Find the Molecular mass of all atoms in the chemical formula and divide it with the mass of the sunstance to get the amount of moles
<h3><u>Answer;</u></h3>
= 9.45 × 10^23 molecules
<h3><u>Explanation; </u></h3>
The molar mass of Na2SO4 = 142.04 g/mol
Number of moles = mass/molar mass
= 223/142.04
= 1.57 moles
But;
1 mole = 6.02 × 10^23 molecules
Therefore;
1.57 moles = ?
= 1.57 × 6.02 × 10^23 molecules
<u>= 9.45 × 10^23 molecules </u>
There are 4 significant figures.
zeros after the decimal point are not significant
Neptune's atmosphere is composed up of many gases. These gases include Hydrogen (80%), Helium (19%), and Methane<span> (1.5%). Some of the minor gases include trace amounts of </span>Hydrogen Deuteride<span> and </span>Ethane<span>.</span>
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