What is the mass of 0.7891 mol of ferric oxide (fe2o3)?

The mass  of 0.7891 mol  of  ferric  oxide (Fe2O3)  is  125.94 grams

 calculation

mass of Fe2O3 is calculated using   moles   Fe2O3/ molar  mass of Fe2O3  formula

moles of Fe2O3  = 0.7891  moles

molar  mass  of Fe2O3=   (55.8 x2)  + (16 x3)  =159.6 g/mol

mass is therefore =0.7891 mol  x 159.6 g/mol=125.94 grams

- calcium has greater affinity to bond with electron receptors than hydrogen does and hence, it has the ability to replace hydrogen in most of its compounds.

- lithium has 2 valence electrons in the product because it can make only 1 bond with hydrogen. beryllium has 4 valence electrons in the product because it can only make 2 bonds. it has fewer electrons than neon and can react with electron donors. each hydrogen has 2 valence electrons, the same as helium.

- the covalent bond formed between carbon and hydrogen is polar because carbon is more electronegative than hydrogen and it attracts the bonded electron pair closer to itself, thus giving hydrogen a partial positive charge.

- a hydrogen bond is a relatively weak bond that hydrogen atoms make with the electronegative atoms nitrogen, oxygen or fluorine.

so the best choice is a.) 2 calcium (ca) atoms

the positions which points up in upward carbon and down in downward carbon are axial

and vice versa holds true for equatorial positions

so the correct answer with labelled diagram will be