Sodium Dithionite is the same as Sodium hydrosulfite CAS N°: 7775-14-6. Formula Na₂S₂O₄

This is a strong reducing agent for indigo vats.

The difference for this powder is that it does not have the strong sulfur smell that comes with traditional sodium hydrosulfit.

For use in an indigo vat I usually use the formula of 5 grams indigo, 5 grams of sodium diothonite and 12 grams of soda ash per liter water. You multiply this per the number of liters you want your vat to be.

This powder is packed in a 250 gram in a double plastic ziplock bag.

Key Spec Table

CAS #	EC Number	Hill Formula	Chemical Formula	Molar Mass
7775-14-6	231-890-0	Na₂O₄S₂	Na₂S₂O₄	174.11 g/mol

Description
Catalogue Number	106505
Synonyms	Sodium hydrosulfite, Sodium hypodisulfite

Product Information
CAS number	7775-14-6
EC index number	016-028-00-1
EC number	231-890-0
Hill Formula	Na₂O₄S₂
Chemical formula	Na₂S₂O₄
Molar Mass	174.11 g/mol
HS Code	2831 10 00
Quality Level	MQ200

Physicochemical Information
Density	2.5 g/cm3 (20 °C)
Flash point	>100 °C
Ignition temperature	>200 °C
Melting Point	100 °C (decomposition)
pH value	5.5 - 8.5 (50 g/l, H₂O, 20 °C)
Bulk density	1250 kg/m3
Solubility	250 g/l (slow decomposition)