Chemcial Changes Flashcards
What does pH mean?*
Amount of hydrogen ions present in solution.
More hydrogen ion present lower pH value, more acidic
Less hydrogen ion present higher pH value, more alkali
What is the pH of pure water
pH 7
What are methods of measuring pH levels
Litmus paper
Universal indicator
pH probe
What type of reaction is it when an acid + base react?
Neutralisation reaction
Word and symbol equation of acids reacting with bases?
acid + alkali = water + salt
H + (OH) = H20`
What is a strong acid?
Full ionise when dissolved in water
What is a weak acid?
Partially ionise when dissolved in water?
What is an example of a strong acid?
HCL
What is an example of a weak acid
Carboxylic acid eg ethanolic
What is the word equation for the disassociation of HCL
HCL =H+CL
Symbol equation of the disassociation of ethanolic acid?
CH3COOH = H+CH3COO
Compare the rate of reaction for strong and weak acids?
The rate of reaction is greater for strong acids due to increased concentration of H ions
What happens to H+ when the pH from 5 lowers to 4?
H+ in solution multiply by 10
What is the differences between strong acids and concentrated acids?
The concentrated acids are how many particles there are in a given volume, strength determines ionising ability
What is the word equation for acid and an metal oxides?
acid + metal oxide = salt + water