Question

atomic structure worksheet 2
the atomic number of an element is the number of protons in the nucleus of an atom. the mass number is the total number of protons plus neutrons in the nucleus of an atom. use the periodic table to help you complete the chart below. remember to round the atomic mass to the nearest whole number to get the mass number if the number of neutrons is not given.

name of element	symbol of element	atomic number	mass number	number of protons	number of neutrons	number of electrons
iron-56				26
aluminum-27						13
carbon-12			12
hydrogen-1			1
phosphorus31					16
arsenic-75						33
neon-20				10
potassium-39	k
cobalt-59		27
iodine-127					74
lead-207			207
oxygen-16				8
zinc-66		30
chromium-52						24
barium-137			137
silver- 108					61
gold-207				79

Explanation:

Step1: Iron-56: Symbol=Fe, Atomic#=26, Mass#=56, Neutrons=30, Electrons=26

Atomic number=protons=26; Symbol=Fe; Neutrons=56-26=30; Electrons=protons=26

Step2: Aluminum-27: Symbol=Al, Atomic#=13, Mass#=27, Protons=13, Neutrons=14

Electrons=13=protons; Atomic#=13; Symbol=Al; Neutrons=27-13=14

Step3: Carbon-12: Symbol=C, Atomic#=6, Protons=6, Neutrons=6, Electrons=6

Atomic#=6=protons; Symbol=C; Neutrons=12-6=6; Electrons=6

Step4: Hydrogen-1: Symbol=H, Atomic#=1, Protons=1, Neutrons=0, Electrons=1

Atomic#=1=protons; Symbol=H; Neutrons=1-1=0; Electrons=1

Step5: Phosphorus-31: Symbol=P, Atomic#=15, Mass#=31, Protons=15, Electrons=15

Protons=31-16=15; Atomic#=15; Symbol=P; Electrons=15

Step6: Arsenic-75: Symbol=As, Atomic#=33, Mass#=75, Protons=33, Neutrons=42

Electrons=33=protons; Atomic#=33; Symbol=As; Neutrons=75-33=42

Step7: Neon-20: Symbol=Ne, Atomic#=10, Mass#=20, Neutrons=10, Electrons=10

Protons=10; Symbol=Ne; Neutrons=20-10=10; Electrons=10

Step8: Potassium-39: Atomic#=19, Mass#=39, Protons=19, Neutrons=20, Electrons=19

Atomic#=19=protons; Neutrons=39-19=20; Electrons=19

Step9: Cobalt-59: Symbol=Co, Mass#=59, Protons=27, Neutrons=32, Electrons=27

Atomic#=27=protons; Symbol=Co; Neutrons=59-27=32; Electrons=27

Step10: Iodine-127: Symbol=I, Atomic#=53, Mass#=127, Protons=53, Electrons=53

Protons=127-74=53; Atomic#=53; Symbol=I; Electrons=53

Step11: Lead-207: Symbol=Pb, Atomic#=82, Protons=82, Neutrons=125, Electrons=82

Atomic#=82=protons; Symbol=Pb; Neutrons=207-82=125; Electrons=82

Step12: Oxygen-16: Symbol=O, Atomic#=8, Mass#=16, Neutrons=8, Electrons=8

Protons=8; Symbol=O; Neutrons=16-8=8; Electrons=8

Step13: Zinc-66: Symbol=Zn, Mass#=66, Protons=30, Neutrons=36, Electrons=30

Atomic#=30=protons; Symbol=Zn; Neutrons=66-30=36; Electrons=30

Step14: Chromium-52: Symbol=Cr, Atomic#=24, Mass#=52, Protons=24, Neutrons=28

Electrons=24=protons; Atomic#=24; Symbol=Cr; Neutrons=52-24=28

Step15: Barium-137: Symbol=Ba, Atomic#=56, Protons=56, Neutrons=81, Electrons=56

Atomic#=56=protons; Symbol=Ba; Neutrons=137-56=81; Electrons=56

Step16: Silver-108: Symbol=Ag, Atomic#=47, Mass#=108, Protons=47, Electrons=47

Protons=108-61=47; Atomic#=47; Symbol=Ag; Electrons=47

Step17: Gold-207: Symbol=Au, Atomic#=79, Mass#=207, Neutrons=128, Electrons=79

Protons=79; Symbol=Au; Neutrons=207-79=128; Electrons=79

Answer:

Name of Element	Symbol of Element	Atomic Number	Mass Number	Number of Protons	Number of Neutrons	Number of electrons
Iron-56	Fe	26	56	26	30	26
Aluminum-27	Al	13	27	13	14	13
Carbon-12	C	6	12	6	6	6
Hydrogen-1	H	1	1	1	0	1
Phosphorus-31	P	15	31	15	16	15
Arsenic-75	As	33	75	33	42	33
Neon-20	Ne	10	20	10	10	10
Potassium-39	K	19	39	19	20	19
Cobalt-59	Co	27	59	27	32	27
Iodine-127	I	53	127	53	74	53
Lead-207	Pb	82	207	82	125	82
Oxygen-16	O	8	16	8	8	8
Zinc-66	Zn	30	66	30	36	30
Chromium-52	Cr	24	52	24	28	24
Barium-137	Ba	56	137	56	81	56
Silver-108	Ag	47	108	47	61	47
Gold-207	Au	79	207	79	128	79