Question

periodic table worksheet
instructions: using the periodic table fill out the blanks in this table. assume all rows are for elements that are neutral and not ions.

element name | atomic symbol | atomic number | proton # | neutron # | electron # | mass # (amu)
carbon | c | 6 | 6 | 8 | 6 | 14
magnesium | mg | 12 | 12 | 12 | 12 | 24

	31	31	40	31
zr				40	89
	30	30	35	30
		42			98
w					183
			105	71
	95	95		95	243
cr			27
	83	83		83	209
	90	90	142	90
md					259
se
					80
	40	40	51	40

Answer:

To solve the periodic table worksheet, we use the following relationships for neutral atoms:

• Atomic Number = Proton # = Electron #
• Mass # (amu) = Proton # + Neutron #

Row 1: Carbon (C)

Step 1: Atomic Number (Z)

For neutral C, Atomic Number = Proton # = Electron #. From the table, Neutron # = 8, Mass # = 14.
Proton # = Mass # − Neutron # = \( 14 - 8 = 6 \). Thus, Atomic Number = 6, Electron # = 6.

Row 2: Magnesium (Mg)

Step 1: Proton #

Atomic Number = 12, so Proton # = 12, Electron # = 12.

Step 2: Neutron #

Mass # = 24, so Neutron # = \( 24 - 12 = 12 \).

Row 3: Element with Proton # = 31

Step 1: Atomic Number

Atomic Number = Proton # = 31, so Electron # = 31.

Step 2: Mass #

Mass # = Proton # + Neutron # = \( 31 + 40 = 71 \).
Element: Gallium (Ga) (Atomic Number 31).

Row 4: Zirconium (Zr)

Step 1: Proton #

Electron # = 40 (neutral), so Proton # = 40, Atomic Number = 40.

Step 2: Neutron #

Mass # = 89, so Neutron # = \( 89 - 40 = 49 \).

Row 5: Atomic Number = 30

Step 1: Proton #, Electron #

Proton # = 30, Electron # = 30.

Step 2: Mass #

Mass # = \( 30 + 35 = 65 \).
Element: Zinc (Zn) (Atomic Number 30).

Row 6: Proton # = 42

Step 1: Atomic Number, Electron #

Atomic Number = 42, Electron # = 42.

Step 2: Neutron #

Mass # = 98, so Neutron # = \( 98 - 42 = 56 \).
Element: Molybdenum (Mo) (Atomic Number 42).

Row 7: Tungsten (W)

Step 1: Atomic Number, Proton #, Electron #

Atomic Number = 74 (W has Z=74), so Proton # = 74, Electron # = 74.

Step 2: Neutron #

Mass # = 183, so Neutron # = \( 183 - 74 = 109 \).

Row 8: Electron # = 71

Step 1: Proton #, Atomic Number

Proton # = 71, Atomic Number = 71.

Step 2: Mass #

Mass # = \( 71 + 105 = 176 \).
Element: Lutetium (Lu) (Atomic Number 71).

Row 9: Atomic Number = 95

Step 1: Electron #

Electron # = 95 (neutral).

Step 2: Neutron #

Mass # = 243, so Neutron # = \( 243 - 95 = 148 \).
Element: Americium (Am) (Atomic Number 95).

Row 10: Chromium (Cr)

Step 1: Atomic Number, Proton #, Electron #

Atomic Number = 24 (Cr has Z=24), so Proton # = 24, Electron # = 24.

Step 2: Mass #

Mass # = \( 24 + 27 = 51 \).

Row 11: Atomic Number = 83

Step 1: Proton #, Electron #

Proton # = 83, Electron # = 83.

Step 2: Neutron #

Mass # = 209, so Neutron # = \( 209 - 83 = 126 \).
Element: Bismuth (Bi) (Atomic Number 83).

Row 12: Atomic Number = 90

Step 1: Proton #, Electron #

Proton # = 90, Electron # = 90.

Step 2: Mass #

Mass # = \( 90 + 142 = 232 \).
Element: Thorium (Th) (Atomic Number 90).

Row 13: Mendelevium (Md)

Step 1: Atomic Number, Proton #, Electron #

Atomic Number = 101 (Md has Z=101), so Proton # = 101, Electron # = 101.

Step 2: Neutron #

Mass # = 259, so Neutron # = \( 259 - 101 = 158 \).

Row 14: Selenium (Se)

Step 1: Atomic Number, Proton #, Electron #

Atomic Number = 34 (Se has Z=34), so Proton # = 34, Electron # = 34.

Step 2: Neutron #

Mass # = 80, so Neutron # = \( 80 - 34 = 46 \).

Row 15: Atomic Number = 40

Step 1: Element, Electron #

Element: Zirconium (Zr) (Z=40), Electron # = 40.

Step 2: Mass #

Mass # = \( 40 + 51 = 91 \).

Filled Table (Key Values):

Element Name	Atomic Symbol	Atomic Number	Proton #	Neutron #	Electron #	Mass # (amu)
Magnesium	Mg	12	12	12	12	24
Gallium	Ga	31	31	40	31	71
Zirconium	Zr	40	40	49	40	89
Zinc	Zn	30	30	35	30	65
Molybdenum	Mo	42	42	56	42	98
Tungsten	W	74	74	109	74	183
Lutetium	Lu	71	71	105	71	176
Americium	Am	95	95	148	95	243
Chromium	Cr	24	24	27	24	51
Bismuth	Bi	83	83	126	83	209
Thorium	Th	90	90	142	90	232
Mendelevium	Md	101	101	158	101	259
Selenium	Se	34	34	46	34	80
Zirconium	Zr	40	40	51	40	91

(Note: For each row, use the relationships \( \text{Atomic Number} = \text{Proton \#} = \text{Electron \#} \) and \( \text{Mass \#} = \text{Proton \#} + \text{Neutron \#} \) to fill blanks.)