Occurrence of metals - class-XII
Description: occurrence of metals | |
Number of Questions: 83 | |
Created by: Prabha Kade | |
Tags: metallurgy principles of metallurgy principles and processes of isolation of elements periodic classification of elements general principles of metallurgy production of metals materials chemistry geography in the land of kerala general principles and processes of isolation of elements |
Pyrolusite is:
Magnesium oxide is used for the lining in steel making furnace because:
During the formation of the slag by the reaction of flux and impurities which of the following is an example of acidic and basic flux?
(i) $FeO + SiO _2\rightarrow FeSiO _3$
(ii) $SiO _2+MgO\rightarrow MgO\rightarrow MgSiO _3$
A number of elements are available in earth's crust but most abundant elements are _______.
Impurities of sulphur, silicon, and phosphorus can be removed from cast iron by adding:
Sulphur molecule exists as :
In the extraction of some metals from their ores, coke can be used as:
If an ore contains impurity of $SiO _2$, identify the appropriate flux for the removal of it:
Electrolytic reduction method is used for extraction?
In metallurgy, reduction is one of the major steps. However, all ores may not require an extra reducing agent, one such metallurgical operation is the extraction of?
Reaction between which of the following results slag:
Which of the following metal occurs in native state?
The formula of the most abundant salt of sodium in nature is:
Gangue have :
The rocky material found with ores is known as............
Various processes involved on the extraction of metals from their ores and refining are known as:
Unwanted material with ore is called as ______ .
The process of extraction of metal from its ores, is known as :
The extraction of metals from their ores and then refining them for use is known as................. .
Which of the following pairs is incorrect?
Process in which the extraction of metals from ores is called:
In metallurgy, the concentration of ore is followed by the dressing of ore.
Which of the following oxides react to form slag in open hearth process?
Which metal is obtained as by-products during metallurgy of Lithium ?
Identify $x,\ y \ and \ z$ for the following metallurgical process :
$Metal\ sulphide\overset { x }{ \rightarrow } Metal\ oxide\overset { y }{ \rightarrow } Impure\ metal$
$x,\ y$ and $z$ are respectively :
Which of the following is NOT calcination?
Which of the following element is found in its native state?
In the extraction of iron slag, which of the following is formed during extraction of iron?
Which of the following statements is correct regarding the slag formation during extraction of a metal like copper or iron?
The combined state of metals are called:
Which is not a step of metallurgy ?
Sulphide ores are common for metals:
Which of following metal is extracted by electrometallurgical method-
The pair that does NOT required calcination is :
Which of the following is a basic carbonate mineral?
(i) Malachite (ii) Dolomite (iii) Azurite (iv) Magnesite
The process(es) by which lighter earthy particles are freed from the heavier particles using water is/are:
Which of the following mixture can be separated by magnetic separation?
Match the following:
(i) | Biodegradable polymer | (p) | 3-Hydroxybutanoic acid |
---|---|---|---|
(ii) | Bakelite | (q) | Phenol |
(iii) | Neoprene | (r) | 2-chlorobuta-1, 3-diene |
(iv) | Glyptal | (s) | phthalic acid |
A tin chloride $Q$ undergoes the following reaction (not balanced)
$Q + Cl^{-} \rightarrow X$
$Q + Me _{3}N \rightarrow Y$
$Q + CuCl _{2}\rightarrow Z + CuCl$
$X$ is monoanion having pyramidal geometry. Both $Y$ and $Z$ are neutral compounds. Choose the correct options(s)
Identify the ore not containing iron.
Flux is used to remove :
Which of the following metals are found in native state?
Ag, Pt, C, Si, N, O, Mg, Na, Pb
CO is toxic because it forms complex with _________ in the blood.
During smelting, an additional substance is added which combines with impurities to form a fusible mass. The additional substance is called__________.
$SnO _2$ is reduced to metallic Sn on smelting oxide with anthracite and lime. In this, the function of lime is :
Which of the following compounds are not called Thomas slag?
Composition of azurite mineral is:
Predict the mode of occurrence of the following metals:
${Ca _3(PO _4) _2}$ is :-
The most abundant metal in the earth crust is:
Which statement is correct?
Silicon is the main constituent of _______.
Removal of impurities from ore is known as:
During the process of smelting, an additional substance is added which combines with impurities to form a fusible product in metal extraction. It is known as:
Metallurgy is the process of:
RCC is:
The most abundant metal on the earth is:
___________ metals occur free in nature.
The flux used in the extraction of iron:
Specific gravity of slag is always:
Here an extraction process is given in steps. Identify the suitable ores corresponding to the process.
Pulverisation $\rightarrow$ Calcination $\rightarrow$ Smelting $\rightarrow$ Vacuum $\rightarrow$ Distillation
Gold does not occur in the combined form. It does not react with air or water. It is in the_______state.
Which one of the following is the chief ore of copper?
Which of the following is an oxide ore?
The temperature of the slag zone in the metallurgy of iron using blast furnace is:
Handpicking method is effective in:
Which metallurgy involves leaching?
Stainless steel contains:
A solution is a homogeneous mixture of two or more substances. Which of the following is a solution?
Heating a pyrite in air to remove sulphur is known as:
Which of the following is the ore of $Cu$?
The ore that can be concentrated by magnetic separation method is:
The waste, or slag, that comes out at the bottom of a blast furnace for making iron from its ore, is no thrown away. It is used for making?
Match the columns.
List I | List II |
---|---|
A. Bauxite | $1.$ Lead |
B. Haematite | $2.$ Thorium |
C. Galena | $3.$ Aluminium |
D. Monazite | $4.$ Iron |
Pig iron can be converted into steel by removing a lot of carbon contained in it, in a/ an:
The removal of unwanted impurities by mechanical methods is known as:
In manufacture of iron from Haematite, lime stone is added is act as:
Calcium silicate slag formed in extraction of iron :
Why do we need to separate different components of a mixture? Select the correct explanation from the following.
Matte contains mainly:
Which element is present in Ruby as impurity?