Question 1: Explain why transition metal compounds often display vibrant colors and how this property is useful in environmental science.

Answer: Transition metal compounds display vibrant colors due to d-orbital electron transitions that absorb specific wavelengths of light. In environmental science, these colors help identify metal pollutants and monitor pollution levels.

Question 1: Define a colored compound in the context of transition metals.

Answer: A colored compound is a chemical substance containing transition metals that exhibits color due to electronic transitions within the d-orbitals when exposed to light.

Question 2: Describe the mechanism by which transition metals produce color in their compounds.

Answer: Transition metals produce color through d-d electron transitions that occur when electrons absorb specific wavelengths of light, exciting them to higher energy levels, which results in the observed color.

Question 1: A sample of copper sulfate solution shows a maximum absorption at 600 nm with an absorbance of 0.75 in a 1 cm cuvette. Calculate the concentration of copper sulfate if the molar absorptivity (ε) at this wavelength is 100 L mol^-1 cm^-1. (Use Beer's Law: A = εcl)

Answer: Concentration (c) = A / (ε × l) = 0.75 / (100 × 1) = 0.0075 mol/L

Question 1: List three safety precautions that should be followed when handling transition metal compounds in environmental testing.

Answer: Wear gloves and safety goggles to prevent skin and eye contact, work in a well-ventilated area or fume hood, and handle chemicals according to proper disposal protocols.

Question 2: Identify the variables involved in testing water samples for metal pollutants using colored compounds.

Answer: Variables include the concentration of metal ions in the water sample, pH level, temperature, and the exposure time to the reagent.

Question 1: A water sample tested for nickel ions shows a deep green color after adding a specific reagent. The absorbance at 520 nm was recorded as 0.65 in a 1 cm cuvette. If the molar absorptivity at this wavelength is 85 L mol^-1 cm^-1, estimate the concentration of nickel ions in the sample.

Answer: Concentration = 0.65 / (85 × 1) ≈ 0.00765 mol/L

Question 1: Explain how colored transition metal complexes are used in pollution detection and environmental monitoring.

Answer: Colored transition metal complexes act as indicators that change color in response to specific pollutants, allowing for easy detection and monitoring of environmental contamination.

Question 2: Describe one technological advancement that uses colored compounds of transition metals to improve environmental safety.

Answer: One advancement is the development of colorimetric sensors that detect heavy metal contamination in water. These sensors use transition metal complexes that change color in the presence of specific pollutants, providing rapid and visual indication of contamination levels, thereby improving response times and safety measures.