Flashcards
Topic 4
Flashcards do conjunto (20)
- 1The pH Scaleits a measure of how acidic or alkaline a solution is
the lower the pH the more acidic
the higher, the more Alkaline
a neutral substance is pH 7 - 2examples of acidic substancescar batter acid, stomach acid
vinegar
lemon juice
rain - 3examples of neutral substancespure water
- 4examples of alkaline substanceswashing up liquid
soap powder
bleach
drain cleaner - 5how to measure the pH of a solution2. an indicator is a deter that changes colour depending on if it above/below a certain pH
1. ~ a pH probe attached to a pH meter can be used to measure pH electronically
~ the probe is placed in the solution you are measuring and the pH is given on a digital display as a number - 6Acidsa substance that forms aqueous solutions with a pH of less that 7.
they form H+ ions in water - 7basesa substance with a pH greater than 7
- 8alkalia base that dissolves in water to form a solution with a pH greater than 7
they form OH- ions in water - 9the reaction between acids and basescalled neutralisation
acid + base ----> salt + water
H+ (aq) + OH- (aq) -----> H2O (I) - 10what do acids produce in water?protons
e.g = HCl ---> H+ + Cl- - 11strong and weak acids~ strong acids (sulfric, hydrochloric and nitric acids) ionise completely in water
~ weak acids (ethanoic, citric and carbon acids) do not fully ionise in water
~ the ionisation of weak acids is a REVERSIBLE reaction which sets up an equilibrium between the undissociated and dissociated acid - 12pHa measure of the concentration of Hydrogen ions
~ for every decrease of 1 on the pH scale, the concentration of H+ ions increases by a factor of 10
~ for a decrease of 2 on the pH the concentration of H+ increases by a factor of 100 - 13strong acids and concentrated acids are....DIFFERENT
did strength tells you what proportion of the acid molecules ionise in water
~ the concentration is different, it measures how much acid there is in a certain volume of water - 14metal oxide reactionacid + metal oxide ---> salt + water
- 15metal hydroxide reactionacid + metal hydroxide ---> salt + water
- 16what does the salt produced depend on?the acid and metal ion in the oxide or hydroxide
- 17metal carbonate reaction.acid + metal carbonate ---> salt + water + CO2
- 18the reactivity seriesPotassium = K
sodium = Na
Lithium = Li
Calcium = Ca
Magnesium = Mg
Carbon = C
zinc = Zn
Iron = Fe
Hydrogen = H
Copper = Cu
above Carbon - extracted by electrolysis
below, by reduction - 19metal and acid reactionacid + metal ----> salt + hydrogen
- 20metals and water reactionmetal + water ----> metal hydroxide + hydrogen
Informações
- Descrição
- GCSE Chemistry FlashCards sobre Topic 4 , criado por seren .nml em 18-03-2021.
- Criado por
- seren .nml
- Visualizações
- 1
- Avaliação