Question

1. which of the following has the greatest mass (in grams)?

one mole of h₂o
one mole of p
one mole of h₂so₄
one mole of na
clear all

Explanation:

Step1: Recall molar mass concept

Molar mass (in g/mol) of a substance is numerically equal to its atomic or molecular mass. For 1 mole, mass (in grams) = molar mass (g/mol).

Step2: Calculate molar mass of \(H_2O\)

Atomic masses: \(H = 1\) g/mol, \(O = 16\) g/mol.
Molar mass of \(H_2O = 2\times1 + 16 = 18\) g/mol.

Step3: Molar mass of \(P\)

Atomic mass of \(P\) is 31 g/mol. So molar mass = 31 g/mol.

Step4: Molar mass of \(H_2SO_4\)

Atomic masses: \(H = 1\), \(S = 32\), \(O = 16\).
Molar mass = \(2\times1 + 32 + 4\times16 = 2 + 32 + 64 = 98\) g/mol.

Step5: Molar mass of \(Na\)

Atomic mass of \(Na\) is 23 g/mol. So molar mass = 23 g/mol.

Step6: Compare molar masses

18 ( \(H_2O\) ) < 23 ( \(Na\) ) < 31 ( \(P\) ) < 98 ( \(H_2SO_4\) ). So 1 mole of \(H_2SO_4\) has the greatest mass.

Answer:

one mole of \(H_2SO_4\)