Advertisements
Advertisements
Question
Define the following term:
Efflorescence
Advertisements
Solution
It is the phenomenon by which hydrated salts, on exposure to dry air, lose their water of crystallization and crumble to powder.
RELATED QUESTIONS
From the list of the following salts choose the salt that most appropriately fits the
description is given in the following:
[AgCl, MgCl2, NaHSO4, PbCO3, ZnCO3, KNO3, Ca(NO3)2]
On heating, this salt gives a yellow residue when hot and white when cold
The pH of a salt used to make tasty and crispy pakoras is 14. Identify the salt and write a chemical equation for its formation. List its two uses.
Which of the following salt has a blue colour and why?
CuSO4.5H2O or CuSO4
Explain why chlorine is used for sterilising drinking water supply.
What is meant by ‘a family of salts’? Explain with examples.
Write the names, formulae and colours of any two hydrated salts.
The aqueous solution of one of the following salts will turn red litmus to blue. This salt is:
The salt whose aqueous solution will have no effect on either red litmus or blue litmus is ______.
A salt is dissolved in water and the pH of this salt solution is measured with a universal indicator paper. If the pH of solution is less than 7, the salt is most likely to be ______.
How many molecules of water of crystallisation (per formula unit) are present in:
Copper sulphate crystals
State one observation for each of the following :
Lead nitric is heated strongly in a test tube.
Name the particles present in :
Strong electrolyte
Give four substances which contain water of crystallization and write their common name.
Fill in the blank
___________ is the phenomenon by which hydrated salts on exposure to dry air, lose their water of crystallization and crumble to powder.
Outline the steps required to convert hydrogen chloride to anhydrous iron (III) chloride. Write the equations for the reactions.
State what would you observe when :
Washing soda crystals are exposed to the atmosphere.
The Salt Story
From: The New Indian Express 9 March 2021
The salt pans in Marakkanam, a port town about 120 km from Chennai are the third largest producer of salt in Tamil Nadu. Separation of salt from water is a laborious process and the salt obtained is used as raw materials for manufacture of various sodium compounds.
One such compound is Sodium hydrogen carbonate, used in baking, as an antacid and in soda acid fire extinguishers.
The table shows the mass of various compounds obtained when 1litre of sea water is evaporated.
| COMPOUND | FORMULA | MASS OF SOLID PRESENT /g |
| Sodium Chloride | NaCl | 28.0 |
| Magnesium Chloride | MgCl2 | 8.0 |
| Magnesium Sulphate | MgSO4 | 6.0 |
| Calcium Sulphate | CaSO4 | 2.0 |
| Calcium Carbonate | CaCO3 | 1.0 |
| TOTAL AMOUNT OF SALT OBTAINED | 45.0 | |
How many grams of Magnesium Sulphate are present in 135g of solid left by evaporation of sea water?
One of the constituents of baking powder is sodium hydrogencarbonate. The other constituent is :
How is normal salt obtained? Give a suitable reaction.
Select the correct answer from A, B, C, D and E.
A compound which in the aqueous solution state, is neutral in nature.
