Problem 110 - Chemistry An Atoms First Approach

Question

Write the formula for each of the following compounds: a. chromium(III) hydroxide b. magnesium cyanide c. lead(IV) carbonate d. ammonium acetate

Step-by-Step Solution

Answer

The chemical formulas for the given compounds are: a. chromium(III) hydroxide: \[Cr(OH)_3\] b. magnesium cyanide: \[Mg(CN)_2\] c. lead(IV) carbonate: \[Pb(CO_3)_2\] d. ammonium acetate: \[(NH_4)(CH_3COO)\]

Step 1: a. chromium(III) hydroxide

1. Identify the cation and the anion Chromium(III) is the cation and has a charge of +3. Hydroxide (OH) is the anion and has a charge of -1. 2. Balance the charges To balance the charges in the compound, we need to find the lowest common multiple of the charges. In this case, it's 3. So, we need one chromium(III) ion and three hydroxide ions. 3. Write the formula The formula for chromium(III) hydroxide is: \[Cr(OH)_3\]

Step 2: b. magnesium cyanide

1. Identify the cation and the anion Magnesium (Mg) is the cation and has a charge of +2. Cyanide (CN) is the anion and has a charge of -1. 2. Balance the charges To balance the charges in the compound, we need the lowest common multiple of the charges, which in this case is 2. We need one magnesium ion and two cyanide ions. 3. Write the formula The formula for magnesium cyanide is: \[Mg(CN)_2\]

Step 3: c. lead(IV) carbonate

1. Identify the cation and the anion Lead(IV) is the cation and has a charge of +4. Carbonate (CO_3) is the anion and has a charge of -2. 2. Balance the charges To balance the charges in the compound, we need the lowest common multiple of the charges, which in this case is 4. We need one lead(IV) ion and two carbonate ions. 3. Write the formula The formula for lead(IV) carbonate is: \[Pb(CO_3)_2\]

Step 4: d. ammonium acetate

1. Identify the cation and the anion Ammonium (NH_4) is the cation and has a charge of +1. Acetate (CH_3COO) is the anion and has a charge of -1. 2. Balance the charges In this case, the charges are already balanced with one ammonium ion and one acetate ion. 3. Write the formula The formula for ammonium acetate is: \[(NH_4)(CH_3COO)\]