How does the behavior of the water molecules change as the pan of water is heated?

In 2002, the rare earth elements mine in mountain pass, california was closed because

Word equation for k(s) +h2o(l) yield koh (aq) + h2

Large helium-filled balloons are used to lift scientific equipment to high altitudes. what is the pressure inside such a balloon if it starts out at sea level with a temperature of 10.0ºc and rises to an altitude where its volume is twenty times the original volume and its temperature is – 50.0ºc ?