Question

identify the symbol for each element
1 oxygen o
2 hydrogen h
3 chlorine cl
4 sodium na
5 fluorine f
6 carbon c
7 helium he
8 nitrogen n
9 copper cu
10 sulfur s
11 magnesium mg
12 manganese mn
13 neon ne
14 bromine br
15 phosphorus p
16 silver ag
17 lead pb
18 iron fe
19 calcium ca
20 potassium k
fill in the chart below. the first row has been completed as an example.

element	symbol	atomic number	period	group
sodium	na	11	3	1
	o
krypton		79	4	7

give an atom with the following characteristics.
a halogen
b chalcogen
c alkali metal
d actinide series
e lanthanide series
f alkaline earth metal
g transition metal
h nobel gas

Explanation:

Step1: Recall element symbols

Oxygen is O, Hydrogen is H, Chlorine is Cl, Sodium is Na, Fluorine is F, Carbon is C, Helium is He, Nitrogen is N, Copper is Cu, Sulfur is S, Magnesium is Mg, Manganese is Mn, Neon is Ne, Bromine is Br, Phosphorus is P, Silver is Ag, Lead is Pb, Iron is Fe, Calcium is Ca, Potassium is K.

Step2: Fill in the chart for Sodium

The symbol for Sodium is Na, atomic number is 11, period is 3, group is 1.

Step3: Fill in the chart for Krypton

The symbol for Krypton is Kr, atomic number is 36 (not 79 as 79 is for Gold), period is 4, group is 18.

Step4: Provide atoms for each category

a. Halogen: Chlorine (Cl)
b. Chalcogen: Oxygen (O)
c. Alkali metal: Sodium (Na)
d. Actinide series: Uranium (U)
e. Lanthanide series: Cerium (Ce)
f. Alkaline Earth metal: Calcium (Ca)
g. Transition metal: Iron (Fe)
h. Nobel gas: Krypton (Kr)

Answer:

Element	Symbol	Atomic Number	Period	Group
Oxygen	O	8	2	16
Krypton	Kr	36	4	18

a. Chlorine (Cl)
b. Oxygen (O)
c. Sodium (Na)
d. Uranium (U)
e. Cerium (Ce)
f. Calcium (Ca)
g. Iron (Fe)
h. Krypton (Kr)