Which is not a physical property of water? a. water is colorless. b. the freezing point of water is 0 ºc. c. water reacts with sodium metal to produce sodium hydroxide and hydrogen. d. the density of water at 4 ºc is 1.00 g/ml?

How is 0.00235 expressed in proper scientific notation? a. 2.35 × 10-3 b. 0.235 × 10-2 c. 2.35 d. 2.35 × 103

Joan writes four numbers on the board in standard form, and then she writes their scientific notation

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.