Which of the following properties are associated with transition metals?

Explanation

Correct option is D. The answer is all of these. Transition metals are known for their characteristic colors, their ability to form complexes, and their use as catalysts. Color: The colors of transition metal compounds are due to the presence of unpaired electrons in the d orbitals. These electrons can absorb certain wavelengths of light, which gives the compound its characteristic color. For example, copper(II) sulfate is blue because it absorbs red light. Complex formation: Transition metals can form complexes with other molecules or ions. A complex is a molecule or ion that contains a central metal atom or ion bonded to a group of other atoms or ions. The ability of transition metals to form complexes is due to the presence of vacant d orbitals that can accept electrons from other molecules or ions. Catalytic activity: Transition metals are often used as catalysts. A catalyst is a substance that speeds up a chemical reaction without being consumed in the reaction. Transition metals can act as catalysts because they can change the electronic structure of the reactants, which makes the reaction easier to happen. In addition to these three properties, transition metals are also known for their high melting points, their high densities, and their ability to conduct heat and electricity.