<span>Carboxylic acid.
This is because there is no reducing termini. and if one end is a methyl, that is just hydrocarbons, and the rest must also be hydrocarbons. We can assume that there are no other constituents that are making functional groups and given with what we have this is a carboxylic acid.</span>
The Answer is D. a polymer is a substance that has a molecular structure consisting of a large number of similar units bonded together
I think you mean:
".. reacts with oxygen gas to produce lead (II) oxide and 'sulfur' dioxide..."
The balanced chemical reaction would be
2PbS + 3O2 --> 2PbO + 2SO2
The stiochiometric ratio is this: 3 moles of O2 produces 2 moles of lead (II) oxide. So,
0.500 moles (2/3) = 0.333 moles
Therefore, 0.333 moles of PbO is produced when 0.500 moles of O2 reacts with PbS.
Suspension. The particles are big enough for the eye to see, and will separate if left sitting.
Centi- (symbol c) is a unit prefix in the metric system denoting a factor of one hundredth.