vi. Which element is not suitable to form H -bond? (a) Cl (b) F (c) O (d) vii. During the metal extraction from ore, froth flotation process is performed for (a) Sulphide ore (b) Carbonate ore (c) Oxide ore (d) Sulphate ore viii. Proximate analysis of coal involves the estimation of \% of (a) carbon, hydrogen (b) moisture content, volatile matter, ash, free carbon (c) moisture content (d) volatile m

Let's analyze each question step by step: ### vi. Which element is not suitable to form H-bond? To determine which element is not suitable for forming hydrogen bonds, we need to consider the elements listed: - **Cl (Chlorine)**: Chlorine can form hydrogen bonds, but it is not as effective as F and O. - **F (Fluorine)**: Fluorine is highly electronegative and is one of the best elements for forming hydrogen bonds. - **O (Oxygen)**: Oxygen is also highly electronegative and is well-known for forming hydrogen bonds. **Conclusion**: The element that is least suitable for forming hydrogen bonds among the options is **(a) Cl**. ### vii. During the metal extraction from ore, froth flotation process is performed for: The froth flotation process is primarily used for the separation of minerals based on their hydrophobic properties. Let's analyze the options: - **(a) Sulphide ore**: Froth flotation is commonly used for sulfide ores, as they can be treated to become hydrophobic. - **(b) Carbonate ore**: This type of ore is generally not treated using froth flotation. - **(c) Oxide ore**: Oxide ores are typically not suitable for froth flotation. - **(d) Sulphate ore**: Similar to carbonate and oxide ores, sulfate ores are not usually treated with froth flotation. **Conclusion**: The correct answer is **(a) Sulphide ore**. ### viii. Proximate analysis of coal involves the estimation of % of: Proximate analysis of coal is a method used to determine the composition of coal. The components typically analyzed include: - **(a) carbon, hydrogen**: This is not a complete representation of proximate analysis. - **(b) moisture content, volatile matter, ash, free carbon**: This option includes the main components measured in proximate analysis. - **(c) moisture content**: This is only one part of proximate analysis. - **(d) volatile matter**: This is also just one part of proximate analysis. **Conclusion**: The correct answer is **(b) moisture content, volatile matter, ash, free carbon**. ### Summary of Answers: - vi: (a) Cl - vii: (a) Sulphide ore - viii: (b) moisture content, volatile matter, ash, free carbon