WorksheetsChemical Reactions and Equations
Total questions: 25
Worksheet time: 13mins
When we drop some zinc granules in copper sulphate solution, the colour of solution changes from blue to ................
White
Green
Colourless
Violet
A reddish brown coloured metal used in electric wires,
when powdered and heated strongly in an open China
dish, its colour turns black. When hydrogen gas is
passed over this black substances, it regain its original
colour. Based on this information, the metal and black
coloured substances are
copper and copper nitrate
silver and silver oxide
copper and copper oxide
aluminium and aluminium oxide
Which of the following termed as reducing agent?
Which gives oxygen
Which removes oxygen
Which removes hydrogen
All of the above
Which of the following is termed as exothermic reaction?
Reaction in which heat is evolved
Reaction in which heat is absorbed
Reaction in which there is loss of oxygen
Reaction in which there is gain of hydrogen
How rancidity can be prevented?
By adding antioxidants in food
By adding more oxygen to food
By keeping food items in open
All of the above
Which of the following is termed as rancidity?
Reduction of oxygen present in food
Oxidation of sugar present in food
Oxidation of oil present in food
All of the above
Why are articles made of iron painted to prevent rust?
Paint makes articles made of iron beautiful
Paint prevents iron articles to come in contact with moisture present in air.
Paint prevents iron articles to getting sticky
All of the above
What happens when carbon dioxide is passed in lime water?
Lime water turns milky because of formation of calcium carbonate
Lime water turns milky because of formation of water
Lime water turns red because of formation permanganate
Lime water turns red because of formation of copper sulphate
Which of the following product is formed when calcium oxide reacts with water?
Slaked lime
Carbon dioxide
Calcium oxide
Oxygen gas
Heating of ferrous sulphate gives which of the following product?
Ferric oxide
Sulphur dioxide
Sulphur trioxide
All of the above
What is the another name of quick lime?
Calcium hydroxide
Calcium oxide
Carbon dioxide
Sodium oxide
What happens when copper rod is dipped in iron sulphate solution :-
Copper displaces iron
Blue color of copper sulphate solution is obtained
No reaction takes place
Reaction is exothermic
Before burning in air, the magnesium ribbon is cleaned by rubbing with a sand paper to:
Make the ribbon surface shinier
Remove the layer of magnesium oxide from the ribbon surface
Remove the layer of magnesium carbonate from the ribbon surface
Remove the moisture from the ribbon surface
The neutralization reaction between an acid and a base is a type of:
Double displacement reaction
Displacement reaction
Addition reaction
Decomposition reaction
The displacement reaction between iron (III) oxide and a metal X is used for welding the rail tracks. Here X is:
Copper granules
Magnesium ribbon
Sodium pellets
Aluminium dust
When ferrous sulphate is heated strongly it undergoes decomposition to form ferric oxide as a main product accompanied by a change in colour from:
Blue to green.
Green to blue.
Green to brown.
Green to yellow.
It is necessary to balance a chemical equation in order to satisfy the law of:
Conservation of motion
Conservation of momentum
Conservation of energy
Conservation of mass
The respiration process during which glucose undergoes slow combustion by combining with oxygen in the cells of our body to produce energy, is a kind of:
Exothermic process
Endothermic process
Reversible process
Physical process
Silver article turns black when kept in open for a few days due to formation of
H2S
AgS
AgSO4
Ag2S
Choose the correct balanced equation of barium chloride and aluminium sulphate.
3BaCl2+Al2(SO4)3→3BaSO4+2AlCl3
2BaCl2+Al2(SO4)3→2BaSO4+2AlCl3
6BaCl2+2Al2(SO4)3→6BaSO4+4AlCl3
none of the above
A solution of X is used for white washing walls. it reacts slowly with Y in air to form a thin layer of B on walls which gives walls a shiny finish. which of the following options correctly represents X,Y and B ?
X =slaked lime , Y = nitrogen , B=calcium oxide
X =Calcium Hydroxide, Y=Oxygen, B = Calcium carbonate
X= slaked lime, Y=Carbon oxide,B= calcium chloride
X= slaked lime,Y=Carbon dioxide,B=Calcium carbonate
What are the substances on the left side called and right side of the chemical equation called respectively ?
products and reactants
groups and electrons
nothing
reactants and products
What is observed when a solution of potassium iodide is added to silver nitrate solution?
No reaction takes place
White precipitate of silver iodide is formed
Yellow precipitate of AgI is formed
AgI is soluble in water
Electrolysis of water is a decomposition reaction. The molar ratio of hydrogen and oxygen gases liberated during electrolysis of water is:
1:1
2:1
1:2
4:1
