Sodium acetate

Sodium acetate ;
Names:	sodium acetate; sodium ethanoate; Е262 food additive;
Formula:	NaCH3COO (anhydrous); NaCH3COO · 3H2O (trihydrate);
Molar mass:	82.034 g/mol (anhydrous); 136.078 g/mol (trihydrate);
Density:	1.528 g/cm3 (anhydrous); 1.45 g/cm3 (trihydrate);
Crystal system:	monoclinic (trihydrate); a=12.475 Å, b=10.407 Å, c=10.449 Åα=90°, β=112.65°, γ=90°;
Shapes:	https://en.crystalls.info/w/uploads/media/3/36/Oblique_rhombic_prism.json Oblique rhombic prism https://en.crystalls.info/w/uploads/media/1/12/Trapezoidal_flat_prism.json Trapezoidal flat prism https://en.crystalls.info/w/uploads/media/5/52/Needle.json Needle ;
Color:	colorless;
Melting point:	58 °C331.15 K <br />136.4 °F <br />596.07 °R <br /> (trihydrate); 328.2 °C601.35 K <br />622.76 °F <br />1,082.43 °R <br /> (anhydrous);
Refractive index:	1.455 (trihydrate);
Magnetic properties:	diamagnetic; χ=-3.76 · 10-5cm³/mol;
Stability:	erodes during 15 minutes (trihydrate);
Hardness:	fragile;
Toxicity:	non-toxic; LD50=3530mg/kg

Description

Organic compound, salt of alkaline metal sodium and organic acetic acid. From water solutions crystallizes as trihydrate.

Where to buy

Can be bought in pharmacy (as "heating pad").

Add acid to the flask, then add small parts of sodium compound with stirring until heating will stop (attention, the solution may boil!) or, if you use carbonate, until carbon dioxide emission will stop. After reaction will stop, filter the solution and use it for crystal growing.

Reaction between sodium sulfate and calcium or lead(II) acetate

You can use sodium chloride instead of sulfate if you use lead salt.
Chemical equation:

Ca(CH₃COO)₂ + Na₂SO₄ = 2NaCH₃COO + CaSO₄↓

Pb(CH₃COO)₂ + Na₂SO₄ = 2NaCH₃COO + PbSO₄↓

Pb(CH₃COO)₂ + 2NaCl = 2NaCH₃COO + PbCl₂↓

For preparation of 100.00g of sodium acetate

trihydratetrihydrate
anhydrous

а 118.38g of sodium sulfate

decahydratedecahydrate
anhydrous

or 42.95g of sodium chloride and 64.73g of calcium acetate

monohydratemonohydrate
anhydrous

or 139.38g of lead(II) acetate

trihydratetrihydrate
anhydrous

is required.

Add to the flask with calcium or lead acetate solution small parts of sodium salt solution and stir. The large amount of poorly soluble precipitate will form. Settle it out and discard, then filter the solution carefully.

Influence of temperature

Compound is able to form a supersaturated solution or melt which doesn`t crystallize spontaneously itself and can remain in this state for long time. But an external action like touch or dust triggers a nuclear crystallization with releasing large amount of heat. This process used in heating pads and experiment called "Hot ice".
Cooling speed has much impact on end crystal form. For example, if cooling was too fast, the threads are formed, if cooling was slow, the needles are formed, and when temperature is constantly room temperature, the prismatic crystals are formed.

Storage conditions

For crystal storing use hermetic vessel with wadding moistened with such solution near the crystal. You can use such alternatives as vessel with vaseline or vegetable oil, organic non-hygroscopic solvent (kerosene or liquid paraffin). Also you can use acrylate polymer or another kinds of solidifying plastic.

Solubility

TableGraph

Temperature	g/`100,00` g water		g/`100,00` g ethanol		g/`100,00` g methanol	g/`100,00` g acetone	g/`100,00` g ethylene glycol	g/`100,00` g formic acid	g/`100,00` g acetic acid	g/`100,00` g hydrazine	g/`100,00` g dimethylformamide
Temperature	(anhydrous)	(trihydrate)	(anhydrous)	(trihydrate)	(anhydrous)	(trihydrate)	(trihydrate)	(trihydrate)	(trihydrate)	(trihydrate)	(trihydrate)
0°C273.15 K <br />32 °F <br />491.67 °R <br />	`119`	`79`						`7.76`
10°C283.15 K <br />50 °F <br />509.67 °R <br />	`121`	`~124`		`2.08`
15°C288.15 K <br />59 °F <br />518.67 °R <br />					`16`	`0.05`
20°C293.15 K <br />68 °F <br />527.67 °R <br />				`2.33`						`6`
25°C298.15 K <br />77 °F <br />536.67 °R <br />			`5.3`	`7.8`			`29.03`		`10.46`		`1.5`
30°C303.15 K <br />86 °F <br />545.67 °R <br />	`126`
50°C323.15 K <br />122 °F <br />581.67 °R <br />	`134`	`304`
70°C343.15 K <br />158 °F <br />617.67 °R <br />	`146`				`16.55`
80°C353.15 K <br />176 °F <br />635.67 °R <br />	`153`
90°C363.15 K <br />194 °F <br />653.67 °R <br />	`161`
100°C373.15 K <br />212 °F <br />671.67 °R <br />	`170`								`67.79`

Slightly soluble in diethyl ether.

Gallery

Slow solution evaporate at room temperatureSodium acetate, Aleksandr Korchemkin, VKontakteAleksandr KorchemkinVKontakte
Slow solution evaporate at room temperatureSodium acetate, Aleksandr Korchemkin, VKontakteAleksandr KorchemkinVKontakte
Fast solution coolingSodium acetate, Yaroslav Zavada, VKontakteYaroslav ZavadaVKontakte
Fast solution coolingSodium acetate, Yaroslav Zavada, VKontakteYaroslav ZavadaVKontakte
Growing at surface of copper(II) acetateSodium acetate, Yaroslav Zavada, VKontakteYaroslav ZavadaVKontakte
Growing at surface of copper(II) acetateSodium acetate, Yaroslav Zavada, VKontakteYaroslav ZavadaVKontakte
Sodium acetateToffel, WikimediaToffelWikimedia

Video

Sources

Acetates

Salts

Calcium acetate (Ca(CH₃COO)₂) • Copper(II) acetate (Cu(CH₃COO)₂) • Chromium(II) acetate (Cr(CH₃COO)₂) • Gadolinium acetate (Gd(CH₃COO)₃) • Dysprosium acetate (Dy(CH₃COO)₃) • Holmium acetate (Ho(CH₃COO)₃) • Iron(II) acetate (Fe(CH₃COO)₂) • Lead(II) acetate (Pb(CH₃COO)₂) • Manganese(II) acetate (Mn(CH₃COO)₂) • Neodymium acetate (Nd(CH₃COO)₃) • Nickel acetate (Ni(CH₃COO)₂) • Samarium acetate (Sm(CH₃COO)₃) • Strontium acetate (Sr(CH₃COO)₂) • Sodium acetate (NaCH₃COO) • Zinc acetate (Zn(CH₃COO)₂)

Double Salts

Copper-calcium acetate (CuCa(CH₃COO)₄) • Uranyl-sodium acetate (NaUО2(CH₃COO)₃) • Uranyl-zinc-sodium acetate (NaZn(UO₂)₃(CH₃COO)₉)

Sodium compounds
Salts	Sodium acetate (NaCH₃COO) • Sodium bromide (NaBr) • Sodium citrate (Na₃C₃H₅O(COO)₃) • Sodium chlorate (NaClO₃) • Sodium chloride (NaCl) • Sodium cyclamate (C₆H₁₂NNaO₃S) • Sodium decavanadate (Na₆V₁₀O₂₈) • Sodium ethilate (NaC₂H₅O) • Sodium glutamate (NaC₅H₈NO₄) • Sodium hydrocarbonate (NaHCO₃) • Sodium hydrosulfate (NaHSO₄) • Sodium iodide (NaI) • Sodium metavanadate (NaVO₃) • Sodium niobate (NaNbO₃) • Sodium nitrate (NaNO₃) • Sodium oxalate (Na₂C₂O₄) • Sodium para-aminosalicylate (C₇H₆NNaO₃) • Sodium perchlorate (NaClO₄) • Sodium saccharinate (C₇H₄NaNO₃S) • Sodium sulfate (Na₂SO₄) • Sodium sulfide (Na₂S) • Sodium tetraborate (Na₂B₄O₇) • Sodium thiosulfate (Na₂S₂O₃) • Sodium trichloroacetate (NaCCl₃COO) • Sodium trioxalatoaluminate (Na₃[Al(C₂O₄)₃]) • Sodium tungstate (Na₂WO₄)
Double salts	Potassium-sodium tartrate (KNaC₄H₄O₆) • Sodium-ammonium sulfate (NaNH₄SO₄) • Uranyl-sodium acetate (NaUО2(CH₃COO)₃) • Uranyl-zinc-sodium acetate (NaZn(UO₂)₃(CH₃COO)₉) • Zinc-sodium sulfate (Na₂Zn(SO₄)₂)
Adducts	Glucose and sodium bromide adduct (2C₆H₁₂O₆ · NaBr) • Glucose and sodium chloride adduct (2C₆H₁₂O₆ · NaCl) • Urea and sodium chloride adduct (CO(NH₄)₂ · NaCl)
Complex compounds	Sodium dicarbonatocuprate(II) (Na₂[Cu(CO₃)₂]) • Sodium dioxalatocuprate(II) (Na₂[Cu(C₂O₄)₂]) • Sodium ethylenediaminetetraacetate-ferrate(III) (Na[Fe((OOCCH₂)₂N(CH₂)₂N(CH₂COO)₂)]) • Sodium hexacyanoferrate(II) (Na₄[Fe(CN)₆]) • Tripotassium-sodium hexacyanoferrate(II) (K₃Na[Fe(CN)₆]) • Sodium hexafluorosilicate (Na₂[SiF₆]) • Sodium nitroprusside (Na₂[Fe(CN)₅NO]) • Sodium trioxalatochromate(III) (Ns₃[Cr(C₂O₄)₃]) • Dipotassium-sodium trioxalatoferrate(III) (K₂Na[Fe(C₂O₄)₃]) • Potassium-sodium trioxalatoferrate(III) (K₅Na[Fe(C₂O₄)₃]₂) • Sodium trioxalatoferrate(III) (Na₃[Fe(C₂O₄)₃])

Sodium acetate
Names:	sodium acetate sodium ethanoate Е262 food additive
Formula:	NaCH₃COO (anhydrous) NaCH₃COO · 3H₂O (trihydrate)
Molar mass:	82.034 g/mol (anhydrous) 136.078 g/mol (trihydrate)
Density:	1.528 g/cm³ (anhydrous) 1.45 g/cm³ (trihydrate)
Crystal system:	monoclinic (trihydrate) a=12.475 Å, b=10.407 Å, c=10.449 Åα=90°, β=112.65°, γ=90°
Shapes:	Oblique rhombic prism Trapezoidal flat prism Needle
Color:	colorless
Melting point:	58 °C331.15 K <br />136.4 °F <br />596.07 °R <br /> (trihydrate) 328.2 °C601.35 K <br />622.76 °F <br />1,082.43 °R <br /> (anhydrous)
Refractive index:	1.455 (trihydrate)
Magnetic properties:	diamagnetic χ=-3.76 · 10^-5cm³/mol
Stability:	erodes during 15 minutes (trihydrate)
Hardness:	fragile
Toxicity:	non-toxic LD₅₀=3530mg/kg