8. Acids & Bases Flashcards
What is the number range of the pH scale?
1-14
What does the pH scale measure?
The acidity or alkalinity of a substance
What is the pH range for acids?
Less than 7
What is the pH range for alkalis?
Greater than 7
Name 3 indicators used in the lab
pH paper universal indicator red cabbage indicator
What is the pH value for neutral solutions?
7
What are produced when a metal reacts with an acid?
A salt and hydrogen
What is the test for hydrogen?
It burns with a pop
What is meant by neutralisation (S2)?
The pH value moves towards and reaches 7
How do you test for pH value?
- Add some suitable indicator to substance 2. Match colour to appropriate colour chart 3. Read off pH value matching that colour
Do strong acids have a higher or lower pH than weak acids?
Lower
Do strong alkalis have a higher or lower pH than weak alkalis?
Higher
What are the 3 acids used in the lab?
- Hydrochloric acid
- Sulphuric acid
- Nitric acid
What is the formula for hydrochloric acid?
H+ Cl- (aq)
What is the formula for sulphuric acid?
(H+)2 SO42- (aq)