Louis was investigating physical and chemical changes in matter. Which of these changes that Louis found involves a chemical change in matter? Melting of ice
Grinding of rock
Evaporation of water
Rusting of iron

Jessica is traveling from miami, florida, to chicago, illinois. using the map, tell one way the land will change during the second half of her trip.

Why does the sun appear to be the brightest star in the sky? a- its apparent brightness is much greater than other stars. b- it burns more gas, making it brighter than any other star. c- it is the largest star in the galaxy, so it is the brightest star. d- its relative distance to earth is closer than the other stars.

Which statement is usually true about the relationship between activation energy and reaction rates? low activation energy barriers result in low rates. high activation energy barriers result in low rates. low activation energy barriers result in no reaction. high activation energy barriers result in no reaction.