Key Concepts Flashcards
What is an independent variable?
The variable that you change to see the effect it has on another factor
What is a dependent variable?
The variable that you measure or observe
What is a control variable?
A variable that must be kept constant between each run of the experiment so that no unwanted factors affect the results
What is an extraneous variable?
A factor that might affect an experiment but cannot be measured or controlled. An example of an extraneous variable is atmospheric conditions
What is an alkali?
A soluble base, bases are the opposite of acids, forms OH- ions when dissolved in water and has a pH of 7-14
What is an acid?
A substance that produces H+ ions when dissolved in water and has a pH of 1-7
What colour is litmus in acid?
Red
What colour is litmus in alkali?
Blue
What colour is phenolphthalein in acid?
Colourless
What colour is phenolphthalein in alkali?
Pink
What colour is universal indicator in a strong acid?
Red
What colour is universal indicator in strong alkali?
Purple
What colour is methyl orange in acid?
Red
What colour is methyl orange in alkali?
Yellow
What is the word equation for the reaction between a metal and an acid?
Metal + acid -> salt + hydrogen