The correct answer is option A. Energy cannot be created during an ordinary chemical reaction. There is no such thing as an ordinary chemical reaction. Energy cannot be created or destroyed this is according to the law of conservation of energy. It can only be transformed from one form to another form.
Mendeleev’s was organized in atomic mass whereas the modern periodic table is organized by atomic number
<>"The researchers stress that their approach does not offer a complete roadmap for sustainable development, but does provide an important element by identifying critical planetary boundaries. "Human pressure on the Earth system has reached a scale where abrupt global environmental change can no longer be excluded."<>
