Answer:
a. ionic, 211.62g/mol
b. molecular, 149g/mol
c. molecular, 342g/mol
Step-by-step explanation:
Ionic Compound: These are compounds (2 or more elements) where atoms of the element have lost or gained electrons, thus they are ions, thus the name ionic. An easy way to identify ionic compounds is to see if there are any metals. Metals tend to give up their electron to a non-metal. It maybe helpful to familiarize which parts of the periodic table have metals and non-metals.
Molecular Compounds: These are compounds (2 or more elements) that are neutral. An easy way to identify them is that the compound is made up of just non-metals.
Molar Mass is the masses of each individual element in the compound. Refer to the periodic table for the masses and add them up carefully, remember to multiply their mass based on how many molecules there are in the compound, like for a, we can find the mass of NO3, but we need to multiply it by 2 since we have 2 molecules of NO3.
a. Sr(NO3)2
Sr= 87.62
NO3= 14 + (3 x 16)= 62
Sr + 2 (NO3)
87.62 + (2 x 62)= 211.6
b. (NH4)3PO4
NH4= 14 + 4 = 18
PO4= 30.97 + (4 x 16)= 94.9
(NH4 x 3) + PO4
(18 x 3) + 94.9 = 149
c. C12H22O11
(12 x C) + (22 x H) + (11 x O)
(12 x 12) + (22 x 1) + (11 x 16)
144 + 22 + 176= 342