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

Choose the odd one out :

  1. Steel

  2. Copper

  3. Bronze

  4. Brass
Reveal answer Fill a bubble to check yourself
B Correct answer
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.

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

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 -

  1. Cu & CuO
  2. S & $SO _2$
  3. C & $CO _2$

  4. Na & NaH
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

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

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

Can we store copper sulphate in iron container and why?

  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.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

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

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

Which process use in smelting during metallurgy of coper

  1. Self reduction of copper
  2. $Cu _2S$ is converted into $Cu _2O$
  3. $FeS$ convert into $FeO$
  4. Reduction of $Fe$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Smelting of Cu result in slag formation and matle formation
FeS+Cu2O→FeP+Cu2SFeS+Cu2O→FeP+Cu2S
FCO+SiO2→FesiO3FCO+SiO2→FesiO3(slage)

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

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

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

  1. $a = 2Cu _{2}O, b = 2SO _{2}$
  2. $a = 4CuO _{2}, b = 2SO _{3}$
  3. $a = 2CuO, b = 4SO _{2}$
  4. $a = 3CuS, b = 2SO _{2}$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

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

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

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

  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. $ZnS (s) + 3O _{2} \xrightarrow{Heat} 2ZnO(s) + SO _{2}(g)$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

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

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