Problem 111 - Chemistry: The Central Science

Question

Because many ions and compounds have very similar names, there is great potential for confusing them. Write the correct chemical formulas to distinguish between (a) calcium sulfide and calcium hydrogen sulfide, (b) hydrobromic acid and bromic acid, (c) aluminum nitride and aluminum nitrite, (d) iron(II) oxide and iron(III) oxide, (e) ammonia and ammonium ion, (f) potassium sulfite and potassium bisulfite, (g) mercurous chloride and mercuric chloride, (h) chloric acid and perchloric acid.

Step-by-Step Solution

Answer

The correct chemical formulas for the given ions and compounds are: (a) \(CaS\) and \(Ca(HS)_2\) (b) \(HBr\) and \(HBrO_3\) (c) \(AlN\) and \(Al(NO_2)_3\) (d) \(FeO\) and \(Fe_2O_3\) (e) \(NH_3\) and \(NH_4^+\) (f) \(K_2SO_3\) and \(KHSO_3\) (g) \(Hg_2Cl_2\) and \(HgCl_2\) (h) \(HClO_3\) and \(HClO_4\)

Step 1: Pair (a): Calcium Sulfide and Calcium Hydrogen Sulfide

To write the correct chemical formulas, we need to identify the correct elements and their charges: 1. Calcium (Ca) has a charge of +2. 2. Sulfide (S) has a charge of -2. 3. Hydrogen Sulfide (HS) has a charge of -1. Now we can write the chemical formulas: 1. Calcium Sulfide: \(CaS\) 2. Calcium Hydrogen Sulfide: \(Ca(HS)_2\)

Step 2: Pair (b): Hydrobromic Acid and Bromic Acid

For these acids, firstly identify the corresponding anions: 1. Bromide (Br-) for Hydrobromic Acid 2. Bromate (BrO3-) for Bromic Acid Now, we can write the chemical formulas: 1. Hydrobromic Acid: \(HBr\) 2. Bromic Acid: \(HBrO_3\)

Step 3: Pair (c): Aluminum Nitride and Aluminum Nitrite

We have Aluminum (Al) with a charge of +3 in both cases. The anions are: 1. Nitride (N) with a charge of -3. 2. Nitrite (NO2-) with a charge of -1. Now we can write the chemical formulas: 1. Aluminum Nitride: \(AlN\) 2. Aluminum Nitrite: \(Al(NO_2)_3\)

Step 4: Pair (d): Iron(II) Oxide and Iron(III) Oxide

The oxidation states of Iron (Fe) differ in both cases: 1. Iron(II) has a charge of +2. 2. Iron(III) has a charge of +3. The Oxide ion (O) has a charge of -2 in both cases. Now we can write the chemical formulas: 1. Iron(II) Oxide: \(FeO\) 2. Iron(III) Oxide: \(Fe_2O_3\)

Step 5: Pair (e): Ammonia and Ammonium Ion

Here, we are dealing with a molecule and an ion: 1. Ammonia (NH3) is a neutral molecule. 2. Ammonium ion (NH4+) has a charge of +1. Now we can write the chemical formulas: 1. Ammonia: \(NH_3\) 2. Ammonium Ion: \(NH_4^+\)

Step 6: Pair (f): Potassium Sulfite and Potassium Bisulfite

Potassium (K) has a charge of +1 in both cases. The anions are: 1. Sulfite (SO3 2-) with a charge of -2. 2. Bisulfite (HSO3-) with a charge of -1. Now we can write the chemical formulas: 1. Potassium Sulfite: \(K_2SO_3\) 2. Potassium Bisulfite: \(KHSO_3\)

Step 7: Pair (g): Mercurous Chloride and Mercuric Chloride

The oxidation states of Mercury (Hg) differ in both cases: 1. Mercurous (I) has a charge of +1. 2. Mercuric (II) has a charge of +2. The Chloride ion (Cl) has a charge of -1 in both cases. Now we can write the chemical formulas: 1. Mercurous Chloride: \(Hg_2Cl_2\) 2. Mercuric Chloride: \(HgCl_2\)

Step 8: Pair (h): Chloric Acid and Perchloric Acid

For these acids, we need to identify the corresponding anions first: 1. Chlorate (ClO3-) for Chloric Acid. 2. Perchlorate (ClO4-) for Perchloric Acid. Now, we can write the chemical formulas: 1. Chloric Acid: \(HClO_3\) 2. Perchloric Acid: \(HClO_4\)