Topic 5 - Seperate Chemistry 1 Flashcards
Where are the transition metals in the periodic table?
The Middle
What properties do transition metals typically have?
Hard, strong, shiny, malleable, conduct heat and electricity well, high melting point, high density
List some uses of transition metals
Gold is used in jewellery and electrical components
Copper is used for piping and wiring
Titanium is used to make hip replacements
What is the percentage yield formula?
percentage yield = (actual mass of product) ÷ (theoretical mass of product) × 100
Are alloys softer of harder than normal metals?
Harder than pure metals
Why use alloys instead of pure metals?
Alloys may have other beneficial properties that the metals do not have pure - eg, doesn’t rust, corrosion-proof
What is rusting an example of?
Corrosion (for iron)
What is rust called?
Iron oxide
State 4 ways of preventing corrosion
Electroplating Painting Oil Sacrificial protection Barriers
What is sacrificial protection?
Placing a more reactive metal over another, to prevent corrosion
What is electroplating?
Coating the surface of a metal with another metal using electrolysis
What does something need to corrode?
Oxygen and water
Equation for atom economy
(Total relative mass of desired products / total relative mass of all products) x 100
Is a high or low atom economy better for the environment?
High. Low atom economies use up resources very quickly and produce a lot of waste
What is a titration used to find out?
How much acid is need to completely neutralise a given quantity of alkali (and vice versa)
What colour is phenolphthalein in an acid and alkali?
Alkali - pink
Acid - colourless
What colour is methyl orange in an acid and alkali?
Alkalis - yellow
Acids - red
How do you do a titration?
Clean the burette with the acid and the beaker with the alkali. Using a pipette measure out the alkali into a beaker and add a few drops of indicator. Set up the burette over a beaker on a white tile. With the burette with the acid. Use the burette to add the acid to the alkali over time. Record the volume of the acid added to the alkali after the indicator has changed colour.
State 3 reasons why you never get 100% yield from a reaction
Incomplete reaction
Losses when transferring chemicals between containers
Unwanted reactions
