Both "<span>Do high pressure systems prefer forming in Ecuador compared to in Springdale?" and </span>"<span>Are average yearly temperatures in Ecuador greater than in Springdale?" are acceptable questions. The others deal with subjectivity. </span>
1) Compund Ir (x) O(y)
2) Mass of iridium = mass of crucible and iridium - mass of crucible = 39.52 g - 38.26 g = 1.26 g
3) Mass of iridium oxide = mass of crucible and iridium oxide - mass of crucible = 39.73g - 38.26g = 1.47g
4) Mass of oxygen = mass of iridum oxide - mass of iridium = 1.47g - 1.26g = 0.21g
5) Convert grams to moles
moles of iridium = mass of iridium / molar mass of iridium = 1.26 g / 192.17 g/mol = 0.00656 moles
moles of oxygen = mass of oxygen / molar mass of oxygen = 0.21 g / 15.999 g/mol = 0.0131
6) Find the proportion of moles
Divide by the least of the number of moles, i.e. 0.00656
Ir: 0.00656 / 0.00656 = 1
O: 0.0131 / 0.00656 = 2
=> Empirical formula = Ir O2 (where 2 is the superscript for O)
Answer: Ir O2
2 hydrogen molecules to one oxygen molecule
Remember by H2O since O doesn’t have a number after it you know there is only one oxygen molecule
Formula unit mass is defined as the sum of the mass of all the atoms each multiplied its atomic masses that are present in the empirical formula of a compound. It is expressed in amu.
Atomic mass of calcium = 40 amu
Atomic mass of chlorine = 35.5 amu
Formula mass of CaCl2 = (1 x 40) + (2 x 35.5) = 111amu.
