AQA Core Chemistry - C1.1 - C1.6 Flashcards
What is a compound?
Two or more elements chemically combined
What is the charge on a proton?
Positive
What does the atomic number tell us?
The number of protons and electrons which the atom has
What does the mass number tell us?
The number of protons and neutrons the atom has
How do you work out the number of neutrons?
Mass number - atomic number
How many electrons can fit into the first 3 shells or orbitals?
1st = 2, 2nd = 8, 3rd = 8
What does the group number on the periodic table tell us?
The number of electrons in the outside shell - each element in the group will have the same number of electrons in their outer shell
What does the period (row) number tell us?
The number of shells the element has
What are elements in Group 0 called and why?
Noble gases as they are unreactive
What is the formula of calcium hydroxide?
Ca(OH)2
cement + sand + mortar = ???
concrete
Limestone + clay = ???
cement
Limestone + sand + sodium carbonate = ???, Under what condition does this have to be under (extra mark)
glass, strong heat
Chemical name for Limestone…
calcium carbonate
Breaking down a chemical by heating is called…
thermal decomposition
Chemical Equation for thermal decomposition of limestone…
calcium carbonate = calcium oxide + carbon dioxide
Lime water is a test for…
carbon dioxide (turns limewater milky)
What is a metal ore…
A metal in its natural state
What is native state…
metals are so unreactive they are found as their elements e.g. Gold
What is the best way to extract a metal from its ore…
using the reactivity series (i.e. displacement/ reduction)
Metal oxide + carbon = two products. What are they?
metal + carbon dioxide
Removal of oxygen is called…
reduction reaction
Metal containing other elements is called…
alloy
What is carbon steel used for?
cars, knives, containers, structural steel
What are the properties of high carbon steel?
very strong, but brittle
Main advantage of stainless steel?
Does not rust
A property of copper is…
Very soft (Also great conductor of heat/electricity)
Name 3 (of a possible 4) properties of transition metals…
good conductors of heat and energy, hard tough and strong, malleable, high melting points
Name two cheaper, more environmental friendly ways to extract copper
bacteria (bioleaching) and plants (phytomining)
Which two elements resist corrosion and are therefore very useful?
aluminium and titanium
What are the disadvantages of the two transition elements that resist corrosion (extra mark - state them)
take a lot of energy to extract from their ores and therefore are expensive - Al and Ti
Disadvantage of electrolysis…
very expensive due to high temperatures and electricity needed. Lots of energy
Why is aluminium recycling important?
takes less energy to produce the same amount from recycled metal than from its ore by extraction