Magnetic Separation

Q. How many metallic ores are concentrated by the magnetic separation method from the given ores?
Cassiterite, pyrolusite, rutile, magnetite, galena, cinnabar.

Q. Froth floatation process is used for the concentration of sulphide ores. This process is an illustration of the practical application of:

1. adsorption
2. absorption
3. sedimentation
4. coagulation

Q. An ore of tin $Sn{O}_2$ containing $FeCr{O}_4$ is concentrated by:

1. magnetic separation
2. froth floatation
3. gravity separation
4. None of the above

Q. Concentration of bauxite is done by different methods as there are different types of bauxite. Consider the process for concentration of bauxite.
Process 1 : Employed for red bauxite to remove main impurity iron oxide.
Process 2 : Employed for white bauxite to remove main impurity silica.

1. 1 : Baeyer method, 2 : Serpeck's method
2. 1 : Hoopes method, 2 : Serpeck's method
3. 1 : Hall-Heroult process, 2 : Hoopes method
4. 1 : Baeyer method, 2 : Hoopes method

Q. Magnetic separation is suitable for which one of the following ores?

1. Galena
2. Cinnabar
3. Cassiterite
4. Sphalherite

Q. The process(es) by which lighter earthy particles are freed from the heavier particles using water is/are:

1. Gravity separation
2. Magnetic separation
3. Hydraulic washing
4. Leaching

Q. The catalyst used in making $H_{2}S{O}_4$ in contact process is :

1. $V_2{O}_5$
2. $Cr{O}_3$
3. $F{e}_2{O}_3$
4. $C{r}_2{O}_3$

Q. An ore containing the impurity of $FeC{r}_2{O}_4$ is concentrated by __________.

1. magnetic-separation
2. gravity separation
3. froth-floatation method
4. electrostatic method

Q.

Gravity separation is generally applicable for heavier ores such as Haematite and Cassiterite.

1. True

2. False

Q. In froth floatation process, gangue articles are wetted by pine oil.

1. True
2. False

Q. When do we use magnetic separation method for concentration of an ore? Explain with an example?

Q. Differentiate between minerals and ores.

Q. Gravity separation process is used for the concentration of _____________.

1. calamine
2. haematite
3. bauxite
4. chalcopyrites

Q. Which of the following statements is true about magnetic separation?

1. It is used when only ores are magnetic in nature.
2. It is used when only impurities are magnetic in nature
3. It is used when both ores and impurities are magnetic in nature.
4. It is used when either ore or impurities are magnetic in nature.

Q. An ore of tin containing $FeCr{O}_4$ is concentrated by:

1. magnetic separation
2. froth floatation
3. electrostatic
4. gravity separation

Q. A mixture of ____________ can be separated by magnetic attraction.

1. copper and steel
2. copper and tin
3. sand and tn
4. iron and steel

Q. Cassiterite ore $\left(Sn{O}_2\right)$ is purified by:

1. magnetic separator
2. roasting
3. leaching
4. calcination

Q. Which of the following process is not a physical process of separation?

1. Magnetic separation
2. Levigation
3. Leaching
4. Froth fioatation

Q. Sulphide ore is concentrated by the method:
1. Froth flotation process
2. Magnetic separation
3. Gravity method
4. Calcination method

Q.

Gravity separation is generally applicable for heavier ores such as Haematite and Cassiterite.

1. True

2. False

Q. In aluminium extraction by the Bayer process, alumina is extracted from bauxite by sodium hydroxide at high temperatures and pressures.
${Al}_2{O}_3\left(s\right)+2O{H}^{-}\left(aq\right)\to 2Al{O}_2^{-}\left(aq\right)+H_{2}O\left(l\right)$
Solid impurities such as ${Fe}_2{O}_3$ and $Si{O}_2$ are removed and then $Al{\left(OH\right)}_4^{-}$ is reprecipitated
$2Al{\left(OH\right)}_4^{-}⟶{Al}_2{O}_3\cdot 3H_{2}O\left(s\right)+2O{H}_{\left(aq\right)}^{-}$.
In the industrial world __________.

1. carbon dioxide is added to precipitate the alumina
2. temperature and pressure are dropped and the supersaturated solution seeded
3. both (A) and (B) are practised
4. the water is evaporated

Q. Which of the following statements is true about magnetic separation?

1. It is used when only ores are magnetic in nature.
2. It is used when only impurities are magnetic in nature
3. It is used when both ores and impurities are magnetic in nature.
4. It is used when either ore or impurities are magnetic in nature.

Q.

Tin stone or Cassiterite can be separated from gangue by

1. calcination

2. magnetic separation

3. gravity separation

4. roasting

Q. Select the correct statement(s):

1. Gravity separation method is used in concentration of oxide ore and carbonate ore
2. Magnetic separation method is used for separation of non - magnetic rutile and magnetic impurity of chlorapatite
3. $F{e}_3{O}_4$ is magnetic and impurities non - magnetic
4. $Mn{O}_2$ is non - magnetic and impurities magnetic

Q. Zinc acts as a reducing agent in the extraction of silver. Comment.

Q. In the magnetic seperation method which possess magnetic properties the ore or the gangue particles.

Q. Which is not the correct statement?

1. Cassiterite, chromite and pitchblende are concentrated by hydraulic washing (Tabling).
2. Pure $A{l}_2{O}_3$ is obtained from the bauxite ore by leaching in the Baeyers process.
3. Roasting can convert sulphide into oxide or sulphate and part of sulphide may also act as a reducing agent.
4. Sulphide ore is concentrated by calcination method

Q. As the size of gold particle increases, the colour of solution varies as :

1. Purple$\to$ Blue$\to$ Golden$\to$ Red
2. Golden$\to$ Red$\to$ Purple$\to$ Blue
3. Red$\to$ Purple$\to$ Blue$\to$ Golden
4. Blue$\to$ Purple$\to$ Golden$\to$ Red

Q. Explain hybridisation and geometry as well as magnetic nature of [Mn(CN)6]^3- and [Mn(Cl)6]^3-.

Q. Nature of some ores are given. Pick ore concentration from the bracket.
(Magnetic Separation , Froth Floatation , Levigation , Leaching)
Ore is magnetic but impurities are nonmagnetic.