slop 4 Flashcards
how many atoms of each element are present in MgCl2 (small 2)
1 atom of magnesium 2 atoms of chlorine
how many atoms of each element are present in CO2
1 atom of carbon 2 atoms of oxygen
how many atoms of each element are present in FeO?
1 atom of iron 1 atom of oxygen
what is the relative formula mass of CaCO3 [40 Ca, 12 C, 16 O]
40 + 12 + (3 x 16) = 100
What may be the cause if the mass of products is less than the mass of reactants?
One of the products was a gas which escaped during the chemical reaction
what is he formula linking to concentration, mass and volume?
Concentration = mass / volume
How do we convert cm cubed to dm cubed?
divide by 1000
how to we convert dm cubed to cm cubed
multiply by 1000
state the reactivity series of metals in order, starting with the most reactive
Potassium , sodium , lithium , calcium , magnesium , carbon , zinc , iron , (hydrogen NOT METAL) , copper
do metals form positive or negative ions
positive
what forms when metals react with water
metal hydroxide and hydrogen
sodium + water —> _______ + ________
sodium + water —-> sodium hydroxide + hydrogen
what forms when metals react with dilute acid
a salt and hydrogen
magnesium + hydrochloric acid —–> ______ + _______
magnesium + hydrochloric acid —–> magnesium chloride + hydrogen
metal + oxygen —>
metal oxide
define ‘oxidation’ and ‘reduction’ in terms of oxygen
reduction is loss of oxygen, oxidation is gain
a ________ reactive metal can displace a ______ reactive metal from its compound
a MORE reactive metal can displace a LESS reactive metal from its compound
Define ‘an ore’
a rock that contains enough of a metal or a metal compound to make extracting the metal worthwhile
Which element is used to extract metals from their compounds
Carbon
What. is the main advantage of extracting a metal by heating with carbon, rather than using electrolysis
much cheaper and uses less energy
why must electrolysis be used to extract aluminium from its compounds
aluminium is more reactive than carbon
what is an alkali? give an example
a soluble substance that neutralises an acid - e.g hydroxides
what is a base? give an example
an insoluble substance that neutralises an acid - e.g oxides and carbonates
what ion do acids produce
H+
