GROWTH DEVELOPMENT CHILD
SUMMATIVE ASSESSMENT
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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they are most reactive than alkali metals such as Na, K, they are insulators
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they are not good conductors of heat and electricity
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many are used as catalysts, they form coloured ions of different charges
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None of the above
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Detailed explanation-1: -The transition metals have the following physical properties in common: they are good conductors of heat and electricity. they can be hammered or bent into shape easily. they have high melting points (but mercury is a liquid at room temperature)
Detailed explanation-2: -The commonly used catalysts are Fe, Mo, Co, Cu, and Cr NPs. The carbon source can decompose into individual carbon atoms or atom pairs on the surface of these metal NPs at 700–1100 °C, and then form CNTs.
Detailed explanation-3: -Transition elements have vacant d orbitals. So, due to the presence of vacant d-orbital, they produce coloured compounds. Transition metal ions are not naturally coloured. They only become coloured when they form compounds with other ions or molecules.
Detailed explanation-4: -Transition metal coordination compounds with these ligands are yellow, orange, or red because they absorb higher-energy violet or blue light.