Advertisements
Advertisements
Question
A chemical reaction is generally accompanied by certain external indications or characteristics. These include – change of – (a) colour (b) state (c) smell (d) evolution of gas (e) formation of precipitate (f) evolution or absorption of heat. With reference to change of colour – state the change in colour seen when the following are heated – zinc carbonate.
Advertisements
Solution
Change of colour — In certain chemical reactions a change of colour is seen to be observed. Heat on substances to observe change in colour of reactants and products.
Heat on:
Zinc carbonate ZnCO3 → ZnO + CO2 [g]
Colour change:
Zinc carbonate [ZnCO3] – White – to Zinc oxide [ZnO] – Yellow (when hot)
APPEARS IN
RELATED QUESTIONS
What are the various ways in which a chemical equation can be made more informative? Give examples to illustrate your answer.
Express the following facts in the form of a balanced chemical equation:
“When a strip of copper metal is placed in a solution of silver nitrate, metallic silver is precipitated and a solution containing copper nitrate is formed”.
Name the type of chemical reaction shown by the following equation:
Fe + CuSO4 → FeSO4 +Cu
Write your observation for the following chemical reaction and name the product formed:
When sugar is heated.
Balance the following equation. Also name the product formed.
`"Zn" + "HCI" → "ZnCI" _2 + "H"_2`
The step(s) necessary for determining the percentage of water absorbed by raisins is/are:
Answer the following question:
How do acids and bases react with each other? What is the name of the process? What product is obtained from these reactions?
Give word equation for the following chemical reaction and give the names of the product formed.
NH3 + HCl→ NH4Cl
Balance the following simple equation:
Ca + H2O → Ca(OH)2 + H2
In the chemical equation the _______ are written on the left-hand side.
