Is silver tarnishing a chemical or physical change?

The cooling curve below represents the cooling of a sample of gas. According to the diagram, what phase (s) would you expect to observe when the substance is at 300 Kelvin?

Activation energy is only required to start an exothermic reaction. True or False?

What is the effect of an increase in the average kinetic energy of an object

Which is the atomic number of an atom that forms an ion with 18 electrons and a charge of 2+?

15.) Solar energy, wind, and geothermal are what type of energy resource? a.) Inexhaustible b.) Inexpensive c.) Nonrenewable d.) Chemical

Suppose the average concentration of copper in water is measured to be 2.5 x 10" M. a. Express this concentration in mg/L. b. Express this concentration in ug/L. c.

If I add water to oil what will happen

Commercial fertilizers, which are made by humans, are used to enrich soil for healthier crops. However, erosion may carry the fertilizer chemicals to the oceans. The presence of these chemicals may cause certain kinds of algae to reproduce rapidly.

A cube of iron has a temperature of 35°C. It is placed on top of a hot surface with a temperature of 175°C. What will happen to the iron? A) Its temperature will decrease. B) Heat will flow from the hot surface into the iron.

Density differences cause the