In the following reaction: 4 Al + 3 O2 –> 2 Al2O3 How many moles of aluminum would be needed to completely react with 90 grams of O2?

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.

What methods could you use to solubilize calcium carbonate

In general metals get as you move from left to right across the periodic table.