Question 3.2: Determine the following for an atom whose complete chemical ......
Determine the following for an atom whose complete chemical symbol is ^{26}_{12}Mg.
a. The total number of subatomic particles present in the atom
b. The total number of subatomic particles present in the nucleus of the atom
c. The total number of nucleons present in the atom
d. The total charge (including sign) associated with the nucleus of the atom
a. The mass number gives the combined number of protons and neutrons present. The atomic number gives the number of electrons present. Adding these two numbers together gives the total number of subatomic particles present. There are 38 subatomic particles present (26 + 12 = 38).
b. The nucleus contains all protons and all neutrons. The mass number (protons + neutrons), thus, gives the total number of subatomic particles present in the nucleus of an atom. There are 26 subatomic particles present in the nucleus.
c. A nucleon is any subatomic particle present in the nucleus. Thus, both protons and neutrons are nucleons. There are 26 such particles present in the nucleus. Parts b and c of this example are, thus, asking the same thing using different terminology.
d. The charge associated with a nucleus originates from the protons present. It will always be positive because protons are positively charged particles. The atomic number, 12, indicates that 12 protons are present. Thus, the nuclear charge is +12.