Answer:
The density of the substance is 3.9 grams per cubic centimeter.
Explanation:
Given mass=27.3 grams
volume=7 cubic centimeter
We need to find the density.
Density of a substance can be calculated by dividing mass of substance by volume of a substance
Hence Density of the substance is 
.
The answer is sodium chloride
Ionization energy = the amount of energy it takes for an atom to lose an electron
Remember that the nucleus is positively charged and the electrons are negatively charged. Because those opposite charges attract, the nucleus is pulling the electron towards it and so, the closer an electron is to the nucleus of an atom, the stronger it is being pulled.
Now remember that as more electrons are added to match the number of protons, the shells fill up and each new shell that is made to accommodate for the electrons is further away from the nucleus. That means that the more electrons are in an atom, the more shells there are, and as the shells get further away from the nucleus, the electrons in those shells are pulled with much less force than electrons in the closer shells.
Now all that's left to remember is that as you go down the groups, the elements have bigger numbers of protons and so they have more electrons and so more shells.
Ta da!! Hope that helps!! :D
Answer:
1. The core electrons are 10
2. The valence electrons are 8
Explaination:
Core electrons are electrons located in the inner shells of and atom.
Valence electrons are electrons located on the outermost shell of an atom
From the question given above, we obtained:
Ar (18) => [Ne] 3s²3p⁶
Recall
Ne (10) => 1s² 2s²2p⁶
Therefore,
Ar (18) => [1s² 2s²2p⁶] 3s²3p⁶
From the above illustration,
Inner shell (core shell) => 1s² 2s²2p⁶
Outermost shell (valence shell) => 3s²3p⁶
1. Determination of the core electrons
Inner shell (core shell) => 1s² 2s²2p⁶
Core electrons = 2 + 2 + 6
Core electrons = 10
2. Determination of the valence electrons
Outermost shell (valence shell) => 3s²3p⁶
Valence electron = 2 + 6
Valence electron = 8
