Question

classify each of the compounds as a molecule or a salt. molecule: c₃h₈, k₂co₃, cabr₂. salt: so₃, ch₂o, nacl

Explanation:

Step1: Recall definitions

A molecule is a group of two or more atoms held together by chemical bonds. A salt is an ionic compound formed by the reaction of an acid and a base.

Step2: Analyze $C_3H_8$

Propane ($C_3H_8$) is composed of non - metal atoms bonded covalently, so it is a molecule.

Step3: Analyze $K_2CO_3$

Potassium carbonate ($K_2CO_3$) is an ionic compound made up of potassium cations ($K^+$) and carbonate anions ($CO_3^{2 - }$), so it is a salt.

Step4: Analyze $CaBr_2$

Calcium bromide ($CaBr_2$) is an ionic compound with calcium cations ($Ca^{2+}$) and bromide anions ($Br^-$), so it is a salt.

Step5: Analyze $SO_3$

Sulfur trioxide ($SO_3$) consists of non - metal atoms bonded covalently, so it is a molecule.

Step6: Analyze $CH_2O$

Formaldehyde ($CH_2O$) has non - metal atoms bonded covalently, so it is a molecule.

Step7: Analyze $NaCl$

Sodium chloride ($NaCl$) is an ionic compound with sodium cations ($Na^+$) and chloride anions ($Cl^-$), so it is a salt.

Answer:

Molecule: $C_3H_8$, $SO_3$, $CH_2O$
Salt: $K_2CO_3$, $CaBr_2$, $NaCl$