# Phosphorous acid

Pyanodons fluid · internal name `phosphorous-acid` · first craftable in tier 2 (Logistic science pack, [tier 2](https://factorio.kalzumeus.com/tier/2.md))
HTML page: https://factorio.kalzumeus.com/fluid/phosphorous-acid/

## Produced by (2 recipes)

### Phosphorous acid (`phosphorous-acid`)

- 5 s · tier 2 · productivity modules allowed
- Ingredients: 80 × [Syngas](https://factorio.kalzumeus.com/fluid/syngas.md), 5 × [Powdered phosphate rock](https://factorio.kalzumeus.com/item/powdered-phosphate-rock.md), 20 × [Pure sand](https://factorio.kalzumeus.com/item/pure-sand.md), 4 × [Ash](https://factorio.kalzumeus.com/item/ash.md)
- Results: 50 × [Phosphorous acid](https://factorio.kalzumeus.com/fluid/phosphorous-acid.md)
- Made in: High pressure furnace MK 01, High pressure furnace MK 02, High pressure furnace MK 03, High pressure furnace MK 04
- Unlocked by: [Phosphorous processing](https://factorio.kalzumeus.com/tech/phosphorous-processing.md)

### Phosphorous acid (`purex-antimony-void`)

- 10 s · tier 4 · productivity modules allowed
- Ingredients: 60 × [Antimony phosphate 2](https://factorio.kalzumeus.com/fluid/sb-phosphate-2.md), 30 × [Purex concentrate 1](https://factorio.kalzumeus.com/fluid/purex-concentrate-1.md), 3 × [Plastic bar](https://factorio.kalzumeus.com/item/plastic-bar.md)
- Results: 120 × [Phosphorous acid](https://factorio.kalzumeus.com/fluid/phosphorous-acid.md), 0.5 × [Antimony oxide](https://factorio.kalzumeus.com/item/sb-oxide.md) (50% chance), 2 × [Plastic bar](https://factorio.kalzumeus.com/item/plastic-bar.md) (1–3)
- Made in: Scrubber MK 01, Scrubber MK 02, Scrubber MK 03, Scrubber MK 04
- Unlocked by: [Nuclear research](https://factorio.kalzumeus.com/tech/uranium-processing.md)

## Used in (4 recipes)

- Phosphorous acid distillation (`phosphoric-acid`, tier 2) → [Phosphine gas](https://factorio.kalzumeus.com/fluid/phosphine-gas.md)
- Z3 reagent (`z3-reagent`, tier 5) → [Z3 reagent](https://factorio.kalzumeus.com/fluid/z3-reagent.md)
- Ethyl mercaptan (`ethyl-mercaptan`, tier 7) → [Ethyl mercaptan](https://factorio.kalzumeus.com/fluid/ethyl-mercaptan.md)
- InGaP (`ingap`, tier 7) → [InGaP](https://factorio.kalzumeus.com/item/ingap.md)