The chemical equation below shows the combustion of methane (ch4).

ch4+2o2--co2+2h2o

the molar mass of oxygen gas (o2) is 32.00 g/mol. the molar mass of carbon dioxide (co2) is 44.01 g/mol. what mass of co2, in grams, will firm when 8.94 g o2 completely react?
a)3.25
b)6.15
c)13.0
d)53.0

The atoms of a solid aluminum can are close together, vibrating in a rigid structure. if the can is warmed up on a hot plate, what happens to the atoms?

Is this correct if not can u correct me

Tooth enamel consists mainly of the mineral calcium hydroxyapatite, ca_10(po_4)_6(oh)_2. trace elements in teeth of archaeological specimens provide anthropologist with clues about diet and diseases of ancient people. students at hamline university measured strontium in enamel from extracted wisdom teeth by atomic absorption spectroscopy. solutions with a constant total volume of 10.0 ml contained 0.726 mg of dissolved tooth enamel plus variable concentrations of added sr. added sr find the concentration of sr in the 10 ml sample solution in parts per billion = ng/ml. find the concentration of sr in tooth enamel in parts per million = mu g/g.