acids & alkalis Flashcards
When acids are added to water they form…
When alkalis are added to water they form…
positively charged hydrogen ions (H+)
negative hydroxide ions (OH-)
Define a base vs alkali.
Base - any substance that reacts with an acid to form a salt & water only.
Alkali - bases that are soluble in water.
Describe the pH scale.
- acids have pH values below 7
- alkalis have pH values above 7
- solution of pH7 is neutral
What are the 3 indicators, and what are their colours in acids & alkalis?
- Litmus - red - blue
- Phenolphthalein - colourless - pink
- Methyl orange - red - yellow
The pH scale is … meaning each change of 1 represents a change in concentration by a factor of…
logarithmic
10
Describe strong vs weak acids.
Strong acids dissociate completely producing solutions with high concentration of H+ ions & low pH.
Weak acids only partially ioniser producing solutions of pH between 4-6.
A dilute solution contains a… amount of…
A concentrated solution contains a… amount of…
small, solute
large, solute
