Question

isotope practice problems
element with same # protons, and # of neutrons.
the number next to isotopes signify mass #
for the isotopes below, fill in the blanks with number of protons, neutrons, electrons, name, etc.
sodium - 23 sodium - 24
11 11
12 13
11 11
nitrogen - 14 nitrogen - 15
number of protons 7 7
number of neutrons 7 8
number of electrons 7 7

26
28 31

number of protons 48
number of neutrons 64 66
number of electrons

number of protons
number of neutrons 44 46
number of electrons 35

3 5
4

an atom contains 15 protons and 17 neutrons. how many electrons does this atom have and what is the atomic number?
number of electrons
atomic number
the atomic masses of two isotopes of zinc are 64 and 66. if zinc has 27 electrons, what is the number of protons and neutrons in each isotope?
zinc - 64 number of protons
number of neutrons
zinc - 66 number of protons
number of neutrons

Explanation:

Step1: Recall atomic - structure rules

In a neutral atom, the number of electrons = number of protons, and the atomic number is equal to the number of protons. The mass number = number of protons+number of neutrons.

Step2: Solve for the atom with 15 protons

Since the number of electrons in a neutral atom is equal to the number of protons, the number of electrons is 15. The atomic number is equal to the number of protons, so the atomic number is 15.

Step3: Solve for Zinc isotopes

For a neutral atom, the number of protons is equal to the number of electrons. Given Zinc has 27 electrons, the number of protons in both Zinc - 64 and Zinc - 66 is 27.
For Zinc - 64, if the mass number is 64 and the number of protons is 27, then the number of neutrons is $64 - 27=37$.
For Zinc - 66, if the mass number is 66 and the number of protons is 27, then the number of neutrons is $66 - 27 = 39$.

Answer:

• Atom with 15 protons and 17 neutrons: Number of electrons: 15, Atomic number: 15
• Zinc - 64: Number of protons: 27, Number of neutrons: 37
• Zinc - 66: Number of protons: 27, Number of neutrons: 39