The hydrogen ion concentration, [H ], in the solution of phenol red solution of pH 11.20 is 6.3 X
moles/litre.
Explanation:
Data given:
basic solution of phenol red is given as it has pH of 11.2
hydrogen ion concentration = ?
the hydrogen ion concentration is calculated by using the following formula:
pH = -
[
]
Rearranging the equation:
[
] = 
Putting the values in the above equation:
[
] = 
[
] = 6.3 X
moles/litre
The hydrogen ion concentration is very small and the solution of phenol red is basic in nature. The pH of 11.2 also indicates that solution is basic and teh color of the solution is bright pink.
Answer:
Graphite is an electrical conductor, hence useful in such applications as arc lamp electrodes. It can conduct electricity due to the vast electron delocalization within the carbon layers (a phenomenon called aromaticity). These valence electrons are free to move, so are able to conduct electricity.
The total mole number of solutes will not change. So it is 25 * 10^-3 *4.525 mole. And the final volume is 25+112 = 137 mL. So the resulting concentration is mole number / volume=0.8257 M.