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41 Cards in this Set
- Front
- Back
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Is a nucleus positively or negatively charged |
Positively |
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Are electrons positively and negatively charged |
Negatively |
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Atoms can form bonds to make what? |
Molecules or compounds |
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What charge does an atom become when it looses electrons |
Positive |
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What charge does and atom become if it gains electrons |
Negative |
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What are charged atoms known as |
Ions |
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How does an ionic bond occur |
When a positive ion meets a negative ion and are attracted |
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What do atoms in a covalent bond share |
A pair of electrons |
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What does the molecular formula show |
The number and type of atoms in a molecule |
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What does the displayed formula show |
The atoms and the covalent bonds in a molecule |
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Why are additives added to lots of out foods |
To improve their flavour, colour or to make them last longer |
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Why are food colours used |
To make food look more appetising |
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What do flavour enhancers do |
Bring out the taste and smell of food |
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Why are antioxidants used |
To help preserve food |
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Why are emulsifiers used |
To help oil and water blend together |
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What happens when protein molecules are heated |
They change shape |
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How do the protein molecules change shape |
The energy from cooking breaks some of the chemical bonds in the protein |
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What is each potato cell surrounded by? What is it made of |
A rigid cell wall. It's made of cellulose |
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What does cooking potatoes do to the cell wall |
It ruptures them |
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What does cooking the potato do to the starch grains inside the cell |
They swell up and spread out |
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How does the change in the cell wall and starch grains effect the potato |
It makes the potato softer, more flexible and it makes it easier to digest |
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What does baking powder undergo when heated |
Thermal decomposition |
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What is thermal decomposition |
When a substance breaks down into simpler substances when heated |
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What does the carbon dioxide produced in the thermal decomposition of baking powder do |
Makes the cakes rise |
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What is the word equation for thermal decomposition in baking powder |
Sodium hydrogencarbonate ==> sodium carbonate + carbon dioxide + water |
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What is the symbol equation for thermal decomposition in baking powder |
2NaHCO3 ==> Na2CO3 + CO2 + H2O |
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What are esters often used as |
Perfumes |
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What does paint usually contain |
Solvent Binding medium Pigment |
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Why is pigment in paint used |
It gives the paint its colour |
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What is binding medium and what does it do |
It is a liquid and it carries the pigment bits and holds them together |
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What happens when the binding medium goes solid |
It sticks the pigments to the surface that is painted |
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Why is the solvent used |
To thin the paint which makes it easier to spread |
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What does a colloid consist of |
Really tiny particles of one kind of stuffed dispersed in another kind of stuff. They're mixed in but not dissolved |
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When to water based emulsions dry |
When the solvent evaporates, leaving behind the binder and pigment as a thin solid film |
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What are the two stages of how oil paints dry |
First the solvent evaporates and then the oil is oxidised by oxygen in the air before it turns solid |
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How are polymers formed |
When lots of small molecules called monomers join together |
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What is the reaction called when polymers are formed |
Polymerisation |
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What do the monomers that make up addition polymers have |
A double covalent bond |
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What are unsaturated compounds |
Molecules with at least one double covalent bond between carbon atoms |
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How are polymer chains formed |
When lots of unsaturated monomer molecules open up their double bonds and join together |
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What kind of polymer is nylon |
Synthetic |
