---
title: "A student analyzes a hydrated coordination compound with the formula \\(\\text{K}_3[\\text{Fe}(\\text{C}_2\\text{O}_4)_3]\\cdot x\\text{H}_2\\text{O}\\). During quantitative oxidation in excess \\(\\text{O}_2\\), all the carbon atoms in the compound are converted to \\(\\text{CO}_2\\), so each mole of the hydrate produces \\(6\\) moles of \\(\\text{CO}_2\\). Heating a separate sample removes only the crystal water.  | Analysis | Initial mass of hydrate | Other measured mass | |—|—:|—:| | Quantitative oxidation | \\(0.491\\text{ g}\\) | \\(0.264\\text{ g of }\\text{CO}_2\\) collected | | Dehydration | \\(0.982\\text{ g}\\) | \\(0.874\\text{ g}\\) of anhydrous residue |  The molar masses of \\(\\text{CO}_2\\) and \\(\\text{H}_2\\text{O}\\) are \\(44.0\\text{ g mol}^{-1}\\) and \\(18.0\\text{ g mol}^{-1}\\), respectively. Which pair gives the experimental average molar mass of the hydrate and the theoretical mass of crystal water in the dehydration sample, respectively?"
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url: "https://nerd-notes.com/ubq/120105/"
date_modified: "2026-08-21T08:41:38+00:00"
---

# A student analyzes a hydrated coordination compound with the formula \(\text{K}_3[\text{Fe}(\text{C}_2\text{O}_4)_3]\cdot x\text{H}_2\text{O}\). During quantitative oxidation in excess \(\text{O}_2\), all the carbon atoms in the compound are converted to \(\text{CO}_2\), so each mole of the hydrate produces \(6\) moles of \(\text{CO}_2\). Heating a separate sample removes only the crystal water.

| Analysis | Initial mass of hydrate | Other measured mass |
|—|—:|—:|
| Quantitative oxidation | \(0.491\text{ g}\) | \(0.264\text{ g of }\text{CO}_2\) collected |
| Dehydration | \(0.982\text{ g}\) | \(0.874\text{ g}\) of anhydrous residue |

The molar masses of \(\text{CO}_2\) and \(\text{H}_2\text{O}\) are \(44.0\text{ g mol}^{-1}\) and \(18.0\text{ g mol}^{-1}\), respectively. Which pair gives the experimental average molar mass of the hydrate and the theoretical mass of crystal water in the dehydration sample, respectively?

A student analyzes a hydrated coordination compound with the formula \(\text{K}_3[\text{Fe}(\text{C}_2\text{O}_4)_3]\cdot x\text{H}_2\text{O}\). During quantitative oxidation in excess \(\text{O}_2\), all the carbon atoms in the compound are converted to \(\text{CO}_2\), so each mole of the hydrate produces \(6\) moles of \(\text{CO}_2\). Heating a separate sample removes only the crystal water.

| Analysis | Initial mass of hydrate | Other measured mass |
|---|---:|---:|
| Quantitative oxidation | \(0.491\text{ g}\) | \(0.264\text{ g of }\text{CO}_2\) collected |
| Dehydration | \(0.982\text{ g}\) | \(0.874\text{ g}\) of anhydrous residue |

The molar masses of \(\text{CO}_2\) and \(\text{H}_2\text{O}\) are \(44.0\text{ g mol}^{-1}\) and \(18.0\text{ g mol}^{-1}\), respectively. Which pair gives the experimental average molar mass of the hydrate and the theoretical mass of crystal water in the dehydration sample, respectively?

- **A.** \(491\text{ g mol}^{-1}\) and \(0.108\text{ g of }\text{H}_2\text{O}\)
- **B.** \(491\text{ g mol}^{-1}\) and \(0.216\text{ g of }\text{H}_2\text{O}\)
- **C.** \(545\text{ g mol}^{-1}\) and \(0.097\text{ g of }\text{H}_2\text{O}\)
- **D.** \(545\text{ g mol}^{-1}\) and \(0.195\text{ g of }\text{H}_2\text{O}\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/120105/*