(a) (i) Zinc blende is mainly Zinc sulphide and in industry it is converted to ZnO by flames to burn off the sulphur as SO2 which is then used to make sulphuric acid.
(ii) Reduction of ZnO to Zn:-
2ZnO + C = CO2 + 2Zn
(b) This is called sacrificial anodic protection. The zinc ( which is more reactive than iron) when in contact with the oxygen in the air is oxidised and in the process loses its electrons. These travel through the electrolyte to the iron. The electrons then reduce any iron oxide to iron: fe2+ + 2e ---> Fe.
Answer:
Cabon-12 has same average atomic weight and mass number.
Explanation:
carbon-12 has average atomic weight 12 amu and mass number of 12.
amu represents average of mass of a nucleon.
As carbon-12 has same average atomic mass and mass number therefore carbon-12 is a good standard to determine average mass of a nucleon.
Again, abundance of carbon-12 isotope is almost equal to 99%. Therefore fluctuation of average atomic weight from 12 amu is very very low.
So, carbon-12 is taken as a standard to determine mass of a nucleon.
Hence atomic mass of carbon-12 is 12 amu.
Answer : Option 4) 
Explanation :
is the only sample of matter which can be classified as a solution. As the solution can be defined as a liquid mixture which contains a minor component (the solute) that is uniformly distributed within the major component (the solvent).
In this case, the solute is
which is dissolved in water which acts as an solvent. Also, it has a subscript which is aq. which means aqueous, is often given to the solution in which the solvent is water.
Therefore,
is the correct answer.
Answer:
Keeps tides on the shore and away from the city
Explanation
The answer would be c as the cart is not in motion therefor ruling out kinetic and it is completely at rest making all of it energy potential