Ti (s)
TiCl4 (l) + 2Mg (s) → 2MgCl2 (s) + 2Ti (s)
TiCl4 (l) + 2Mg (s) → MgCl2 (s) + Ti (s)
TiCl4 (l) + 2Mg (s) → 2MgCl2 (s) + Ti (s)
Magnesium is added in excess to react with hydrochloric acid. Which process can separate the unreacted metal?
filtration
evaporation
distillation
reaction
Magnesium is added in excess to react with hydrochloric acid. Why magnesium is added in excess?
Magnesium reacts slowly. Adding more would make it reacts faster.
Magnesium is cheap. We can add in as many as we want to speed up the reaction.
This is to get more magnesium chloride.
This is to make sure all the acids are used up.
Hydrochloric acid makes chloride salts. Nitric acid makes _______ salts.
nitride
nitrogen
nitrodioxide
nitrate
Metals carbonate reacts with acids to produce salt, carbon dioxide and hydrogen.
TRUE
FALSE
Why is it better to heat the salt solution using water bath compared to direct heating?
To avoid lost of product.
The solution is toxic.
To avoid spilling of the solution.
The crystal will not form.
Which of the following test can be used to confirm that a chemical reaction releases oxygen?
Glowing splint reignites when brought close to the gas.
The fire of the burning splint goes off and produces a squeky 'pop' sound.
Lime water turns chalky.
Universal indicator turns red.
Which of the following test can be used to confirm that a chemical reaction releases carbon dioxide?
Glowing splint reignites when brought close to the gas.
The fire of the burning splint goes off and produces a squeky 'pop' sound.
Lime water turns chalky.
Universal indicator turns red.
Which of the following is the reason why pH indicator is added to the solution during neutralisation?
To know if the acid is inside the solution.
To measure the pH value of the solution.
To know when all the acids have reacted with the alkalis.
Because the book says so.
How to remove the colour of the pH indicator?
Use erasor.
Use charcoal powder.
Filter the solution with filter paper.
Do not add pH indicator.
Why cutting potatoes can help to cook faster?
That's what mum always do.
Cutting potatoes exposes more surface area, making more particles available to receive the heat energy during cooking.
The friction from the cutting produces heat energy that increases the kinetic energy of the potato particles before cooking.
Cutting potatoes reduces the total volume. We have less to cook, hence, it is faster.
Which of the following can speed up the reaction rate for magnesium and sulfuric acid? Select all that applies.
increases the volume of acid by adding water.
increases the temperature of the acid.
uses magnesium powder instead of magnesium ribbon.
uses less concentrated acid.
Which of the following could speed up the decomposition of hydrogen peroxide?
add more hydrogen peroxide.
add catalyst.
add magnesium powder.
cut hydrogen peroxide into smaller pieces.
Why increases temperature can speed up reaction rate?
There are more particles to collide with each other.
The activation energy is lowered.
The kinetic energy of particles increases which allows them to collide more.
Hot substances always cook faster.
Which reaction is faster?
Blue one.
Red one.
For the blue one, the reaction finishes at the ___th seconds.
33
55
120
0
For the blue one, the reaction slows down at ______ seconds.
0-20
20-30
30-40
40 onwards
Draw a conclusion based on the results shown in the graph.
The grey reaction is the fastest reaction.
The blue reaction is the slowest but collected the most amount of hydrogen gas.
The more concentrated the acid, the higher the reaction rate.
The faster the reaction, the smaller the volume of gas collected.
Azalee sets up the apparatus as shown in the diagram. She wants to investigate how surface area of calcium carbonate affects its reaction with hydrochloric acid. Select the variable to be changed.
size of calcium carbonate
change in mass in 1 minute
concentration of hydrochloric acid
mass of calcium carbonate
Azalee sets up the apparatus as shown in the diagram. She wants to investigate how surface area of calcium carbonate affects its reaction with hydrochloric acid. Select the variable to be measured.
size of calcium carbonate
change in mass in 1 minute
concentration of hydrochloric acid
mass of calcium carbonate
Azalee sets up the apparatus as shown in the diagram. She wants to investigate how surface area of calcium carbonate affects its reaction with hydrochloric acid. Select all the variables to be controlled.
size of calcium carbonate
change in mass in 1 minute
concentration of hydrochloric acid
mass of calcium carbonate
Why would the mass decrease after the reaction started?
calcium carbonate dissolves. It disappears.
carbon dioxide released from the reaction escapes into the surrounding.
calcium chloride is lighter than calcium carbonate.
because the reaction started.
Which of the following is true about catalyst?
Catalyst is not used up in the reaction. It can be reused.
Big chunk of catalyst can speed up the reaction faster than the powder form.
Catalyst can only be used once.
All catalyst speeds up the reaction by breaking the compounds into smaller pieces.
Platinum and gold are found in the Earth's crust as elements, not as compounds. Why is this so?
They are very reactive.
They are covered by soil particles that prevent them from reacting with other elements to form compounds.
They are not reactive.
They are shiny.
