Silicon Powder

CAS 7440-21-3
Linear Formula: Si
MDL Number: MFCD00085311
EC No.: 231-130-8

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(2N) 99% Silicon Powder
(3N) 99.9% Silicon Powder
(4N) 99.99% Silicon Powder
(5N) 99.999% Silicon Powder


Molecular Weight 28.08
Appearance Silvery
Melting Point 1414 °C
Boiling Point 2900 °C
Density 2330 kg/m3
Thermal Expansion

(25 °C) 2.6 µm·m-1·K-1

Poisson Ratio 0.064 - 0.28
Vickers Hardness N/A
Young's Modulus 51-80 GPa
Tensile Strength N/A
Thermal Conductivity 1.49 W/cm/K @ 298.2 K
Electronegativity 1.8 Paulings
Specific Heat 0.168 Cal/g/K @ 25 °C
Heat of Vaporization 40.6 K-Cal/gm atom at 2355 °C
Heat of Fusion 9.47 Cal/gm mole

Health & Safety Information

Signal Word Warning
Hazard Statements H228
Hazard Codes F
Precautionary Statements P210-P240-P241-P280-P370 + P378
Risk Codes 11
Safety Statements 16-33-36
RTECS Number VW0400000
Transport Information UN 1346 4.1/PG 3
WGK Germany 2

View and Print SDS


Date Accessed: 10/28/2016
Date Revised: 05/15/2015


Product Name: Silicon Powder

Product Number: All applicable American Elements product codes, e.g. SI-E-02-P , SI-E-03-P , SI-E-04-P , SI-E-05-P

CAS #: 7440-21-3

Relevant identified uses of the substance: Scientific research and development

Supplier details:
American Elements
1093 Broxton Ave. Suite 2000
Los Angeles, CA 90024
Tel: +1 310-208-0551
Fax: +1 310-208-0351

Emergency telephone number:
Domestic, North America +1 800-424-9300
International +1 703-527-3887


Classification of the substance or mixture
GHS Classification in accordance with 29 CFR 1910 (OSHA HCS)
Flammable solids (Category 2), H228
For the full text of the H-Statements mentioned in this Section, see Section 16.

Flame - GHS02

Signal word
Hazard statement(s)
Flammable solid.
Precautionary statement(s)
Keep away from heat/sparks/open flames/hot surfaces. - No smoking.
Ground/bond container and receiving equipment.
Use explosion-proof electrical/ ventilating/ lighting/ equipment.
Wear protective gloves/ protective clothing/ eye protection/ face protection.
P370 + P378
In case of fire: Use dry sand, dry chemical or alcohol-resistant foam for extinction.
Hazards not otherwise classified (HNOC) or not covered by GHS-none


Formula: Si
Molecular Weight: 28.09 g/mol
CAS-No.: 7440-21-3
EC-No.: 231-130-8


Description of first aid measures
General advice
Consult a physician. Show this safety data sheet to the doctor in attendance. Move out of dangerous area.
If inhaled
If breathed in, move person into fresh air. If not breathing, give artificial respiration. Consult a physician.
In case of skin contact
Wash off with soap and plenty of water. Consult a physician.
In case of eye contact
Rinse thoroughly with plenty of water for at least 15 minutes and consult a physician.
If swallowed
Do NOT induce vomiting. Never give anything by mouth to an unconscious person. Rinse mouth with water. Consult a physician.
Most important symptoms and effects, both acute and delayed
The most important known symptoms and effects are described in the labelling (see section 2) and/or in section 11.
Indication of any immediate medical attention and special treatment needed
no data available


Extinguishing media
Suitable extinguishing media
Use water spray, alcohol-resistant foam, dry chemical or carbon dioxide.
Special hazards arising from the substance or mixture
silicon oxides
Advice for firefighters
Wear self contained breathing apparatus for fire fighting if necessary.
Further information
Use water spray to cool unopened containers.


Personal precautions, protective equipment and emergency procedures
Use personal protective equipment. Avoid dust formation. Avoid breathing vapours, mist or gas. Ensure adequate ventilation. Remove all sources of ignition. Evacuate personnel to safe areas. Avoid breathing dust. For personal protection see section 8.
Environmental precautions
Prevent further leakage or spillage if safe to do so. Do not let product enter drains.
Methods and materials for containment and cleaning up
Sweep up and shovel. Contain spillage, and then collect with an electrically protected vacuum cleaner or by wet-brushing and place in container for disposal according to local regulations (see section 13). Keep in suitable, closed containers for disposal. Contain spillage, pick up with an electrically protected vacuum cleaner or by wet-brushing and transfer to a container for disposal according to local regulations (see section 13)
Reference to other sections
For disposal see section 13.


Precautions for safe handling
Avoid contact with skin andeyes. Avoid formation of dust and aerosols.Further processing of solid materials may result in the formation of combustible dusts. The potential for combustible dust formation should be taken into consideration before additional processing occurs.
Provide appropriate exhaust ventilation at places where dust is formed.Keep away from sources of ignition -No smoking.Take measures to prevent the build up of electrostatic charge.
For precautions see section 2.
Conditions for safe storage, including any incompatibilities
Keep container tightly closed in a dry and well-ventilated place.
Over time, pressure may increase causing containers to burst Moisture sensitive. Store under nitrogen. Keep in a dry place.
Specific end use(s)
Apart from the uses mentioned in section 1 no other specific uses are stipulated


Exposure controls
Appropriate engineering controls
Handle in accordance with good industrial hygiene and safety practice. Wash hands before breaks and at the end of workday.
Personal protective equipment
Eye/face protection
Safety glasses with side-shields conforming to EN166 Use equipment for eye protecti
on tested and approved under appropriate government standards such as NIOSH (US) or EN 166(EU).
Skin protection
Handle with gloves. Gloves must be inspected prior to use. Use proper glove removal technique (without touching glove's outer surface) to avoid skin contact with this product. Dispose of contaminated gloves after use in accordance with applicable laws and good laboratory practices. Wash and dry hands.
Body Protection
impervious clothing, Flame retardant antistatic protective clothing, The type of protective equipment must be selected according to the concentration and amount of the dangerous substance at the specific workplace.
Respiratory protection
Where risk assessment shows air-purifying respirators are appropriate use a full-face particle respirator type N100 (US) or type P3 (EN 143) respirator cartridges as a backup to engineering controls. If the respirator is the sole means of protection, use a full-face supplied air respirator. Use respirators and components tested and approved under appropriate government standards such as NIOSH (US) or CEN (EU).
Control of environmental exposure
Prevent further leakage or spillage if safe to do so. Do not let product enter drains.


Information on basic physical and chemical properties
Form: powder
Odour Threshold
no data available
no data available
Melting point/freezing point
Melting point/range: 1,410 °C (2,570 °F) - lit.
Initial boiling point and boiling range
2,355 °C (4,271 °F) - lit.
Flash point
no data available
Evapouration rate
no data available
Flammability (solid, gas)
The substance or mixture is a flammable solid with the category 2.
Upper/lower flammability or explosive limits
no data available
Vapour pressure
no data available
Vapour density
no data available
Relative density
2.33 g/mL at 25 °C (77 °F)
Water solubility
Partition coefficient: n-octanol/water
no data available
Auto-ignition temperature
> 400 °C (> 752 °F)
Decomposition temperature
no data available
no data available
Explosive properties
no data available
Oxidizing properties
no data available


no data available
Chemical stability
Stable under recommended storage conditions.
Possibility of hazardous reactions
no data available
Conditions to avoid
Heat, flames and sparks. Extremes of temperature and direct sunlight.
Incompatible materials
Strong oxidizing agents, Alkali carbonates, Calcium, cobalt difluoride, manganese trifluoride
Hazardous decomposition products
Other decomposition products - no data available
In the event of fire: see section 5


Information on toxicological effects
Acute toxicity
LD50 Oral - rat - 3,160 mg/kg
Inhalation: no data available
Dermal: no data available
no data available
Skin corrosion/irritation
no data available
Serious eye damage/eye irritation
Eyes - rabbit
Result: Mild eye irritation - 24 h
(Draize Test)
Respiratory or skin sensitisation
no data available
Germ cell mutagenicity
no data available
No component of this product present at levels greater than or equal to 0.1% is identified as probable, possible or confirmed human carcinogen by IARC.
No component of this product present at levels greater than or equal to 0.1% is identified as a carcinogen or potential carcinogen by ACGIH.
No component of this product present at levels greater than or equal to 0.1% is identified as a known or anticipated carcinogen by NTP.
No component of this product present at levels greater than or equal to 0.1% is identified as a carcinogen or potential carcinogen by OSHA.
Reproductive toxicity
no data available
no data available
Specific target organ toxicity - single exposure
no data available
Specific target organ toxicity - repeated exposure
no data available
Aspiration hazard
no data available
Additional Information
RTECS: VW0400000
To the best of our knowledge, the chemical, physical, and toxicological properties have not been thoroughly investigated.


no data available
Persistence and degradability
no data available
Bioaccumulative potential
no data available
Mobility in soil
no data available
Results of PBT and vPvB assessment
PBT/vPvB assessment not available as chemical safety assessment not required/not conducted
Other adverse effects
no data available


Waste treatment methods
Burn in a chemical incinerator equipped with an afterburner and scrubber but exert extra care in igniting as this material is highly flammable. Offer surplus and non-recyclable solutions to a licensed disposal company.
Contaminated packaging
Dispose of as unused product.


UN number: 1346
Class: 4.1
Packing group: III
Proper shipping name: Silicon powder, amorphous
Reportable Quantity (RQ):
Marine pollutant: No
Poison Inhalation Hazard: No
UN number: 1346
Class: 4.1
Packing group: III
EMS-No: F-A, S-G
Proper shipping name: SILICON POWDER, AMORPHOUS
Marine pollutant: No
UN number: 1346
Class: 4.1
Packing group: III
Proper shipping name: Silicon powder, amorphous


SARA 302 Components
SARA 302: No chemicals in this material are subject to the reporting requirements of SARA Title III, Section 302.
SARA 313 Components
SARA 313: This material does not contain any chemical components with known CAS numbers that exceed the threshold (De Minimis) reporting levels established by SARA Title III, Section 313.
SARA 311/312 Hazards
Fire Hazard
Massachusetts/Pennsylvania/New Jersey Right To Know Components
Revision Date
California Prop. 65 Components
This product does not contain any chemicals known to State of California to cause cancer, birth defects, or any other reproductive harm.


Safety Data Sheet according to Regulation (EC) No. 1907/2006 (REACH). The above information is believed to be correct but does not purport to be all inclusive and shall be used only as a guide. The information in this document is based on the present state of our knowledge and is applicable to the product with regard to appropriate safety precautions. It does not represent any guarantee of the properties of the product. American Elements shall not be held liable for any damage resulting from handling or from contact with the above product. See reverse side of invoice or packing slip for additional terms and conditions of sale. COPYRIGHT 1997-2016 AMERICAN ELEMENTS. LICENSED GRANTED TO MAKE UNLIMITED PAPER COPIES FOR INTERNAL USE ONLY.


Ultra High Purity Metal PowdersAmerican Elements specializes in producing high purity Silicon Powder with the smallest possible average grain sizes for use in preparation of pressed and bonded sputtering targets and in Chemical Vapor Deposition (CVD) and Physical Vapor Deposition (PVD) processes including Thermal and Electron Beam (E-Beam) Evaporation, Low Temperature Organic Evaporation, Atomic Layer Deposition (ALD), Metallic-Organic and Chemical Vapor Deposition (MOCVD). Powders are also useful in any application where high surface areas are desired such as water treatment and in fuel cell and solar applications. Nanoparticles also produce very high surface areas. Our standard powder particle sizes average in the range of - 325 mesh, - 100 mesh, 10-50 microns and submicron (< 1 micron). We can also provide many materials in the nanoscale range. We also produce Silicon as rod, ingot, pieces, pellets, disc, granules, wire, and in compound forms, such as oxide. Other shapes are available by request.



Chemical Identifiers

Linear Formula Si
CAS 7440-21-3
Pubchem CID 5461123
MDL Number MFCD00085311
EC No. 231-130-8
Beilstein Registry No. N/A
InchI Identifier InChI=1S/Si

Packaging Specifications

Typical bulk packaging includes palletized plastic 5 gallon/25 kg. pails, fiber and steel drums to 1 ton super sacks in full container (FCL) or truck load (T/L) quantities. Research and sample quantities and hygroscopic, oxidizing or other air sensitive materials may be packaged under argon or vacuum. Shipping documentation includes a Certificate of Analysis and Safety Data Sheet (SDS). Solutions are packaged in polypropylene, plastic or glass jars up to palletized 440 gallon liquid totes, and 36,000 lb. tanker trucks.

Related Products & Element Information

See more Silicon products. Silicon (atomic symbol: Si, atomic number: 14) is a Block P, Group 14, Period 3 element with an atomic weight of 28.085. Silicon Bohr MoleculeThe number of electrons in each of Silicon's shells is 2, 8, 4 and its electron configuration is [Ne] 3s2 3p2. The silicon atom has a radius of 111 pm and a Van der Waals radius of 210 pm. Silicon was discovered and first isolated by Jöns Jacob Berzelius in 1823. Silicon makes up 25.7% of the earth's crust, by weight, and is the second most abundant element, exceeded only by oxygen. The metalloid is rarely found in pure crystal form and is usually produced from the iron-silicon alloy ferrosilicon. Elemental SiliconSilica (or silicon dioxide), as sand, is a principal ingredient of glass, one of the most inexpensive of materials with excellent mechanical, optical, thermal, and electrical properties. Ultra high purity silicon can be doped with boron, gallium, phosphorus, or arsenic to produce silicon for use in transistors, solar cells, rectifiers, and other solid-state devices which are used extensively in the electronics industry.The name Silicon originates from the Latin word silex which means flint or hard stone.

Recent Research

Versatile Titanium Silicide Monolayers with Prominent Ferromagnetic, Catalytic, and Superconducting Properties: Theoretical Prediction., Wu, Qisheng, Zhang Jun-Jie, Hao Peipei, Ji Zhongyang, Dong Shuai, Ling Chongyi, Chen Qian, and Wang Jinlan , J Phys Chem Lett, 2016 Sep 9, p.3723-3729, (2016)

Testing the ability of plants to access potassium from framework silicate minerals., Manning, David A. C., Baptista Joana, Limon Mallely Sanchez, and Brandt Kirsten , Sci Total Environ, 2016 Sep 16, Volume 574, p.476-481, (2016)

A green and fast laser fusion technique for bulk silicate rock analysis by laser ablation ICP-MS., Zhang, Chenxi, Hu Zhaochu, Zhang Wen, Liu Yongsheng, Zong Keqing, Li Ming, Chen Haihong, and Hu Shenghong , Anal Chem, 2016 Sep 15, (2016)

Effects of pretreatments and hydrothermal aging on biaxial flexural strength of lithium di-silicate and Mg-PSZ ceramics., André, Maria, Kou Wen, Sjögren Göran, and Sundh Anders , J Dent, 2016 Sep 13, (2016)

Radiographic and Clinical Outcome of Silicate-substituted Calcium Phosphate (Si-CaP) Ceramic Bone Graft in Spinal Fusion Procedures., Alimi, Marjan, Navarro-Ramirez Rodrigo, Parikh Karishma, Njoku Innocent, Hofstetter Christoph P., Tsiouris Apostolos J., and Härtl Roger , Clin Spine Surg, 2016 Sep 10, (2016)

Ion-Doped Silicate Bioceramic Coating of Ti-Based Implant., Mohammadi, Hossein, and Sepantafar Mohammadmajid , Iran Biomed J, 2016 Sep, Volume 20, Issue 4, p.189-200, (2016)

Acid-resistant calcium silicate-based composite implants with high-strength as load-bearing bone graft substitutes and fracture fixation devices., Wei, Chung-Kai, and Ding Shinn-Jyh , J Mech Behav Biomed Mater, 2016 Sep, Volume 62, p.366-83, (2016)

Correlative micro-Raman/EPMA analysis of the hydraulic calcium silicate cement interface with dentin., Li, Xin, Pongprueksa Pong, Van Landuyt Kirsten, Chen Zhi, Pedano Mariano, Van Meerbeek Bart, and De Munck Jan , Clin Oral Investig, 2016 Sep, Volume 20, Issue 7, p.1663-73, (2016)

The influence of the electronic specific heat on swift heavy ion irradiation simulations of silicon., Khara, Galvin S., Murphy Samuel T., Daraszewicz Szymon L., and Duffy Dorothy M. , J Phys Condens Matter, 2016 Oct 5, Volume 28, Issue 39, p.395201, (2016)

Preparation of TiO2 nanotubes/mesoporous calcium silicate composites with controllable drug release., Xie, Chunling, Li Ping, Liu Yan, Luo Fei, and Xiao Xiufeng , Mater Sci Eng C Mater Biol Appl, 2016 Oct 1, Volume 67, p.433-9, (2016)

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