Potassium pearls under paraffin oil. The large pearl measures 0.5 cm.
| Potassium | |
|---|---|
 | |
| Identification | |
Symbol |
K
|
Block |
s-block
|
Group |
Group 1
|
Period |
Period 4
|
| Atomic Information | |
Atomic Number |
19
|
Atomic Radius |
227 pm
|
Mass |
39.09
|
Category |
|
Standard state(298 K) |
Solid
|
Electronic Configuration |
[Ar]4s1
|
Electronegativity (Pauling) |
Unknown
|
Unknown
| |
First ionisation energy |
Unknown
|
| Physical Properties | |
Color |
Silvery-White
|
Melting Point |
336.7 K
|
Boiling Point |
1032 K
|
Density of solid |
Unknown
|
Unknown
| |
| Heat Properties | |
Enthalpy of fusion |
Unknown
|
Enthalpy of atomisation |
Unknown
|
Enthalpy of vaporisation |
Unknown
|
Potassium is the 19th element in the periodic table according to its atomic number. It belongs to the Alkali metal's category and is highly reactive. Elemental potassium is soft, silver-white and oxidizes rapidly in air and is very reactive with water, which generates sufficient heat to ignite the hydrogen produced in the reaction(causing further heavy reaction). It burns with a Lilac coloured flame. Due to its high reactivity , potassium is usually kept stored in parrafin /kerosene oil.
Discovery[]
- The text in this section is similar to a Wikipedia article but revised.
The English name for the element potassium comes from the word "potash" which refers to the plant ashes. Potash primarily consists of Potassium as plant ashes have almost no sodium content. While potash has been used since ancient times, it was not understood for most of its history to be a fundamentally different substance from sodium mineral salts. Georg Ernst Stahl obtained experimental evidence that led him to suggest the fundamental difference of sodium and potassium salts in 1702, and Henri Louis Duhamel du Monceau was able to prove this difference in 1736. The exact chemical composition of potassium and sodium compounds, and the status as chemical element of potassium and sodium, was not known then. Potassium metal was first isolated in 1807 in England by Sir Humphry Davy, who derived it from caustic potash (KOH) by the use of electrolysis of the molten salt with the newly discovered voltaic pile. Potassium was the first metal that was isolated by electrolysis.
| 3 Li |
| 11 Na |
| 19 K |
| 37 Rb |
| 55 Cs |
| 87 Fr |
| 1 H |
2 He | ||||||||||||||||
| 3 Li |
4 Be |
5 B |
6 C |
7 N |
8 O |
9 F |
10 Ne | ||||||||||
| 11 Na |
12 Mg |
13 Al |
14 Si |
15 P |
16 S |
17 Cl |
18 Ar | ||||||||||
| 19 K |
20 Ca |
21 Sc |
22 Ti |
23 V |
24 Cr |
25 Mn |
26 Fe |
27 Co |
28 Ni |
29 Cu |
30 Zn |
31 Ga |
32 Ge |
33 As |
34 Se |
35 Br |
36 Kr |
| 37 Rb |
38 Sr |
39 Y |
40 Zr |
41 Nb |
42 Mo |
43 Tc |
44 Ru |
45 Rh |
46 Pd |
47 Ag |
48 Cd |
49 In |
50 Sn |
51 Sb |
52 Te |
53 I |
54 Xe |
| 55 Cs |
56 Ba |
* | 72 Hf |
73 Ta |
74 W |
75 Re |
76 Os |
77 Ir |
78 Pt |
79 Au |
80 Hg |
81 Tl |
82 Pb |
83 Bi |
84 Po |
85 At |
86 Rn |
| 87 Fr |
88 Ra |
** | 104 Rf |
105 Db |
106 Sg |
107 Bh |
108 Hs |
109 Mt |
110 Ds |
111 Rg |
112 Cn |
113 Nh |
114 Fl |
115 Mc |
116 Lv |
117 Ts |
118 Og |
| 119 Uue |
120 Ubn |
*** | 158 Ups |
159 Upo |
160 Upe |
161 Uhn |
| * | 57 La |
58 Ce |
59 Pr |
60 Nd |
61 Pm |
62 Sm |
63 Eu |
64 Gd |
65 Tb |
66 Dy |
67 Ho |
68 Er |
69 Tm |
70 Yb |
71 Lu |
| ** | 89 Ac |
90 Th |
91 Pa |
92 U |
93 Np |
94 Pu |
95 Am |
96 Cm |
97 Bk |
98 Cf |
99 Es |
100 Fm |
101 Md |
102 No |
103 Lr |