Chapter 7 - Food Chemistry Flashcards
what is a mixture
a mixture is when 2 substances are not chemically combined together
what are the seperating techniques
dissloving, filtration, evaporation, distillation & chromatography
what is dissolving
dissolving is seperating solids by adding water into the mixture
what is filtration
filtration is used to seperate an insoluble soild from a liquid
what is the soild collected in the filter paper
residue
what is the liquid collected in the beaker ( filtration )
filtrate
what is evaporation
evaporation is used to seperate a dissolved solid from a liquid ( eg. salt water )
what is distillation
it is used to seperate a liquid from a solution
what is chromatography
it is used to seperate a mixture into it’s coloured components
if the dye’s position is further up
it is more soluble
if the dye’s position is at the lower point of the paper
it is less soluble
what is chemical reaction
it happens around us. it must have a new product once the chemical reaction has happened
examples of chemical reactions
rusting of nails, cooking of food, burning paper and food decay
what is an acid
an acid gives off hydrogen and ion in an aqueas state.
we can identify an acid by…
its sour taste , the color change in the universal indicator , the blur litmus paper turns red
what is the pH value of lime water
4 ( acidic )
what is the pH value of vinegar
3 ( acidic )
what is the pH value of car battery
0 ( very acidic )
what is the word equation for the reaction with acid and metal
acid + metal = salt + hydrogen gas
what is the word equation for the reaction with acid and carbonate
acid + carbonate = salt + carbon dioxide + water
if we do not have our regular meals, we will get gastric. what do we take in order for us to get better
antacids
what is the word equation for neutralisation
acid + base = salt + water
what is neutralisation
neutralisation is when an acid reacts with a base ( like antacids )
examples of neutralisation
- hair conditioner
- fabric softener
- tooth decay
