Many of the elements on the periodic table will always form ions that have the same charge. The alkali metals (shown in yellow) always form +1 ions. The alkaline earth metals (red) always form +2 ions. The halogens (blue) always form -1 ions.
Moles of ammonium sulfate = 26.42/molar mass of (NH4)2SO4
= 26.42/132.14 = 0.19 mole.
Molarity = moles of ammonium sulfate/volume of solution
= 0.19/50x10^-3
= 3.8M
Courtney’s in minerals can vary due to impurities but is usually diagnostic we determine the relative hardness of minerals using a scale diversity bye mineralogists Freidrich Mohs The scale assigned hardness Tuten common index minerals and is based up on the ability of one mineral to scratch another
