Upgrade to remove ads
Only $35.99/year

M/J 2020 43 - Chemistry

Terms in this set (10)

State the meaning of the term weak acid.
Weak :donate or lose protons
Acid : does not fully ionise / partially ionises / forms an equilibrium mixture
Filtration and chlorination are two stages in water treatment.

State the purpose of each stage.
filtration: remove solids from water / remove insoluble substances
chlorination: sterilises / kill microbes / prevent illness
State how a colourless substance can be made visible on a chromatogram.
use a locating agent
Describe the test for a nitrate ion.
• add aqueous sodium hydroxide
• then (reduction with) aluminium (foil) (and warm)
• (ammonia gas produced which) turns damp red litmus blue
What is meant by the term electrolysis?
It is the breakdown of a molten / or aqueous ionic compound by the passage of electricity
Explain why aluminium cannot be extracted by reduction with carbon.
it is above carbon in the reactivity series / more reactive than carbon
Describe the role of cryolite in the extraction of aluminium by electrolysis
• aluminium oxide has high melting point / cryolite has lower melting point than aluminium oxide
• using cryolite reduces costs / expensive to melt aluminium
Give 4 properties of aluminium that make it suitable for use in overhead electricity cables.
• ductile / malleable
• conducts (electricity)
• low density
• protective oxide layer
State what is meant by the term strong acid :
Strong acid: An acid which dissociates completely in water and produces a large amount of hydrogen ions.
Why are weak acids poor conductors ?
It is a poor conductor because not many ions are formed
Sets with similar terms