Which one of the following pairs of metals constitutes the lightest metal and the heaviest metal, respectively?

Consider the following statements : 1. Statement I : Activated carbon is a good and an attractive tool to remove pollutants from effluent streams and to remediate contaminants from various industries. 2. Statement II : Activated carbon exhibits a large surface area and a strong potential for adsorbing heavy metals. 3. Statement III : Activated carbon can be easily synthesized from environmental wastes with high carbon content. Which one of the following is correct in respect of the above statements?

Consider the following: 1. Cigarette butts 2. Eyeglass lenses 3. Car tyres How many of them contain plastic?

Consider the following statements : 1. Statement I : Some rare earth elements are used in the manufacture of flat television screens and computer monitors. 2. Statement II : Some rare earth elements have phosphorescent properties. Which one of the following is correct in respect of the above statements?

What is the common characteristic of the chemical substances generally known as CL-20, HMX and LLM-105, which are sometimes talked about in media?

Consider the following statements : 1. Carbon fibres are used in the manufacture of components used in automobiles and aircrafts. 2. Carbon fibres once used cannot be recycled. Which of the statements given above is/are correct?