Tin (Sn)

Stable isotopes of tin available from ISOFLEX

Isotope Z(p) N(n) Atomic Mass Natural Abundance Enrichment Level Chemical Form
Sn-112  50  62  111.904826 0.97%  99.60% Metal
Sn-114  50  64  113.902782 0.65%  71.00-87.10% Metal
Sn-115 50 65 114.903347 0.34% 51.00-69.00% Metal
Sn-116 50 66 115.901745 14.54% 96.60-99.50% Metal
Sn-117 50 67 116.902955 7.68% 87.00-97.50% Metal
Sn-118 50 68 117.901608 24.22% 99.50% Metal
Sn-119 50 69 118.903311 8.59% 90.50-97.40% Metal
Sn-119 50 69 118.903311 8.59% 90.30% Oxide
Sn-120 50 70 119.902198 32.59% 98.80-99.70% Metal
Sn-122 50 72 121.903441 4.63% 93.40-99.30% Metal
Sn-124 50 74 123.905274 5.79% 99.90% Metal

Request a Quote


Tin was known in ancient times and is mentioned in the Old Testament. Early metal workers found it too soft for most purposes, but when mixed with copper, it produced bronze, which was suitable for many handcrafted items, especially tools and weapons. Tin takes its name from the Anglo-Saxon word tin, and the symbol Sn derives from the Latin word stannum, meaning “tin.”

Tin is a silvery-white metal at ordinary temperatures, slowly changing to gray below 13.2 ºC; it is soft, malleable and somewhat ductile. Tin has two allotropic forms: white tin, the beta form, which has a tetragonal structure and a density of 7.28 g/cm3, its color slowly changing from white to gray when cooled below 13.2 º C, converts to gray tin, the alpha form, with a density of 5.75 g/cm3. The presence of small amounts of antimony or bismuth prevents this transformation from white to gray tin.

Tin is insoluble in water; soluble in HCl, H2SO4, aqua regia and alkalis; and slightly soluble in dilute nitric acid. At ordinary temperatures, tin is stable in air, actually forming a very thin protective oxide film. In powder form, and especially in the presence of moisture, it oxidizes. When heated with oxygen, it forms tin oxide. Tin reacts with all halogens to form their halides. Tin is attacked by concentrated acids; with dilute acids, the reaction may be slow or very slow. The metal readily reacts with hot concentrated hydrochloric acid and aqua regia, but more slowly with cold dilute hydrochloric acid. The reaction also is slow with hot dilute sulfuric acid, which dissolves the metal, particularly in the presence of an oxidizing agent. The reaction with nitric acid is also generally slow. Hot concentrated acid converts the metal to an insoluble hydrate tin oxide. Reactions are more rapid with moist sulfur dioxide or sulfurous acid, chlorosulfonic or pyrosulfuric acids. Organic acids — such as acetic, oxalic and citric acids — react slowly with the metal, particularly in the presence of air or an oxidizing agent. The metal is stable in dilute solutions of ammonia or sodium carbonate. Tin dissolves in solutions of oxidizing salts such as potassium chlorate or potassium persulfate. The metal does not react with neutral salts in aqueous solutions; however, it reacts slowly with neutral salts in air. The metal does not combine directly with hydrogen, nitrogen or ammonia gas.

Today, tin is used for plating steel to make “tin” cans for preserving food. Also, tin coats other metals to prevent corrosion. An important application of tin is to produce "float glass" (made by floating molten glass on molten tin) for windows. A number of tin alloys have wide industrial applications and include bronze, solder, Babbit metal, White metal, type metal, fusible metal and phosphor bronze. A tin-niobium alloy that is superconducting at low temperatures is used in the construction of super magnets. Tin is also used in wrapping foil and collapsible tubes.

All organic tin compounds are toxic.

Properties of Tin

Name Tin
Symbol Sn 
Atomic number 50 
Atomic weight 118.69 
Standard state Solid at 298 °K 
CAS Registry ID 7440-31-5 
Group in periodic table 14 
Group name None 
Period in periodic table
Block in periodic table p-block 
Color Silvery lustrous gray 
Classification Metallic 
Melting point 231.9 °C
Boiling point 2270 °C
Vaporization point 2602 °C
Thermal conductivity 66.8 W/(m·K) at 298.2 °K
Electrical resistivity 11.0 µΩ·cm at 0 °C; 15.5 µΩ·cm at 100 °C 
Electronegativity 1.7 
Specific heat 0.21 kJ/kg K
Heat of vaporization 290 kJ·mol-1
Heat of fusion 7 kJ·mol-1
Density of liquid 6.99 g/cm3 at 231.9 °C 
Density of solid 7.31 g/cm
Electron configuration [Kr]4d105s25p2 
Atomic radius 1.41 Å 
Oxidation states  +2, +4