An 80.0 g sample of iodine-131 was placed in a sealed vessel forty days ago. only 2.5 g of this isotope is now left. what is its half-life?

Substance x has a fixed volume, and the attraction between its particles is strong .substance y had widely spread out particles and can be compressed what can most likely be concluded about these substances

You have a sample of a gas that occupies a volume of 17ml at -111 degrees celsius. what volume does the sample occupy at 88 degrees celsius? show all work asap

What is the atomic number of an atom that has 6 protons