Write the molecular formulas of the compounds: aluminum nitrate

Write the molecular formulas of the compounds: aluminum nitrate, hydrogen sulfide acid, sodium hydroxide And calculate the mass fraction of aluminum and sulfur in aluminum sulfide Al2S3.

1) Let’s write down the formulas of the compounds:

aluminum nitrate: Al (NO3) 3;
hydrosulfuric acid: H2S;
sodium hydroxide: NaOH.
2) 1. Calculate the relative molecular weight of aluminum sulfide:

Mr (Al2S3) = 2 * Ar (Al) + 3 * Ar (S) = 2 * 27 + 3 * 32 = 150;

2.Calculate the mass fraction of aluminum:

w (Al) = 2 * Ar (Al): Mr (Al2S3) = 54: 150 = 0.36 shares or 36%;

3. find the mass fraction of sulfur:

w (S) = 3 * Ar (S): Mr (Al2S3) = 96: 150 = 0.64 shares or 64%.

Answer: 36% Al, 64% S.