Acids, Bases and Salts Flashcards
What is the pH scale?
A measure of how acidic or alkaline a solution is.
If a solution has a pH less than 7, is it acidic or alkaline?
It is acidic. The closer the pH value is to 0, the more acidic it is.
If a solution has a pH more than 7, is it acidic or alkaline?
It is an alkali or a base. The closer to 14 the number, the more alkaline it is.
What is an alkali?
A soluble base
If a solution has a pH of 7, is it acidic or alkaline?
It is neutral.
What is an example of a neutral substance?
Pure water
How can one test for pH?
Using Universal Indicator.
What colour does Universal Indicator turn when it comes into contact with an acid?
Red
What colour does Universal Indicator turn when it comes into contact with a base?
Purple
What colour does Universal Indicator turn when it comes into contact with a neutral substance?
Green
What makes a dissolved substance acidic?
H+ ions
What makes a dissolved substance alkaline?
OH- ions
What is a neutralisation reaction?
A reaction between an acid and a base.
What is the general formula for a neutralisation reactions?
Acid + Base -> salt + water
Why is water produced during a naturalisation reaction?
The acidic H+ ions react with the negative OH- ions to make water.