Mix Examples of General Principles and processes of Isolation of Elements Questions in English

(C) Solder is a fusible metal alloy used to join metal workpieces together. It is primarily composed of lead $(Pb)$ and tin $(Sn)$.

(B) The correct answer is $(B)$.
Type metal is an alloy primarily composed of lead $(Pb)$,antimony $(Sb)$,and tin $(Sn)$.
The typical composition is approximately $Pb = 82\%$,$Sb = 15\%$,and $Sn = 3\%$.
Since lead constitutes the largest percentage,it consists of a higher amount of lead.

(A) In metallurgy,a flux is a substance added to remove impurities by forming a fusible slag.
$P_2O_5$ is a non-metallic oxide,which is acidic in nature.
$CaO$ is a metallic oxide,which is basic in nature.
In the given reaction,$P_2O_5$ reacts with the basic impurity $CaO$ to form a slag,$Ca_3(PO_4)_2$.
Since $P_2O_5$ is acidic and is used to remove a basic impurity,it acts as an acidic flux.

(C) Metallurgy is defined as the scientific and technological process used for the extraction of metals from their ores in a pure state.
While concentration and roasting are individual steps within this process,the term metallurgy encompasses the entire sequence of operations required to obtain the pure metal.

(A) ferrous alloy is an alloy that contains iron $(Fe)$ as its primary component.
Invar is an alloy consisting of $64\% \ Fe$ and $36\% \ Ni$.
Solder is an alloy of $Pb$ and $Sn$.
Magnalium is an alloy of $Al$ and $Mg$.
Type metal is an alloy of $Pb$,$Sn$,and $Sb$.
Therefore,Invar is the correct answer.

(B) Refractory materials are substances that can withstand very high temperatures without melting,softening,or undergoing significant chemical changes. This property makes them ideal for lining the interior of industrial furnaces.

(C) Flux is a substance added to the ore to remove gangue by forming an easily fusible material called slag.
$SiO_2$ is an acidic flux because it is an acidic oxide.
$CaCO_3$,$\text{Lime}$,and $CaO$ are basic fluxes because they are basic oxides.
Therefore,$SiO_2$ is not a basic flux.

(D) The smelting of iron in a blast furnace involves various chemical processes such as oxidation,reduction,and decomposition of ores (e.g.,$CaCO_3 \rightarrow CaO + CO_2$).
Sublimation is the transition of a substance directly from the solid to the gas phase without passing through the intermediate liquid phase.
Sublimation does not occur during the smelting of iron in a blast furnace.

(D) blast furnace is a type of metallurgical furnace used for smelting to produce industrial metals,generally iron. It is also used in the smelting of copper and lead ores. Therefore,it is employed in the metallurgy of iron,copper,and lead.

(A) The carbon content in different forms of iron is as follows:
$1$. Cast iron: $2.5-5.0\%$ carbon.
$2$. Wrought iron: $0.05-0.25\%$ carbon.
$3$. Mild steel: $0.1-0.25\%$ carbon.
$4$. Stainless steel: $0.05-1.5\%$ carbon.
Therefore,Cast iron has the highest carbon content.

(A) When the quenched steel is heated to a temperature below red hot and then allowed to cool slowly,it becomes soft. This process is known as annealing.

(B) Stainless steel is an alloy primarily composed of iron $(Fe)$,chromium $(Cr)$,and nickel $(Ni)$.
Specifically,it contains approximately $11.5 \%$ $Cr$ and $2.0 \%$ $Ni$ along with iron.
Therefore,the correct option is $(B)$.

(D) German silver is an alloy of copper,zinc,and nickel. It does not contain any silver. Its composition is approximately $Cu = 56.0\%$,$Zn = 24.0\%$,and $Ni = 20.0\%$.

(C) The correct matches are:
$(i)$ Explosive: $Pb(N_3)_2$ (Lead azide is a well-known explosive).
$(ii)$ Artificial gem: $Al_2O_3$ (Synthetic corundum is used as an artificial gem).
$(iii)$ Self reduction: $Cu$ (Copper is obtained by self-reduction of $Cu_2S$ in the Bessemer converter).
$(iv)$ Magnetic material: $Fe_3O_4$ (Magnetite is a ferromagnetic material).
Therefore,the correct matching is $(i)-E, (ii)-D, (iii)-G, (iv)-B$.

(C) Steel is an alloy of iron and carbon,where the carbon content typically ranges from $0.2 \%$ to $1.5 \%$.
Cast iron,on the other hand,contains a higher percentage of carbon,usually between $2.5 \%$ and $4.5 \%$.

(B) Steel is an alloy of iron and carbon,typically containing $0.1$ to $2.0 \%$ carbon. It is primarily manufactured from $Cast \ iron$ by removing excess carbon and impurities like $S$,$P$,$Si$,and $Mn$ through oxidation processes such as the Bessemer process or the Open-hearth process. $Wrought \ iron$ is the purest form of iron and is not the primary raw material for steel production.

(A) Spiegeleisen is a type of pig iron containing $15-30\%$ manganese and $4-5\%$ carbon.
Therefore,it is an alloy of iron $(Fe)$,carbon $(C)$,and manganese $(Mn)$.

(A) German silver is a well-known alloy consisting of copper,zinc,and nickel.
Its typical composition is $Cu$ $(60\%)$,$Zn$ $(20\%)$,and $Ni$ $(20\%)$.
Despite its name,it does not contain any silver.

(A) Case hardening: The process of hardening the surface of wrought iron by depositing a surface layer of steel on it is called case-hardening. It is done by heating wrought iron in contact with charcoal powder,which allows carbon to diffuse into the surface,increasing its hardness.

(D) The $Duplex$ process is a combination of the $Bessemer$ process and the $Open-hearth$ process.
It is specifically employed to produce high-quality steel that is almost entirely free from impurities like sulphur and phosphorus,which are difficult to remove completely in a single-stage process.

(B) Among the given options,Hard steel has the highest carbon content,which is approximately $2.3 \%$.

(A) Steel is an alloy primarily composed of iron $(Fe)$ and carbon $(C)$.
Small amounts of other elements like manganese $(Mn)$,silicon $(Si)$,phosphorus $(P)$,and sulfur $(S)$ are also present to improve its properties.
Among the given options,$Fe + C + Mn$ is the most accurate representation of the composition of steel.

(B) The process of heating steel to a high temperature and then cooling it slowly is known as $annealing$,not $quenching$.
$Quenching$ refers to the process of cooling a material rapidly,such as by dipping it in water or oil,which makes the steel hard and brittle.
Therefore,the statement in option $B$ is incorrect.

(D) . Bell metal is an alloy primarily composed of copper $(Cu)$ and tin $(Sn)$.
It typically consists of approximately $80\% \ Cu$ and $20\% \ Sn$.

(D) Manganese is added to steel to increase its hardness and wear resistance,which is essential for railroad rails.
Additionally,manganese acts as a deoxidizer and desulfurizer during the steel-making process by removing oxygen and sulfur as slag.
$Fe_2O_3 + 3Mn \rightarrow 3MnO + 2Fe$
$MnO + SiO_2 \rightarrow MnSiO_3$

(D) Pig iron is the iron obtained from blast furnaces and contains about $4 \%$ carbon and many impurities in smaller amounts (e.g.,$S, P, Si, Mn$).
Among the given options,graphite (an allotrope of carbon) is the major impurity,present in the range of $2.5 - 4.5 \%$.

(D) Stainless steel is an alloy of iron,chromium,and nickel. $A$ common composition of stainless steel is approximately $18\% \text{ Cr}$ and $8\% \text{ Ni}$ with the remainder being iron and small amounts of carbon. Among the given options,option $D$ is the most appropriate representation of the composition of stainless steel,as it contains a significant percentage of chromium.

(A, B, C, D) All the given options are correct compositions of the respective alloys.
$A$. Gun metal: $Cu (88\%), Zn (2\%), Sn (10\%), Pb (0.5\%)$.
$B$. Duralumin: $Al (95\%), Cu (4\%), Mg (0.5\%), Mn (0.5\%)$.
$C$. German silver: $Cu (50\%), Zn (30\%), Ni (20\%)$.
$D$. Solder: $Pb (50\%), Sn (50\%)$.
Since all options are factually correct,the question is likely a multiple-correct type or requires identifying the most standard representation.

(B) Solder is a fusible metal alloy used to join metal workpieces together.
It typically consists of $Sn$ $(67\%)$ and $Pb$ $(33\%)$.

(B) German silver is an alloy that consists of copper $(Cu)$,zinc $(Zn)$,and nickel $(Ni)$.
Specifically,its composition is approximately $Cu = 60\%$,$Zn = 20\%$,and $Ni = 20\%$.
Therefore,$Cu$ is one of the constituents of German silver.

(B) Gun metal is a type of bronze,which is an alloy primarily composed of copper $(Cu)$,tin $(Sn)$,and zinc $(Zn)$.
The typical composition is approximately $88\% \ Cu$,$10\% \ Sn$,and $2\% \ Zn$.
Therefore,the correct option is $(B)$.

(C) Thomas slag is a byproduct of the steel industry,primarily consisting of a mixture of calcium phosphate,$Ca_3(PO_4)_2$,and calcium silicate,$CaSiO_3$.

(B) Bronze is an alloy consisting primarily of copper,usually with tin as the main additive. It is widely used for making statues,medals,and various artifacts due to its durability and resistance to corrosion.

(D) The correct matches are as follows:
$(1)$ Stainless steel is used for making surgical instruments $(e)$.
$(2)$ Bronze is used for making coins $(c)$.
$(3)$ Nitinol (a shape-memory alloy) is used for riveting $(a)$.
$(4)$ German silver is used for making musical instruments $(d)$.
Therefore,the correct sequence is $1$ $\rightarrow e, 2$ $\rightarrow c, 3$ $\rightarrow a, 4$ $\rightarrow d$.

(A) Mild steel,also known as low-carbon steel,is a type of carbon steel with a low amount of carbon.
It typically contains between $0.05\%$ and $0.25\%$ carbon by weight.
Among the given options,the range that best describes mild steel is less than $0.2\%$ or the low-carbon range.

(A) German silver is an alloy consisting of copper $(Cu)$,zinc $(Zn)$,and nickel $(Ni)$.
Despite its name,it does not contain any silver $(Ag)$.
Therefore,the percentage of silver in German silver is $0 \%$.

(B) The reaction of chromite ore $(FeCr_2O_4)$ with sodium carbonate $(Na_2CO_3)$ in the presence of air $(O_2)$ is a key step in the extraction of chromium.
The balanced chemical equation is:
$4FeCr_2O_4 + 8Na_2CO_3 + 7O_2 \rightarrow 8Na_2CrO_4 + 2Fe_2O_3 + 8CO_2$
Thus,the products formed are sodium chromate $(Na_2CrO_4)$,ferric oxide $(Fe_2O_3)$,and carbon dioxide $(CO_2)$.

(C) Brass is a metallic alloy primarily composed of copper and zinc.
Typically,it consists of $70\% $ copper and $30\% $ zinc.

(C) The reaction of chromite ore $(FeCr_2O_4)$ with sodium carbonate $(Na_2CO_3)$ in the presence of air $(O_2)$ is the first step in the extraction of chromium.
The balanced chemical equation is:
$4FeCr_2O_4 + 8Na_2CO_3 + 7O_2 \rightarrow 8Na_2CrO_4 + 2Fe_2O_3 + 8CO_2$.
Comparing this with the given reaction,we find that $X = Na_2CrO_4$ (sodium chromate) and $Y = Fe_2O_3$ (ferric oxide).

(B) Cassiterite $(SnO_2)$ is an oxide ore of tin. The extraction process involves:
$1$. Concentration by gravity separation (washing).
$2$. Roasting to remove sulfur and arsenic impurities.
$3$. Carbon reduction of $SnO_2$ to $Sn$.
$4$. Refining by liquation.
Self-reduction is a process used for sulfide ores of metals like $Cu$,$Pb$,and $Hg$,not for $SnO_2$. Therefore,self-reduction of sulfide ore is not involved in the extraction of tin from cassiterite.

(B) The correct matches are as follows:
$I.$ Cyanide process is used for the extraction of $Au$ $(d)$.
$II.$ Froth floatation process uses pine oil as a frother $(b)$.
$III.$ Electrolytic reduction is used for the extraction of $Al$ $(c)$.
$IV.$ Zone refining is used for obtaining ultrapure $Ge$ $(a)$.
Therefore,the correct matching is $I-d, II-b, III-c, IV-a$.

(C) Flux is a substance added to the furnace to remove the gangue (impurities) present in the ore.
If the gangue is acidic (e.g.,$SiO_2$),a basic flux (e.g.,$CaO$) is added.
If the gangue is basic (e.g.,$FeO$),an acidic flux (e.g.,$SiO_2$) is added.
Therefore,flux is used to remove both acidic and basic impurities depending on the nature of the gangue. However,in the context of standard metallurgical processes,flux is primarily defined by its ability to react with gangue to form a fusible slag. Since the question asks what it removes,it removes the gangue (impurities). Given the options,it is used to remove both types of impurities,but usually,the question implies the removal of gangue which is often acidic or basic. If we must choose the most general definition,flux is used to remove gangue (impurities). Since the options are specific,the most accurate answer is that it removes impurities that are either acidic or basic. Given the standard phrasing,it is used to remove gangue (impurities). Since the options provided are limited,we select the option that covers the removal of impurities.

(B) The $Van \ Arkel$ method is a refining process used for metals like $Ti$ and $Zr$.
$Bayer's$ process is used for the purification of bauxite ore.
$Hall-Heroult$ process is used for the electrolytic reduction of alumina $(Al_2O_3)$.
$Contact$ process is used for the industrial production of sulfuric acid $(H_2SO_4)$,not for the extraction of $Al$.

(A) In a blast furnace,the reduction of iron oxides is primarily carried out by $CO$ gas,not by solid carbon $(C)$.
Reaction $A$ $(2Fe_2O_3 + 3C \rightarrow 4Fe + 3CO_2)$ does not occur because solid carbon is not the primary reducing agent for $Fe_2O_3$ in the blast furnace; instead,$CO$ is used.
Reaction $B$ $(CO_2 + C \rightarrow 2CO)$ occurs in the hotter zones.
Reaction $C$ $(CaCO_3 \rightarrow CaO + CO_2)$ is the calcination of limestone.
Reaction $D$ $(CaO + SiO_2 \rightarrow CaSiO_3)$ is the formation of slag.

(D) Flux is a substance added to the ore during smelting to remove gangue (impurities) by forming an easily fusible material called slag.
If the impurity is acidic (e.g.,$SiO_2$),a basic flux (e.g.,$CaO$) is added.
If the impurity is basic (e.g.,$FeO$),an acidic flux (e.g.,$SiO_2$) is added.
Therefore,flux is used to remove both acidic and basic impurities.

(C) Smelting is a process of reduction,not oxidation. In smelting,the roasted ore is mixed with a suitable flux and fuel and then heated to a high temperature in a blast furnace,where the metal oxide is reduced to the metal. Therefore,the statement 'Smelting - Oxidation process' is incorrectly matched.

(C) An alloy is a mixture of two or more metals or a metal and a non-metal.
Brass is an alloy primarily composed of copper $(Cu)$ and zinc $(Zn)$.
Bronze is an alloy of copper $(Cu)$ and tin $(Sn)$.
Therefore,the correct option is $C$.

(C) Cyanide process: $Ag_2S + 4NaCN \rightarrow 2Na[Ag(CN)_2] + Na_2S$. The complex formed is $[Ag(CN)_2]^{-}$.
Mond process: $Ni + 4CO \xrightarrow{330-350 \ K} Ni(CO)_4$. The complex formed is $Ni(CO)_4$.
Photographic fixing process: $AgBr + 2Na_2S_2O_3 \rightarrow Na_3[Ag(S_2O_3)_2] + NaBr$. The complex formed is $[Ag(S_2O_3)_2]^{3-}$.

(C) The Cyanide process is used for the extraction of $Au$ and $Ag$ from their ores $(A-iv)$.
Froth flotation is a method used for the concentration (dressing) of sulphide ores like $ZnS$ $(B-ii)$.
Electrolytic reduction is the standard method for the extraction of highly reactive metals like $Al$ $(C-iii)$.
Zone refining is a technique used to obtain metals in an ultrapure state,such as $Ge$ $(D-i)$.
Therefore,the correct matching is $A-iv, B-ii, C-iii, D-i$.

(B) Steel is an alloy of iron $(Fe)$ and carbon $(C)$.
Carbon is a non-metal.
Invar $(Fe-Ni)$,Bell metal $(Cu-Sn)$,and Bronze $(Cu-Sn)$ consist only of metals.