0.50 Molar means 0.50 moles/liter
(.5 moles/liter)/3.5 moles= 1/7 Liters
Less compassionate around the chocolate
-1 charge = the atom has gained one electron
9+1=10
The units tell you:
g/cm³ = Mass (in grams) per (divided by) Volume (in cm³);
So:
109/24 = 4.54166..... ⇒ 4.54 g/cm³.
Always look at the units.
Just like for speed, you might have m/s so this is:
Distance (in meters) per (divided by) Time (in seconds).
