Question

originally, chemical substances were named based on their origins or properties, leading to a chaotic assortment of common names. the adoption of the international union of pure and applied chemistry (iupac) system in 1919 not only provided names that reveal a substances composition but also standardized naming across the field.
the common name and iupac names for three ionic compounds are given below.

common name	iupac name	uses
limestone	calcium carbonate	cement production and antacid tablets
fluorite	calcium fluoride	optical lens production

label each image with the chemical formula for the substance indicated below.
click each dot on the image to select an answer.
quicklime
limestone
fluorite

Explanation:

Step1: Recall ionic - compound formula rules

For calcium oxide, calcium has a + 2 charge ($Ca^{2 + }$) and oxygen has a - 2 charge ($O^{2 - }$). The formula is $CaO$ as the charges balance out.

Step2: Determine calcium carbonate formula

Calcium ($Ca^{2 + }$) and carbonate ($CO_{3}^{2 - }$) combine in a 1:1 ratio to balance charges, so the formula is $CaCO_{3}$.

Step3: Find calcium fluoride formula

Calcium ($Ca^{2 + }$) and fluoride ($F^{-}$) combine. To balance the + 2 charge of calcium, two fluoride ions are needed, so the formula is $CaF_{2}$.

Answer:

Quicklime: $CaO$
Limestone: $CaCO_{3}$
Fluorite: $CaF_{2}$