How can you tell if a chemical reaction occurred?

A. Change in color

B. Created gas

C. Change in Temperature

D. Formed a precipitate

E. All of the above

Which is more reactive, Rubidium or Hydrogen?

A 100-g sample of zinc sulfide contains 67.1 g zinc and 32.9 g sulfur. If a 1.19-g sample of zinc is heated with excess sulfur, 1.77 g of zinc sulfide forms. Are these data in agreement with the law of definite proportions?

a student places a sample of white sodium bicarbonate powder in a test tube and heats it. The student observes that the sodium bicarbonate undergoes a chemical change. After the change, what must be true about the substance in the test tube?

DNA in water. Would you expect the double helix in a short segment of DNA to be more stable in 100 sodium phosphate buffer at pH 7.0 or in pure water? Why?

A pebble sinks in water a twig floats on top of the water compare the densities of the water the pebble and the twig

A hydrocarbon with only single bonds is classified as a. an alkene. b. an alkyne. c. saturated. d. unsaturated.

How many liters of 2M solution can be made using 500. grams of KI?

How many moles of copper are present in a sample of tennantite with a mass of 2370 grams

The Calvin cycle is another name for the

When a solution is considered to have a high concentration of hydrogen ions (H+) is also considered to be? a) acidic b) basic c) neutral d) hot