Awesome Acids Flashcards
What is pH?
pH indicates if a substance is acid, alkali or neutral.
What is the pH Scale?
The pH scale is a measure of how acid alkali or neutral a substance is. The pH scale has a range of 0 to 14. pH 7 is classed a neutral.
What is an acid?
It is the chemical opposite of an alkali. Acids have a pH ranging from 0-6. pH0 is classed as a strong acid. pH6 is classed as a weak acid.
What is an alkali?
It is the chemical opposite of an acid. Alkali’s have a pH ranging from 8-14. pH8 is classed as a strong alkali. pH14 is classed as a weak alkali.
What is a neutral solution?
A neutral solution is neither acid or alkali. It is perfectly in the middle of the pH scale. It has a pH of 7.
Are all acids dangerous?
No… Many acids are weak. We consume many acidic substances and no harm comes to us, e.g. vinegar, coke, and citrus fruits or juices.
What is more dangerous a strong acid or a strong alkali.
Both are extremely dangerous, strong acids and alkalis are very corrosive. They would be very harmful if you came into contact with them.
Name some common household acids.
Acetic acid is also known as vinegar
Citric acid is in citrus fruits and fruit juices
Lactic acid is found in mild and dairy products
Sulphuric acid is found in batteries and drain cleaners
Ascorbic acid is vitamin C
Name a some common household alkalis.
Common household alkalis include indigestion tablets (antacids), bleach, toothpaste, baking powder, cream cleaner, oven cleaner, metal polish and alkaline batteries. They can have moderate to severe levels of toxicity.
Name some neutral solutions
Distilled water, table salt, sugar and cooking oil.
Describe the pH Scale in terms of colour (what colour are acids, alkali’s and neutral?
Acids run from a deep red (strong acid) through to orange then yellow (weak acid). Neutral is green. Alkalis run from greeny/blue (weak alkalis) through to darker blues then purple (strong alkalis).
What is an chemical indicator?
It is a substance that can change colour with different pH’s
Name the 2 most common indicators we use in the lab.
Also name one indicator solution that we can make.
pH paper and universal indicator. However the dye from different brightly coloured plant materials can be extracted to produce an indicator solution e.g. red cabbage.
Describe how you would use pH paper to test a substance.
To clarify whether a solution is acidic, neutral or alkaline, pH paper is used. When the pH paper is dipped into the solution the indicator’s colour changes and by matching the indicator colour to a colour chart you can determine the pH of the substance.
What is a neutralisation reaction?
A neutralisation reaction is one where an acid, or an alkali, is cancelled out (it becomes neutral ph7).
