Advertisements
Advertisements
Question
Explain concept with example/explain with the help of a balanced equation.
Roasting
Solution
- The process of heating of sulphide ores strongly in excess of air to convert it into respective oxide is called roasting.
- For example, zinc sulphide is heated strongly in excess of air to convert it to zinc oxide.
\[\ce{\underset{\text{Zinc sulphide}}{2ZnS_{(s)}} + 3O_{2(g)} -> \underset{\text{Zinc oxide}}{2ZnO_{(s)}} + \underset{\text{Sulphur dioxide}}{2SO_2↑}}\]
APPEARS IN
RELATED QUESTIONS
Which of the following pairs will give displacement reactions?
In the electrolytic refining of a metal M, what would you take as the anode, the cathode and the electrolyte?
A zinc ore gave CO2 on treatment with a dilute acid. Identify the ore and write its chemical formula.
Name one metal which is extracted by reduction with aluminium.
Fill in the following blank with suitable word:
The non-metal present in steel is ............
Give the name and chemical formula of one ore of copper.
Which gas is produced during the extraction of aluminium? At which electrode is this gas produced?
The metal which can be extracted from pyrolusite ore is:
(a) mercury
(b) manganese
(c) aluminium
(d) magnesium
Which metal can be extracted from the following ore?
Haematite
State why aluminium is extracted from its oxide by electrolysis while copper, lead, iron by reducing agents and mercury and silver by thermal decomposition.
Give reasons, why aluminum is used in:
In making ships
How an ore is concentrated by froth floatation process?
Name : The metal which is liquid at room temperature.
Iron is _______.
_______ is the least reactive metal.
Find the odd one out and give its explanation.
Explain the concept of Calcination.
Which of the statements about the reaction, \[\ce{ZnO + CO -> Zn + CO2}\] is correct?
Two ores A and B were taken. On heating ore A gives CO2 whereas, ore B gives SO2. What steps will you take to convert them into metals?
On the basis of reactivity metals are grouped into three categories:
- Metals of low reactivity
- Metals of medium reactivity
- Metals of high reactivity
Therefore metals are extracted in pure form from their ores on the basis of their chemical properties.
Metals of high reactivity are extracted from their ores by electrolysis of the molten ore.
Metals of low reactivity are extracted from their sulphide ores, which are converted into their oxides. The oxides of these metals are reduced to metals by simple heating.
(a) Name the process of reduction used for a metal that gives vigorous reaction with air and water both.
(b) Carbon cannot be used as a reducing agent to obtain aluminium from its oxide? Why?
(c) Describe briefly the method to obtain mercury from cinnabar. Write the chemical equation for the reactions involved in the process.
OR
(c) Differentiate between roasting and calcination giving chemical equation for each.