Answer:
The mass of the nucleus is almost the same as the atom because a majority of the mass of an atom is stored in the nucleus.
The volume of an atom is larger than the nucleus. The nucleus is a tiny, concentrated area inside of the atom. Atoms are mostly empty space inside.
Explanation:
It decreases in volume, as the energy is lost.
Sodium has a noble gas configuration, plus a single high energy 3s1 electron. This electron is more stable when associated with more electronegative atoms and polyatomic ions. Therefore, sodium loses a single electron (losing a negative charge, granting the sodium atom a +1 charge). Positive and negative charges attract each other in order to balance out the charge (reach a low energy state), so two +1 sodium atoms need to associate with either two separate -1 charges, or a single -2 charge. The only polyatomic listed here that satisfies the -2 (formally written 2-) needed to attract both sodium atoms is the Carbonate ion, CO3(2-).
Steps of a scientific investigation include identifying a research question or problem, forming a hypothesis, gathering evidence, analyzing evidence, deciding whether the evidence supports the hypothesis, drawing conclusions, and communicating the results.
Answer:
The reaction in which heat is absorbed from the surrounding is called endothermic reaction.
so
I think it's answer is 2nd option.
