Which of the following is the best indication that a chemical change has taken place?

a. The matter changes color.

b. A mixture separates into layers.

c. The change is reversible.

d. The shape of the substance changes.

Which of the following apply to diffusion. Select all that apply. Solids can diffuse in liquids. Liquids can diffuse in liquids. It is the process of intermingling atoms from one substance into another.

Fish that feed on sediment will most likely be found in rivers

A fish in the sea in the deep ocean has a lure that lights up to attract mates and prey. Why would it need this in adaptation

If a log is burning and the amount of oxygen reaching he log is decreased what happens

One type of electromagnetic radiation that could harm humans

A radioactive sample is 555 years old. It's half life is 111 years. How many half lives?

An ion of magnesium has 12 protons and a charge of + 2. how many electrons are in this ion? A. 2 B. 20 C. 12 D. 14

A mixture consists of sand and an aqueous salt solution. Which procedure can be used to separate the sand, salt, and water from each other? (1) Evaporate the water, then filter out the salt. (2) Evaporate the water, then filter out the sand.

Identify the components of a fuel cell. zinc-manganese hydrogen-oxygen nickel-metal hydride lithium ion nickel-cadmium

For the reaction hconh2 (g) ânh3 (g) + co (g), k = 4.84 at 400 k what can be said about this reaction at this temperature?