Unit 2: 5.1 - Salts Flashcards
What do you make when you dissolve a substance in water?
An aqueous solution.
What is an acid?
Acids are substance produce hydrogen ions (H+) when they are added to water.
What pH is an acidic solution?
Less than 7.
What is the state symbol for an aqueous solution?
(aq)
What is an alkali?
A base that dissolves in water to make an alkaline solution.
What is a base?
A base can react with an acid to neutralise it.
Give 2 features of an alkaline solution.
They produce hydroxide (OH-) ions and have pH values greater than 7.
What is the pH scale?
It has values from 0-14. Solutions that are very acidic have a very low pH of between 0 and 2. Strong alkali solutions have a high pH of between 12 and 14. Acids < 7, Alkali > 7
What is an indicator?
An indicator indicates wether a solution is acidic or alkali, often by changing colour.
What is a UI?
A universal indicator changes colour along with the pH of the solution.
What is a state symbol and what can they be?
A state symbol is used in equations to show the state of the reactants and products. They can be aqueous (aq), gas (g), liquid (l), or solid (s).
How is a salt formed?
When an acid reacts with a metal or when a acid and an alkali neutralise.
What are metal hydroxides and metal oxides?
Bases
What reaction takes place when an acid reacts with a base and what are the products?
Neutralisation. A salt in an aqueous solution and hydrogen gas are formed.
How do we get the salt from the solution?
Evaporation of the water.
What is the visible change when an acid reacts with an alkali?
There is none.
What compound is produced in every neutralisation reaction?
Water, H2O
How do we make lead iodide? What is it? How do we remove it from the solution?
We mix solutions of lead nitrate and potassium iodide. It is a precipitate which can be filtered from the solution, washed with distilled water and dried.
How can pollutants such as metal ions be removed from water?
Precipitation
How does precipitation work?
The water is treated by adding substances that react with the pollutant metal ions dissolved in the water to form insoluble salts.
How do you make a soluble salt?
React an acid with an alkali
