Classify each item as a pure substance or a mixture: (a) blood; (b) ocean water; (c) a piece of wood; (d) a chunk of ice.

A glass of water contains 1.2 x 1024 molecules of water. An additional 5.0 moles of water are poured into the glass. How many molecules of water are in the glass?

The half-life of strontium-90 is 28 years. how long will it take a 52 mg sample to decay to a mass of 13 mg?

What can be said about the level of carbon-14 in living organisms? A. It stays the same. B. It decreases. C. It increases.

Why is cloth not used to make furniture? A. Cloth is not hard and would collapse under a person's weight. B. Cloth is transparent and would not cover the floor. C. Cloth melts under heat and would change shape in the summer. D.

Why does black asphalt road become hotter than a white cement sidewalk in the same amount of sunlight?

What variables affect the acceleration of an object and in what manner do they affect the acceleration?

How do valence electrons relate to the chemical reactions of an element?

What is the weighted-average mass of all known isotopes for an element

What is the Celsius equivalent of 212°f

Identify the characteristics of tornadoes and hurricanes