Potassium chromate. Preparation kwemakemikari uye mumuviri zvivako. kunyoresa

potassium chromate kana potassium hromovoloknisty (zita renyika: Kalium chromicum, Kaliumchromat, Potassium chromate) - iri inorganic remubatanidzwa, yellow crystals ari orthorhombic ezvinhu, soluble mumvura. Rinoreva munyu pamusoro chromic asidhi H2CrO4, izvo vakasununguka mamiriro haako. In fuma potassium chromate mutoo: CrK2O4

How kuti potassium chromate?

Hromovoloknisty potassium vakawana nenzira dzakawanda:

1. By chromium oxide oxidation potassium chlorate (maitiro kunoitika panguva imwe tembiricha kuti 500-700 madhigirii):

Cr2O3 (chromium oxide) + KClO3 (potassium chlorate) + K2CO3 (potassium carbonate) = 2K2CrO4 (potassium chromate) + KCl (potassium chloride) + 2CO2 (carbonic asidhi gasi)

2. By Kuparadzwa ari chromium oxide iri potassium hydroxide :

CrO3 (chromium oxide) + 2KOH (potassium hydroxide) = K2CrO4 (potassium chromate) + H2O (mvura)

3. By manyowa kuti potassium dichromate nokuda kudziyisa (maitiro rinoitwa panguva tembiricha kuti 500-600 madhigirii):

4K2Cr2O7 (potassium dichromate) = 4K2CrO4 (potassium chromate) + 2Cr2O3 (chromium oxide) + 3O2 (okisijeni)

4. By kugara kuti kuramba mhinduro kuti potassium hydroxide kuti potassium dichromate :

K2Cr2O7 (potassium dichromate) + 2KOH (potassium hydroxide) = 2K2CrO4 (potassium chromate) + H2O (mvura)

5. The zvakaita chisingawanzowaniki chicherwa kuti unonzi 'tarapakait ". It hromovoloknisty potassium chiwanikwa.

Potassium chromate mushonga ehupfumi:

1. sanganisa acids hromovoloknisty potassium anopinda potassium dichromate, vane mutoo K2Cr2O7. Muenzaniso zvinotevera maitiro:

2K2CrO4 (potassium chromate) + 2HCl (hydrochloric asidhi rakasanganiswa) = K2Cr2O7 (potassium dichromate) + 2KCl (potassium chloride) + H2O (mvura)

2. Kana tikafunga simba acids vane zvakasiyana ichaitika, somuenzaniso:

K2CrO4 (potassium chromate) + 2HCl (hydrochloric asidhi mu pfungwa yokushanda chimiro) K = (Kr (Cl) O3) (complexed chromium) + KCl (potassium chloride) + H2O (mvura)

3. Zvakaitwa pamwe potassium chromate inopisa dzichiitika acids zviratidzwa oxidizing ehupfumi. Muenzaniso ari zvinotevera zvakaitwa rinoitwa panguva tembiricha rworwendo 90:

2K2CrO4 (potassium chromate) + 16HCl (hydrochloric acid) = 2CrCl3 (chromium chloride) + 3Cl2 (sezvo kuiisa chlorine gasi) + 4KCl (potassium chloride) + 8H2O (mvura)

4. Hromovoloknisty potassium tindopinda chinjanai zvavaifunga. Somuenzaniso:

K2CrO4 (potassium chromate) + 2AgNO3 (sirivha nitrate) = Ag2CrO4 (sirivha chromate, precipitates) + 2KNO3 (potassium nitrate)
K2CrO4 (potassium chromate) + Hg2 (NO3) 2 (nemekiyuri nitrate) = Hg2CrO4 (nemekiyuri chromate precipitates) + 2KNO3 (potassium nitrate)

The ehupfumi zvokunyama kuti potassium chromate:

1. arambe achirema iri 2,732 g / cm3.
2. Potassium chromate inonyunguduka pa 968,3 ° C. Pamusangano tembiricha kuti 668 madhigirii anopinda tsvuku hexagonal kutotanga - anowana mumwe ruvara - red. Zvisinei, pamusoro kutonhora vakava tsvuku zvakare.
3. Forms yero crystals rhombic hurongwa.
4. Nderake pazvakaringana boka P-Nam.
5. rinoreva paramagnetic.
6. soluble Varombo panyaya iyi, insoluble mumvura. Soluble mu ethyl doro uye diethyl.
7. matadza gobvu ndiro 194,19 g / mol.

Optical ehupfumi kuti potassium chromate:

The refractive Indekisi 1,74

Where zvinoshanda potassium chromate?

1. redehwe indasitiri rinoshandiswa senzira kusukuta matehwe mumiririri. In värjäys kuti micheka senzira mordant.
2. Rinoshandiswa sezvo varimowo muboka revaya electrolyte Zvinoumba rinokosha namakemikari degreasing.
3. Sezvo brightener kuti wakisi uye mafuta.
4. Organic kwetunhu sechinhu oxidant Somuenzaniso, muna pagadzirwe madhayi.
5. Uyewo hromovoloknisty potassium mhinduro rakashandiswa kugadzirira electrochemical oxidation yesirivha, uye nokuda kwemutemo zvigadzirwa kubva mhangura uye sirivha alloys.
6. akashandiswa senzira Homeopathic mushonga mune zvokurapa.
7. mumarabhoritari washing musanganiswa zvakaenzana zvemaBhaibheri kuramba sulfuric asidhi uye K2Cr2O7 mhinduro, kare zvakazara muchando.

Potassium dichromate (the hwokugadzira zita - Chrompick)

Rinomirira crystals Red-Orange ruvara. No crystalline siyana, ane arambe achirema pamusoro 2,684 giremu pa cubic sendimita, inonyunguduka pa 397 inegumi. zvimwe On kudziyisa uchiora. Solubility mumvura pa 20 madhigirii akaenzana 12,48 magiramu munyu chete 100 magiramu mvura. Potassium dichromate rinoshandiswa nevakawanda sechinhu oxidant ari pyrotechnics, mutambo indasitiri, uye somunhu reagent mu hromametrii.