Answer:
The correct answer is "Oxidation at the anode and reduction at the cathode".
Explanation:
A rechargeable battery is recharged by the movement of electrons from an external power source into the battery. In order to achieve this, two process take place inside the rechargeable battery: oxidation at the anode and reduction at the cathode. The electrons flow within the battery from the anode to the cathode, this happens by the oxidation of the anode (loss of electrons) and the reduction at the cathode (gain of electrons).
The negative log of hydrogen or hydronium ions concentration gives the pH of the solution. The concentration of hydronium is more than the hydroxide ions.
The pH of the solution is the concentration of the hydrogen or the hydronium ion in the aqueous solution, whereas the concentration of the hydroxide ion in the solution gives the pOH.
Let the pH of the tea = 5 then,
The concentration of hydronium ion is calculated as:
The concentration of hydroxide ion is calculated as:
Calculating further:
Therefore, the concentration of the hydronium ion is much higher than that of the hydroxide ion.
Learn more about pH and pOH here:
Answer: Option (c) is the correct answer.
Explanation:
Moh's scale is used to detect the harness of a mineral. This scale displays harness of 10 minerals.
According to Moh's scale, the hardness of minerals given in the option are as follows:
Graphite is not included in Moh's scale.
Thus, we can conclude that the hardest known mineral is diamond.
sodium bromide and iodine
sodium chloride and bromine
sodium chloride and iodine