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A chemical compound is found to have the...

A chemical compound is found to have the following composition :
`C=19.57%,Fe=15.2%,N=22.83%,K=42.39%`
Calculate the empirical formula of the compound. What will be its molecular formula if the molecular mass of the compound is 368 ? Name the compound.

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To solve the problem of determining the empirical formula and molecular formula of the given compound, we will follow these steps: ### Step 1: Convert the percentages to grams Assuming we have 100 grams of the compound, the composition in grams will be: - Carbon (C) = 19.57 g - Iron (Fe) = 15.2 g - Nitrogen (N) = 22.83 g - Potassium (K) = 42.39 g ### Step 2: Calculate the number of moles of each element To find the number of moles, we will use the formula: \[ \text{Number of moles} = \frac{\text{mass (g)}}{\text{molar mass (g/mol)}} \] Using the molar masses: - Molar mass of C = 12 g/mol - Molar mass of Fe = 56 g/mol - Molar mass of N = 14 g/mol - Molar mass of K = 39 g/mol Calculating the moles: - Moles of C = \(\frac{19.57}{12} = 1.63\) moles - Moles of Fe = \(\frac{15.2}{56} = 0.271\) moles - Moles of N = \(\frac{22.83}{14} = 1.63\) moles - Moles of K = \(\frac{42.39}{39} = 1.09\) moles ### Step 3: Find the simplest mole ratio To find the simplest ratio, we will divide each mole value by the smallest number of moles calculated: - Moles of C = \(\frac{1.63}{0.271} \approx 6\) - Moles of Fe = \(\frac{0.271}{0.271} = 1\) - Moles of N = \(\frac{1.63}{0.271} \approx 6\) - Moles of K = \(\frac{1.09}{0.271} \approx 4\) ### Step 4: Write the empirical formula From the simplest mole ratio, we can write the empirical formula as: \[ \text{Empirical formula} = K_4FeC_6N_6 \] ### Step 5: Calculate the empirical formula mass Now, we calculate the empirical formula mass: - Mass of K = \(4 \times 39 = 156\) g/mol - Mass of Fe = \(1 \times 56 = 56\) g/mol - Mass of C = \(6 \times 12 = 72\) g/mol - Mass of N = \(6 \times 14 = 84\) g/mol Total empirical formula mass = \(156 + 56 + 72 + 84 = 368\) g/mol ### Step 6: Determine the molecular formula Given that the molecular mass of the compound is also 368 g/mol, we can find the value of \(n\) using: \[ n = \frac{\text{Molecular mass}}{\text{Empirical formula mass}} = \frac{368}{368} = 1 \] Thus, the molecular formula is the same as the empirical formula: \[ \text{Molecular formula} = K_4FeC_6N_6 \] ### Step 7: Name the compound The compound is named potassium ferrocyanide. ### Final Answers: - Empirical formula: \(K_4FeC_6N_6\) - Molecular formula: \(K_4FeC_6N_6\) - Name of the compound: Potassium ferrocyanide ---

To solve the problem of determining the empirical formula and molecular formula of the given compound, we will follow these steps: ### Step 1: Convert the percentages to grams Assuming we have 100 grams of the compound, the composition in grams will be: - Carbon (C) = 19.57 g - Iron (Fe) = 15.2 g - Nitrogen (N) = 22.83 g - Potassium (K) = 42.39 g ...
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Knowledge Check

  • Empirical formula of a compound is CH_(2)O and its molecular mass is 90. The molecular formula of the compound is

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    D
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  • If the empirical formula of a compound is CH, What is a possible molecular formula for the compound?

    A
    `CH_(2)`
    B
    `C_(2)H_(6)`
    C
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