It’s mass because the law of conservation of mass states that in a chemical reaction mass is neither created nor destroyed.
The answer is N - N.
Purely covalent bond is formed by sharing electrons of atoms with same electronegativity to meet the octet rule (2 or 8 electrons in the valence shell).
Ne is a noble gas and has already 8 electrons in the valence shell, so it will not form a Ne - Ne bond.
Na is an alkaly metal with 1 electron in the valence shell and it does not form a true ionic bond but what is known a metallic bond.
N is a gas that forms a diatomic molecule N - N by sharing the valence electrons in a purely covalent bond.
Ni - O is a metal - non metal compound so it has a ionic character.
Hydrogen i think. the orbital of hydrogen is peculiar
Answer:
Every object you touch, see, taste, or smell during the day is a chemical, no matter what the signage says on some containers of “Contains no chemicals.” It would seem to me that knowing as much as possible about these objects would be of benefit to mankind, and hence chemistry becomes of great advantage to us all. The science of chemistry really has no disadvantages, but we humans can be at a disadvantage if we do not bother to learn, for example, that cyanide should not be part of your diet.
I hope it helps :) pls mark as the branliest
