求翻译：溶于水并缓慢分解放出氢气是什么意思？

Soluble in water and slowly break down to release hydrogen

Soluble in water and the liberation of hydrogen gas slowly

Dissolves emits the hydrogen in the water and the slow decomposition

Soluble in water and slowly decompose to release hydrogen gas

Appearance: colourless crystals or white powder. Hygroscopicity. Density of 2.33. At 180 ° c losing two molecular crystal water, 300 c lose all their water of crystallization. Nature and sodium pyrophosphate similar, but larger solubility. Soluble in water, insoluble in ethanol