Suppose we have 100 g of each of the following substances. Which sample contain the greatest number of moles (F. W. = Formula Weight) A. HCI, F. W. = 36.5 B. H_2O, F. W. = 18.0 C. MgCO_3 F. W. = 84.3 D. AlCI_3, F. W. = 133.3 E. NaCl, F. W. = 58.4

100 g of water has the highest number of moles

Explanation:

Recall that the number of moles is obtained as given mass/formula weight

For HCl;

number of moles = 100g/36.5g/mol = 2.7 moles

For H2O;

number of moles = 100g/18g/mol = 5.5 moles

For MgCO3

number of moles = 100g/84.3 g/mol = 1.2 moles

For AlCl3

number of moles = 100g/133.3g/mol = 0.75 moles

For NaCl

number of moles = 100g/58.4 g/mol = 1.7 moles

a is the correct answer