Question

part ii. for each of the following isotopes, write the number of protons, neutrons, and electrons. assume all atoms are neutral.

	carbon - 12	carbon - 13	carbon - 14
# of protons	6	6
# of neutrons	12 - 6 =	13 - 6 =
# of electrons	6	6
	chromium - 58	chromium - 63
# of protons	24
# of neutrons	58 - 24 =
# of electrons
	sulfur - 23	sulfur - 25
# of protons
# of neutrons
# of electrons
	nitrogen - 15	nitrogen - 20
# of protons
# of neutrons
# of electrons

Explanation:

Step1: Recall atomic number property

The number of protons is equal to the atomic number of the element. Carbon has an atomic number of 6, chromium has an atomic number of 24, sulfur has an atomic number of 16 and nitrogen has an atomic number of 7.

Step2: Calculate number of neutrons

The number of neutrons = mass - number - number of protons.
For Carbon - 12: Neutrons = 12 - 6 = 6; For Carbon - 13: Neutrons = 13 - 6 = 7; For Carbon - 14: Neutrons = 14 - 6 = 8; For Chromium - 58: Neutrons = 58 - 24 = 34; For Chromium - 63: Neutrons = 63 - 24 = 39; For Sulfur - 23: Neutrons = 23 - 16 = 7; For Sulfur - 25: Neutrons = 25 - 16 = 9; For Nitrogen - 15: Neutrons = 15 - 7 = 8; For Nitrogen - 20: Neutrons = 20 - 7 = 13.

Step3: Determine number of electrons

Since atoms are neutral, the number of electrons is equal to the number of protons. So for all cases:
Carbon - 12: 6 electrons; Carbon - 13: 6 electrons; Carbon - 14: 6 electrons; Chromium - 58: 24 electrons; Chromium - 63: 24 electrons; Sulfur - 23: 16 electrons; Sulfur - 25: 16 electrons; Nitrogen - 15: 7 electrons; Nitrogen - 20: 7 electrons.

Isotope	# of Protons	# of Neutrons	# of Electrons
Carbon - 13	6	7	6
Carbon - 14	6	8	6
Chromium - 58	24	34	24
Chromium - 63	24	39	24
Sulfur - 23	16	7	16
Sulfur - 25	16	9	16
Nitrogen - 15	7	8	7
Nitrogen - 20	7	13	7

Answer:

Isotope	# of Protons	# of Neutrons	# of Electrons
Carbon - 13	6	7	6
Carbon - 14	6	8	6
Chromium - 58	24	34	24
Chromium - 63	24	39	24
Sulfur - 23	16	7	16
Sulfur - 25	16	9	16
Nitrogen - 15	7	8	7
Nitrogen - 20	7	13	7