NTA Abhyas 2020
- Exam
- NTA Abhyas
- Year
- 2020
- Subject
- Chemistry
- Chapter
- General Principles and Processes of Isolation of Metals
NTA Abhyas 2020 · Chemistry · General Principles and Processes of Isolation of Metals
Which of the following statements is incorrect?
Which of the following statements is incorrect?
Options
- AIn Hall-Heroult process, the electrolyte used is a molten mixture of alumina, sodium hydroxide and cryolite.
- BLead is extracted form its chief ore by both carbon reduction and self reduction.
- CTin is extracted from its chief ore by carbon monoxide reduction.
- DSiderite and cassiterite are carbonate ores.
Correct answer
D. Siderite and cassiterite are carbonate ores.
Step-by-step solution
(i) Molten mixture of alumina and cryolite
(ii) 2\text{PbS} + 3{O}_{2} \to 2\text{Pb} + 2\text{S}{\text{O}_{2} (self-reduction)
(Self reduction)
(carbon reduction)
(iii) \text{Sn}{\text{O}_{2} + C \to Sn + CO (carbon reduction
(iv) siderite = \text{FeC}{\text{O}_{3} , cassiterite = \text{Sn}{\text{O}_{2} and argentite = \text{A}{\text{g}_{2}S.
(ii) 2\text{PbS} + 3{O}_{2} \to 2\text{Pb} + 2\text{S}{\text{O}_{2} (self-reduction)
(Self reduction)
(carbon reduction)
(iii) \text{Sn}{\text{O}_{2} + C \to Sn + CO (carbon reduction
(iv) siderite = \text{FeC}{\text{O}_{3} , cassiterite = \text{Sn}{\text{O}_{2} and argentite = \text{A}{\text{g}_{2}S.