Extraction of Iron

Q.

What is the purest form of Iron?

Q.

What is Copper Matte?

Q. The unit cell of a metallic element of atomic mass $108gmo{l}^{-1}$and density $10.5g/c{m}^3$ is a cube with edge length of $410pm$. The structure of the crystal lattice is:

1. fcc
2. bcc
3. hcp
4. None of these

Q.

Write the chemical equation for aluminum reacts with steam.

Q. Given below are two statements.

Statement-I : Pig iron is obtained by heating cast iron with scrap iron.

Statement-II : Pig iron has a relatively lower carbon content than that of cast iron.

In the light of the above statements, choose the correct answer from the options given below.

1. Statement-I is not correct but Statement-II is correct
2. Both Statement-I and Statement-II are correct
3. Both Statement-I and Statement-II are not correct
4. Statement-I is correct but Statement-II is not correct

Q.

How is cast iron different from pig iron?

Q.

What is the chemical name of ${\mathrm{Ag}}_2{\mathrm{SO}}_3$?

Q. An element crystallises into a structure which may be described by a cubic unit cell having one atom at each corner of the cube and two atoms on one of its diagonals. If the volume of this unit cell is $24\times {10}^{-24}{\text{cm}}^3$ and density of element is $7.2{\text{g/cm}}^3$. Calculate the number of atoms present in $200\text{g}$ of the element.

1. $3.47\times {10}^{24}$
2. $9.63\times {10}^{19}$
3. $5.70\times {10}^{22}$
4. $4.44\times {10}^{24}$

Q.

This is the most widely used and also the cheapest metal.

1. Copper

2. Iron

3. Calcium

4. Gold

Q. Match List - I with List - II.
$\begin{array}{cccc}& \text{List-I}& & \text{List-II}\\ & \text{(Ores)}& & \text{(Composition)}\\ \text{(a)}& \text{Haematite}& \text{(i)}& F{e}_3{O}_4\\ \text{(b)}& \text{Magnetite}& \text{(ii)}& ZnC{O}_3\\ \text{(c)}& \text{Calamine}& \text{(iii)}& F{e}_2{O}_3\\ \text{(d)}& \text{Kaolinite}& \text{(iv)}& \left[A{l}_2\right(OH{)}_{4}S{i}_2{O}_5]\end{array}$

Q. At room temperature, sodium crystallises in body-centred cubic lattice with $a=4.24\stackrel{\circ }{A}$. Calculate the theoretical density of sodium. (Atomic mass of $Na=23.0g/mol$)

[Given, ${4.24}^3=76.22$]

1. $4.004gc{m}^{-3}$
2. $3.004gc{m}^{-3}$
3. $1.002gc{m}^{-3}$
4. $2.002gc{m}^{-3}$

Q.

The purest form of iron is prepared by oxidising impurities from cast iron in a reverberatory furnace. Which iron ore is used to line the furnance? Explain by giving reaction.

Q. Which of the following reactions represent the thermite reaction?

1. $MgC{O}_3+Si{O}_2\to MgSi{O}_3+C{O}_2$
2. $C{u}_{2}S+2C{u}_{2}O\to 6Cu+S{O}_2$
3. $F{e}_2{O}_3+3CO\to 2Fe+3C{O}_2$
4. $3M{n}_3{O}_4+8Al\to 9Mn+4A{l}_2{O}_3$

Q. The flux used in extraction of iron from haematite in the blast furnace is :

1. Silica
2. Quick lime
3. Phosphorus chloride
4. Calcium phosphate

Q.

What is meant by black ash in chemistry?

Q. $NaCl$ crystallizes in a FCC lattice. The edge length of unit cell is nearly $0.5nm$. Calculate the density of sodium chloride
Take $N_A=6\times {10}^{23}$
and
$\text{Molecular mass of}NaCl=58.5gmo{l}^{-1}$

1. $0.33gc{m}^{-3}$
   
2. $3.12gc{m}^{-3}$
3. $1.55gc{m}^{-3}$
4. $6.24gc{m}^{-3}$

Q. How many units cells are there in $1.00\text{g}$ cube shaped ideal crystal of $AB$ (MW = 60 u) which has a $NaCl$ type lattice.
(Take, $N_A=6\times {10}^{23}$)

1. $60.2\times {10}^{23}$
2. $1.00\times {20}^{22}$
3. $2.50\times {10}^{21}$
4. $6.02\times {10}^{24}$

Q. Which among the following is not an ore of zinc?

Q.

In the metallurgy of Iron, limestone is added to the ore. Why?

Q.

Among the reactions (a) – (d), the reaction(s) that does/do not occur in the blast furnace during the extraction of iron is/are:

(a) $\mathrm{CaO}+{\mathrm{SiO}}_2\to {\mathrm{CaSiO}}_3$

(b) $3{\mathrm{Fe}}_2{\mathrm{O}}_3+\mathrm{CO}\to 2{\mathrm{Fe}}_3{\mathrm{O}}_4+{\mathrm{CO}}_2$

(c) $\mathrm{FeO}+{\mathrm{SiO}}_2\to {\mathrm{FeSiO}}_3$

(d) $\mathrm{FeO}\to \mathrm{Fe}+(1/2){\mathrm{O}}_2$

1. (a)

2. (d)

3. (c) and (d)

4. (a) and (d)

Q. The slag formed in the extraction of iron and copper respectively are

1. $CaSi{O}_3\text{and}Si{O}_3$
2. $FeSi{O}_3\text{and}CaSi{O}_3$
3. $MgSi{O}_3\text{and}FeSi{O}_3$
4. $CaSi{O}_3\text{and}FeSi{O}_3$

Q.

The Goldschmidt thermite process is also known as Aluminothermic process – True or False?

1. True

2. False

Q. Carbon cannot be used to produce magnesium by chemical reduction of MgO because:

1. Carbon is not a powerful reducing agent
2. Magnesium reacts with carbon to form carbides
3. Magnesium is less electropositive than carbon
4. Carbon does not react with magnesium

Q.

$\mathrm{ZnO}$ when heated with Carbon at $1000°\mathrm{C}$ is reduced to $\mathrm{Zn}$ metal and $\mathrm{CO}\left(\mathrm{g}\right)$ is evolved. Write a balanced reaction and underline the reducing agent.

Q.

The following reactions take place in the blast furnace in the preparation of impure iron. Identify the reaction pertaining to the formation of slag.

1. $2\mathrm{C}\left(\mathrm{s}\right)+{\mathrm{O}}_2\to 2{\mathrm{CO}}_2\left(\mathrm{g}\right)$

2. ${\mathrm{CaCO}}_3\left(\mathrm{s}\right)\to \mathrm{CaO}\left(\mathrm{s}\right)+{\mathrm{CO}}_2\left(\mathrm{g}\right)$

3. $\mathrm{CaO}\left(\mathrm{s}\right)+{\mathrm{SiO}}_2\left(\mathrm{s}\right)\to {\mathrm{CaSiO}}_3\left(\mathrm{s}\right)$

Q. Which of the following statements is correct wrt the following graph?

1. Below $1623K,Mg$ reduces $A{l}_2{O}_3$ to Al
2. Above $1623K,Al$ reduces $MgO$ to Mg
3. Both (a) and (b) are correct
4. 
   Both (a) and (b) are wrong

Q.

Write down the reactions taking place in blast furnace related to the metallurgy of iron in the temperature range 500-800 K.

Q. How pig iron is converted into cast iron ?

Q.

Why is sulphide ore of copper heated in a furnance after mixing with silica?

Q.

The statement given below is incorrect. Write the correct statement.

Copper carbonate on strong heating leaves behind a residue which is green in colour.