To address the given question, we need to evaluate each statement in isolation.
Statement I: During Electrolytic refining, the pure metal is made to act as an anode and its impure metallic form is used as cathode.
Analysis: In electrolytic refining, the impure metal is actually made to act as the anode, and the cathode is a strip of pure metal. The process involves the transfer of metal from the anode to the cathode, where the pure metal is deposited over time. This incorrect representation in Statement I makes it inaccurate.
Statement II: During the Hall-Héroult electrolysis process, purified Al_2 O_3 is mixed with Na_3 AlF_6 to lower the melting point of the mixture.
Analysis: This is a correct description of the Hall-Héroult process. Purified alumina (Al_2 O_3) is dissolved in molten cryolite (Na_3 AlF_6), which indeed helps in lowering the melting point to around 950-1000°C, making the electrolysis process feasible and energy-efficient. Statement II is accurate.
Conclusion: Considering the analyses above, Statement I is incorrect because it misrepresents the roles of anode and cathode in electrolytic refining. On the other hand, Statement II accurately describes a component of the Hall-Héroult process. Therefore, the correct option is: "Statement I is incorrect but Statement II is correct."
A block of mass 1 kg is pushed up a surface inclined to horizontal at an angle of \( 60^\circ \) by a force of 10 N parallel to the inclined surface. When the block is pushed up by 10 m along the inclined surface, the work done against frictional force is:

[Given: \( g = 10 \) m/s\( ^2 \), \( \mu_s = 0.1 \)]
A gas can be taken from A to B via two different processes ACB and ADB. When path ACB is used, \( 60 J \) of heat flows into the system and \( 30 J \) of work is done by the system. If path ADB is used, the work done by the system is \( 10 J \). The heat flow into the system in path ADB is:
