C4- Chemical Economics Flashcards
What is the Neutralisation of acid symbol equation?
H(+) + OH(-) =H2O
H(+) is the acid
OH(-) is the alkali
How do you calculate masses?
1) write out balanced equation
2) work out Mr
3) divide to get one (divide by itself to get 1g), multiply to get all (by number x1 by number of g on both sides)
What is the neutralisation of acid word equation?
Acid + base = salt + water
What is a base?
A substance with a PH greater than 7
What is a universal indicator used for ?
It changes colour to show what PH something is, however this is only an estimate.
That is the formula to work out percentage yield ?
Actual yield ➗Predicted yield ✖️100
Why are yield always less than 100% ?
- transferring liquids (might get left in container)
- evaporation (not just when heated)
- filtration (might be retained in filter paper)
- heating (changes the position of equilibrium)
What are the three stages in purifying water?
1) filtration
2) sedimentation
3) chlorination
What are the disadvantages of distilling sea water to her fresh water?
- expensive
- uses loads of energy
- low percentage yield
Name 5 costs of production
Labour costs Costs or raw materials Rate of reaction Energy Plant costs
What are allotropes?
Different structural forms of the same element
Name three allotropes of carbon
Diamond
Graphite
Fullerene
Why must fertilisers dissolve in water before reaching roots ?
To prevent eutrophication(chemicals in water)
What three elements do fertilisers replace?
Nitrogen
Potassium
Phosphorous
What is the word equation for producing ammonium salts?
Acid ➕ ammonia = ammonium salts
Ammonia is often used as a fertiliser to make ammonium nitrates
In flame tests what colour is….
Lithium chloride?
Sodium chloride?
Potassium chloride?
Red
Orange
Lilac
What does the group number tell us about the element ?
How many electrons are on the outer shell
What do elements in the same period have?
The same amount of shells
Why do ionic compounds have a high melting point?
Needs more energy to break bonds apart
Why do ionic compounds conduct electricity when molten or in solution
Because the ions are free to move
In group 1 metals is it more or less reactive going down
More
How many electrons do group 1 elements have in their outer shells?
1
What are superconductors ?
Materials that conduct electricity with little or no resistance
What is an isotope?
Different forms of the same element
