Acopper sheet is heated in a furnace until it melts. the hot liquid copper is then cooled until it becomes solid again. compare the mass of the copper before and after melting. a) the new solid copper is lighter than the original sheet. eliminate b) the new solid copper is heavier than the original sheet. c) the new solid copper is the same weight as the original sheet. d) the molten copper was lighter than the sheet or the new solid.

What is the mass of each element in a 324.8 sample of co2

Calculate the molarity of each of the following solutions. part a) 0.12 mol of lino3 in 5.5 l of solution part b) 60.7 g c2h6o in 2.48 l of solution part c) 14.2 mg ki in 100 ml of solution

Nebulae are enormous clouds in outer space. they are made mostly of hydrogen gas, helium gas, and dust. some nebulae glow brightly, while others do not. the stars that people see are huge, bright balls of glowing gas. they are made mostly of hydrogen and helium. which statement correctly describes other ways in which nebulae and stars are different? a. stars can form inside a nebula but a nebula can never be produced by any star. b. a star always has a higher density than a nebula. c. stars can never form inside a nebula but a nebula can be produced by any star. d. a nebula always has a higher density than a star.