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The tasks in the image are chemistry-related exercises. Here's a summary of what each task involves: **Задание 2. Получение оксида углерода(IV).** 1. **Получение CO₂:** You need to place a few pieces of chalk (calcium carbonate, CaCO₃) into a test tube and add some hydrochloric acid (HCl). This reaction will produce carbon dioxide (CO₂), water, and calcium chloride (CaCl₂). - **Chemical Reaction:** \[ \text{CaCO}_3 + 2 \text{HCl} \rightarrow \text{CaCl}_2 + \text{CO}_2 + \text{H}_2\text{O} \] 2. **Testing for CO₂:** Introduce a burning splint into the test tube. If the flame extinguishes, it indicates the presence of CO₂, which is heavier than air and does not support combustion. **Задание 3. Распознавание карбонатов.** This task involves identifying sodium (Na), calcium chloride (CaCl₂), and potassium carbonate (K₂CO₃) using three different labeled test tubes. 1. **Reactants Provided:** You are given hydrochloric acid and sodium hydroxide (NaOH). 2. **Objective:** Determine which reaction, when added to a carbonate, will produce CO₂ gas. 3. **Chemical Reactions:** - For a carbonate with an acid: \[ \text{Na}_2\text{CO}_3 + 2\text{HCl} \rightarrow 2\text{NaCl} + \text{CO}_2 + \text{H}_2\text{O} \] - For a carbonate with a base (like NaOH), there will be no reaction. By following these guidelines, you can perform these experiments and identify the substances based on the reactions observed.