Answer:
Iron gains three electrons.
The atomic structure of the atom contains 9 positively charged particles (protons) and 10 neutrally charged particles (neutrons) in the center of the atom in a clump called the nucleus. Those 9 negatively charged particles (electrons) are moving around outside of the nucleus.
There are 10 neutral charges, because the mass of 19 comes from the number of neutral charges plus the number of positive charges.
To calculate the number of neutral charges, subtract the positive charges from the mass (19 - 9), and you get the number of neutral charges (10).
Answer:
B. CA, 14
Explanation:
Atoms of elements contain small particles known as electrons, neutrons, and protons. The nucleus of an atom is made up of neutrons and protons which are at the center of the atom. Electrons on the other hand surrounds the nucleus. Electron has negative charge while proton has a positive charge. The number of neutrons is equivalent to the number of protons . In addition, the number of protons is equal to mass number minus the number of electrons.
For the compound 
, it can be broken down into 
and 
. Its ion has a mass of 34 and 18 electrons which means it has already lost 2 electrons.
Therefore:
For the given element, the number of electrons is 18+2 = 20 electrons.
The number of protons = 34 - 20 = 14.
And the number of neutrons is 14.
Only option B has the correct answer.
I hope you are able to find your answer through the guidance of this site as I have yet to cover this topic in chemistry: http://scientifictutor.org/1021/chem-how-to-convert-between-grams-and-molecules/
