Advertisements
Advertisements
Question
Rewrite the following statements by selecting the correct options:
\[\ce{CaCO3 ->[\Delta] CaO + CO2 ^}\] is a __________ reaction.
Options
combination
displacement
double displacement
decomposition
Advertisements
Solution
Decomposition
In decomposition reactions, one compound breaks down (or decomposes) to form two or more products. When calcium carbonate is heated, it forms calcium oxide and releases carbon dioxide.
APPEARS IN
RELATED QUESTIONS
Why is the amount of gas collected in one of the test tubes in the following Activity double of the amount collected in the other? Name this gas.
- Take a plastic mug. Drill two holes at its base and fit rubber stoppers in these holes. Insert carbon electrodes in these rubber stoppers as shown in the following Fig.
- Connect these electrodes to a 6 volt battery.
- Fill the mug with water such that the electrodes are immersed. Add a few drops of dilute sulphuric acid to the water.
- Take two test tubes filled with water and invert them over the two carbon electrodes.
- Switch on the current and leave the apparatus undisturbed for some time.
- You will observe the formation of bubbles at both the electrodes. These bubbles displace water in the test tubes.
- Is the volume of the gas collected the same in both the test tubes?
• Once the test tubes are filled with the respective gases, remove them carefully. - Test these gases one by one by bringing a burning candle close to the mouth of the test tubes.
Caution: This step must be performed carefully by the teacher.
- What happens in each case?
- Which gas is present in each test tube?
Write the balanced chemical equation for the following and identify the type of reaction.
\[\ce{Zinc carbonate(s) -> Zinc oxide(s) + Carbon dioxide(g)}\]
What does one mean by exothermic reaction? Give example.
Write one equation for decomposition reactions where energy is supplied in the form of heat.
What type of reaction is represented by the digestion of food in our body?
Give one example of a decomposition reaction which is carried out with electricity.
What type of chemical reaction is used to extract metals from their naturally occurring compounds like oxides or chlorides?
What type of reaction is represented by the following equation?
\[\ce{CaCO3 -> CaCO + CO2}\]
What type of reaction is represented by the following equation?
2 FeSO4 → Fe2 O3 + SO2 + SO3
What type of chemical reaction take place when silver bromide is exposed to sunlight?
What type of chemical reaction is represented by the following equation?
X → Y + Z
What is the colour of ferrous sulphate crystals? How does this colour change after heating?
State the change in colour observed in following case mentioning the reason:
Silver chloride is exposed to sunlight.
When a green iron salt is heated strongly, its colour finally changes to brown and odour of burning sulphur is given out.
(a) Name the iron salt.
(b) Name the type of reaction that takes place during the heating of iron salt.
(c) Write a chemical equation for the reaction involved.
Classify the following reaction as combination, decomposition, displacement, precipitation and neutralization. Also balance the equation.
\[\ce{Zn_{(s)} + H2SO4 -> ZnSO4_{(s)} + H2_{(g)}}\]
Explain the following type of chemical reaction, giving two examples for it:
Decomposition reaction
MULTIPLE CHOICE QUESTIONS
Tick the most appropriate answer.
Thermal decomposition of a substance is brought about with the help of
- reactants
- water
- wind
- heat
What do you mean by redox reaction ? Explain with the help of an example.
Identify the type of following reaction :
Study the following figure and answer questions.
a) After heating Calcium carbonate, which gas is formed in a test tube?
b) When we pass this gas through limewater what change, did you observe?
c) Write down the chemical reaction showing the product formation after heating the Calcium carbonate.
(a) Design an activity to demonstrate the decomposition reaction of lead nitrate.
(b) Draw labelled diagram of the experimental set-up. List two main observations.
(c) Write balanced chemical equation for the reaction stating the physical state of the reactant and the products.
Give a balanced equation for –
An electrolytic decomposition reaction involving a neutral liquid
Give a balanced equation for –
A double decomposition neutralization reaction involving an acid and a base
Give a balanced equation for –
A white precipitate obtained during a double decomposition reaction involving a silver salt with sodium salt.
Complete the statement by filling in the blank with the correct word:
Decomposition of silver salts in the presence of sunlight is an example of _________.
Give a balanced equation for the following type of reaction:
A thermal decomposition reaction in which a compound decomposes to give two new compounds.
What is electrolysis?
When SO2 gas is passed through a saturated solution of H2S, which of the following reaction occurs?
Assertion: Decomposition of vegetable matter into compost is an endothermic reaction.
Reason: Decomposition reaction involves breakdown of a single reactant into simpler products.
Marble statues are corroded or stained rain water. Identify the main reason.
Balance the following chemical equation and identify the type of chemical reaction.
`"HgO"("s") overset("(heat)")(->) "Hg"("l") + "O"_2("g")`
Balance the following chemical equation and identify the type of chemical reaction.
`"H"_2"O"_2("l") overset("U V")(->) "H"_2"O"("l") + "O"_2("g")`
These consist of two statements – Assertion (A) and Reason (R). Answer these questions selecting the appropriate option given below:
Assertion: Silver bromide decomposition is used in black and white photography.
Reason: Light provides energy for this exothermic reaction.
What is observed when silver chloride is exposed to sunlight? Give the type of reaction involved.
Write one equation for decomposition reactions where energy is supplied in the form of electricity.
