Answer:
A. Cu^+2(aq)cathode ---> Cu^+2(aq)anode
Explanation:
Electrolysis is the process in which current is passed through a solution thereby causing a chemical change at the anode and cathode. Copper is being purified using electrolysis by using impure copper at the anode and pure copper at the cathode. This pure and impure copper are placed in a copper(ii)sulfate electrolyte solution and dc current is made to pass through it. The resulting changes at the anode and cathode are given by the equation:
cathode: Cu²⁺ + 2e⁻ ⇒ Cu
anode: Cu ⇒ Cu²⁺ + 2e⁻
C because, its products is heavier than each of its reactants
Answer:
Self-reduction is a reaction in which no external reducing agent is required. It is called self-reducing because copper oxide itself reduced the copper sulfide to give copper and sulfur dioxide.
Grinding pepper. It is still pepper.
I hope this helps!
Answer: The sample that contains the greater number of molecules is water.
Explanation: To calculate the number of molecules, it is used the Avogadro's number ( 
particles/molecules). So, considering that the mass to water and carbon dioxide is 1g (it can be any other number), the relationship between moles and molar weight is:
To water: 
= 0.05 moles.
Therefore,
1 mol ---- molecules
0.05 moles ---- x
x = 
molecules of water.
To carbon dioxide: 
= 0.02 moles.
Therefore,
1 mol ---- molecules
0.02 moles ---- y
y = 
molecules of carbon dioxide.
