Reactions With Acid Flashcards
What is the pH scale?
The pH scale is a measure of how acidic or alkaline a solution is.
What is an acid?
A substance with a pH of > 7 and that forms H+ ions in water.
What is an alkali?
A substance with a pH of < 7 and that forms OH- ions in solution.
What is the pH of a neutral substance?
7
What is a Neutralisation Reaction?
The reaction between acids + bases/alkali to produce neutral products (eg. salt and water).
How do you produce a pure, dry sample of salt?
- Neutralisation reaction with excess acid
- Filter out the salt
- Heat to evaporate water
- Leave crystals to dry
What does a Universal Indicator do?
A universal indictor measures the approximate pH.
What colour would a Universal Indicator change to for…
- Acids
- Neutral
- Alkali
- Red, orange, yellow
- Green
- Blue/purple
What are bases?
A substance that reacts with acids in neutralisation reactions?
How can you tell if an acid is strong?
Strong acids ionise completely in water. (All ions dissociate to release H+ ions)
What are bases which are soluble in water?
Alkalis
How can you determine that pH of a solution?
- A pH probe
- A Universal Indicator.
What is the equation for a neutralisation reaction?
(H+) + (OH-) -> (H2O)
ignore brackets.
How does Hydrochloric acid react with metal?
Produces salts ending in ‘-chloride’
How does Sulfuric Acid react with metal?
Produces salts ending in ‘-sulfate’
