How many moles of hydrogen atoms are present in 25.0 g of water?

What is impossible to do with a hypothesis

One does not belong why? ice, gold ,wood ,diamond and table salt

Three cards with holes are arranged in a straight line. a light is shined through the first card’s hole and travels through all three cards. what does this tell you about light rays? a) that light is reflected b) that light is refractive c) that light travels in a straight line d) that light does not travel in a straight line