The following chemical equation is not balanced: C3H8 + O2 CO2 + H2O When this chemical equation is correctly balanced, what is the coefficient of the carbon dioxide molecule?

The finches that Darwin studied in the Galapagos islands have evolved with different types of beaks: drilling, cracking, tearing, and fishing. This is an example of A) predation. B) adaptive radiation. C) warning coloration.

Which season will the northern hemisphere experience if the axis of Earth is tilted away from the sun? Fall Spring Summer Winter

Which formula represents an acid? A. CH4 B. HCl C. NH3 D. PH3

Why do Group 12 elements have different properties than Group 13 elements?

Identify each of the following as either a physical change or a chemical change. Explain your answers. A. a piece of wood is sawed in half. B. milk turns sour. C. melted butter solidifies in the refrigerator.

When you open a bottle of soda, bubbles of carbon dioxide start appearing. Is this a chemical or physical change and why?

Al2 (SO3) 3 what are the number of atoms

How marly electrons are in an atom of elemental sodium?

Petroleum and coal can be mined from the continental shelf. t/f

A solid substance turns into a liquid. Which best describes this change?