25 POINTS FOR SCIENCE! PLEASE HELP

1. 9.36 moles S

2. 0.213 moles Al

Given

Reaction

2Al+3S⇒Al₂S₃

Required

moles of S

moles of Al

Solution

The reaction coefficient in a chemical equation shows the mole ratio of the compounds involved in the reaction (reactants or products)

From equation, mol ratio of Al₂S₃ : S = 1 : 3, so mol S :

= 3/1 x mol Al₂S₃

= 3/1 x 3.12

= 9.36 moles S

From equation, mol ratio of Al : S = 2 : 3, so mol Al :

= 2/3 x mol S

= 2/3 x 0.32

= 0.213 moles Al

answer: atomic mass was originally used to arrange elements on the periodic table, but is no longer used to organize the modern version.

explanation:

originally atomic mass was used to arrange elements on the periodic table from left to right in a row. each column then shows similar properties of elements of a group.

in modern periodic table, the atoms are arranged in increasing atomic number. as atomic number represents the number of protons in an atom which is unique for every atom.