Would extra mass in the crucible cause the "mass of oxygen" to come out too high or too low

Which of the following is true for a reliable scientific source? it cites logic. it cites opinions. it cites valid data. it cites common sense.

The amount of iron in ore can be quantitatively determined by titrating a solution of the unknown with a standard solution of dichromate, cr2o72−. the net ionic equation is 6fe2+(aq)+cr2o72−(aq)+14h+(aq)→6fe3 +(aq)+2cr3+(aq)+7h2o(aq) part a the titration of 25.0 ml of an iron(ii) solution required 18.0 ml of a 0.230 m solution of dichromate to reach the equivalence point. what is the molarity of the iron(ii) solution?

Which statement is true about market economies? government goals drive business decisions. people have the freedom to choose their jobs. several are market economies vist around the world