iron sulfate

例句：

1. 1. The iron sulfate crystals are very hard and can be used as a building material.
   硫酸铁晶体非常坚硬，可以用作建筑材料。
2. 2.The iron sulfate solution is used to remove rust from metal surfaces.
   硫酸铁溶液用于从金属表面去除锈迹。
3. 3.The iron sulfate was found in the river sediments, indicating that the water had been contaminated with industrial waste.
   在河流沉积物中发现硫酸铁，表明河水已被工业废物污染。