How many grams of water could be made from 5.0 mol H2 with excess O2? 2 H2 + O2 --> 2 H2O

According to each substances heat of fusion, which of the items below requires more heat to be added per gram of substance to go from solid to liquid? silver sulfur water lead

2pos suppose an object in free fall is dropped from a building. its starting velocity is 0 m/s. ignoring the effects of air resistance, what is the speed (in m/s) of the object after falling 3 seconds? give your answer as a positive decimal without units. answer here

How have the greenhouse gasses increased from the year 2000 to 2018