Tag: chemistry

Questions Related to chemistry

The volatile impurities associated with zinc spelter are _______ .

chemistry general principles of metallurgy extraction of copper and zinc extraction of copper and zinc from their oxides basics of metallurgy

  1. Cd and Fe

  2. Fe and As

  3. Cd and C

  4. Cd and As

Show answer
Correct Option: D
Explanation:

The volatile impurities associated with zinc spelter are Cd and As and the non-volatile impurities are Fe and C.

Choose the odd one out :

chemistry general principles of metallurgy extraction of copper and zinc extraction of copper and zinc from their oxides basics of metallurgy

  1. Steel

  2. Copper

  3. Bronze

  4. Brass

Show answer
Correct Option: B
Explanation:
Copper is pure metal.

But steel, bronze and brass are metal alloy.

Steel is an alloy of iron and carbon, and sometimes other elements.

Brass is an alloy of copper and zinc. 

Bronze is a metal alloy consisting primarily of copper, usually with tin as the main additive, but sometimes with other elements such as phosphorus, manganese, aluminium, or silicon.

Hence, option B is correct.

A brown and bright element 'X' when heated in presence of air turns into black substance 'Y'. If hydrogen gas is passed over this heating material again 'X' is obtained 'X' and 'Y' are -

chemistry general principles of metallurgy extraction of copper and zinc extraction of copper and zinc from their oxides basics of metallurgy

  1. Cu & CuO

  2. S & $SO _2$

  3. C & $CO _2$

  4. Na & NaH

Show answer
Correct Option: A
Explanation:

$2 Cu + O _2\xrightarrow {(\Delta)} 2CuO$
(x)                            (y)
Brown & Bright         Black
$CuO + H _2 \rightarrow Cu + H _2O$

Can we store copper sulphate in iron container and why?

chemistry general principles of metallurgy extraction of copper and zinc extraction of copper and zinc from their oxides basics of metallurgy

  1. No, because Cu is more reactive than iron

  2. No, because iron is more reactive than copper, therefore reaction will take place.

  3. Yes, because copper is less reactive than iron.

  4. Yes, because copper is more reactive than iron.

Show answer
Correct Option: B
Explanation:

$Fe + CuSO _4\rightarrow FeSO _4 + Cu$
Reaction has taken place because Fe is more reactive than Cu, therefore we cannot store.

Bessemerisation is carried out for:

chemistry general principles of metallurgy extraction of copper and zinc extraction of copper and zinc from their oxides basics of metallurgy

  1. Fe, Cu

  2. Cu, Al

  3. Al, Ag

  4. Fe, Al

Show answer
Correct Option: A
Explanation:

In this process, air is blown through molten copper matte in a Bessemer converter. Bessemerisation is also used to convert pure iron to steel.

Which process use in smelting during metallurgy of coper

chemistry general principles of metallurgy extraction of copper and zinc extraction of copper and zinc from their oxides basics of metallurgy

  1. Self reduction of copper

  2. $Cu _2S$ is converted into $Cu _2O$

  3. $FeS$ convert into $FeO$

  4. Reduction of $Fe$

Show answer
Correct Option: C
Explanation:
Smelting of Cu result in slag formation and matle formation
FeS+Cu2O→FeP+Cu2SFeS+Cu2O→FeP+Cu2S
FCO+SiO2→FesiO3FCO+SiO2→FesiO3(slage)

The metal whose oxide which is amphoteric and is reduced to metal by carbon reduction is :

chemistry general principles of metallurgy extraction of copper and zinc extraction of copper and zinc from their oxides basics of metallurgy

  1. Fe

  2. Cu

  3. Al

  4. Zn

Show answer
Correct Option: D
Explanation:

Reaction:
$ZnO + C \rightarrow Zn + CO$

$2Cu _{2}S + 3O _{2}(g)\xrightarrow {heat} {a} + {b}$

In the reaction above $a$ and $b$ are:

chemistry general principles of metallurgy extraction of copper and zinc extraction of copper and zinc from their oxides basics of metallurgy

  1. $a = 2Cu _{2}O, b = 2SO _{2}$

  2. $a = 4CuO _{2}, b = 2SO _{3}$

  3. $a = 2CuO, b = 4SO _{2}$

  4. $a = 3CuS, b = 2SO _{2}$

Show answer
Correct Option: A
Explanation:

$2Cu _{2}S + 3O _{2} (g)\xrightarrow {\triangle} 2Cu _{2}O + 2SO _{2}(g)$
$2Cu _{2}O + Cu _{2}S\xrightarrow {\triangle} 6Cu(S) + SO _{2}(g)$.

$ZnO(S) + A \rightarrow Zn(s) + B$ :

chemistry general principles of metallurgy extraction of copper and zinc extraction of copper and zinc from their oxides basics of metallurgy

  1. $a = H _{2}, b = O _{2}$

  2. $a = C, b = CO$

  3. $a = S, b = SO _{2}$

  4. $a = N, b = NO$

Show answer
Correct Option: B
Explanation:

$ZnO(s) + C(s) \rightarrow Zn(s) + CO(g)$
Metal oxides are then reduced to the corresponding metals by using suitable reducing agents such as carbon.

The balance reaction involved during extraction of zinc from its ore by roasting of zinc ore :

chemistry general principles of metallurgy extraction of copper and zinc extraction of copper and zinc from their oxides basics of metallurgy

  1. $ZnS (s) + O _{2} \xrightarrow{Heat} ZnO(s) + 2SO _{2}(g)$

  2. $ZnS (s) + 3O _{2} \xrightarrow{Heat} ZnO(s) + 2SO _{2}(g)$

  3. $2ZnS (s) + 3O _{2} \xrightarrow{Heat} 2ZnO(s) + 2SO _{2}(g)$

  4. $ZnS (s) + 3O _{2} \xrightarrow{Heat} 2ZnO(s) + SO _{2}(g)$

Show answer
Correct Option: C
Explanation:

The balanced chemical reaction for extraction of zinc from its ore by roasting of zinc ore is;

$2ZnS(s)+3{ O } _{ 2 }\xrightarrow { heat } 2ZnO(s)+2S{ O } _{ 2 }(g)$