An alkali which on dissociation produce a high concentration of hydroxyl ions
Answers
THE STRENGTH OF ACIDS AND ALKALIS
An acid produces hydrogen ions in aqueous solution. The acidity of a solution is a measure of the concentration of the hydrogen ions in the solution.
A base produces hydroxide ions in aqueous solution. The alkalinity of a solution is a measure of the concentration of the hydroxide ions in the solution.
In 1909, Soren Sorensen proposed the pH scale for measuring acidity or alkalinity of an aqueous solution.
The pH Scale
The pH scale normally has a range of values from 0 to 14 to indicate how acidic or alkaline an aqueous solution is.
The pH value measures the concentration of hydrogen ions or hydroxide ions.
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The pH values of some common solutions used in daily life are shown below.
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The pH value of an aqueous solution can be measured by using
- Universal Indicator
- pH meter
- acid-base indicators
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Universal Indicator
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The pH range chart of Universal Indicator
Other indicator that commonly used are
- methyl orange
- phenolphthalein
- methyl red
The chart below shows the pH range for some indicators used.
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Strong and Weak Acids
A strong acid is an acid which ionises or dissociates completely in water to produce a high concentration of hydrogen ions.
A weak acid is an acid which ionises partially in water to produce a low concentration of hydrogen ions.
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Strong and Weak Alkalis
A strong alkali is an alkali which is fully ionised in water to produce a high concentration of hydroxide ions.
A weak alkali is an alkali which ionises partially in water to produce a low concentration of hydroxide ions.
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Strong alkali
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Weak alkali
The figure below shows the chemical equation for dissociation/ ionisation of strong acid, weak acid, strong base and weak base in water respectively.
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RELATED RESOURCES
Answer:
A strong alkali
Explanation: