which is the formula mass of na2so4?\n119.06 amu\n125.98 amu\n142.05 amu\n174.12 amu

Explanation:

Step1: Identify atomic masses

Atomic mass of Na = 22.99 amu, S = 32.07 amu, O = 16.00 amu.

Step2: Calculate mass of Na atoms

There are 2 Na atoms in Na₂SO₄, so mass of Na atoms = 2×22.99 = 45.98 amu.

Step3: Calculate mass of S atom

There is 1 S atom, so mass of S atom = 32.07 amu.

Step4: Calculate mass of O atoms

There are 4 O atoms, so mass of O atoms = 4×16.00 = 64.00 amu.

Step5: Calculate formula mass

Formula mass of Na₂SO₄ = 45.98+32.07 + 64.00 = 142.05 amu.

Answer:

142.05 amu