Acrystalline material containing 30 grams of barium chloride crystals was placed into an oven at 400 degrees c and heated for two hours. it was then cooled and weighed. the new mass was less than before it was heated, containing 20 grams if barium chloride. how is this possible?

it is possible maybe the crystalline material containing 30 g of barium chloride is a hydrated barium chloride. So when it was heated, the water bounded was evaporated and the remaining barium chloride is only 20 g. I hope this can help.

window cleaner is ammonia dissolved in water. this is an example of a