Answer:
It is Likely to Be Sodium (Na) coz as You Down The group the reactivity increase
<span>You can answer this question by getting the atomic number and atomic mass of Oxygen from a periodic table. There you will find that the atomic number is 8, that means, by definition, that it has 8 protons. This is, because atomic number is defined as the number of protons of an element. Given that the atom is neutral, that implies that the atoms have the same number of electrons than protons. So you already know that the oxygen atoms has 8 protons and 8 electrons. The number of neutrons can vary, which is what defines the isotopes. Given that the atomic mass of oxygen is 15.999, that means that most atoms of oxygen has 8 neutrons (8 protons +8 neutrons = 16 atomic mass). But you can not be sure that a specific atom of oxygen has 8 neutrons, nevertheless, given that the other options are discarded (because they do not have 8 protons and 8 electrons), the only correct answer is the option A. 8 protons, 8 electrons, and 8 neutrons.</span>
Answer:
C.) 35
Explanation:
The mass is made up of the total protons and neutrons in an atom. Protons and neutrons both have a mass of 1 amu. Electrons are not included in this measurement because they have an insignificant mass (practically 0).
(17 protons x 1 amu) + (18 neutrons x 1 amu) = 35 amu
Therefore, if an atom contains 17 protons and 18 neutrons, the mass should be 35 amu.
Explanation:
Because a large amount of energy is required to break the strong inter-ionic attraction.
CaS => Ca2+ & S2-
