What can you determine about an element if you only know its group number

on the periodic table?

A. The number of valance electrons

B. The total number of protons and neutrons

C. The number of protons

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D. The total number of electrons

Which statement would indicate the presence of an acid? A) It tastes bitter ... B) It does not react with active metals. C) It reacts with active metals to form a gas. D) It does not change the color of litmus paper

Is carbon mixed with sand a mixture

All of the following are potential hazards in the environment except: A. lead B. asbestos C. pesticides D. lung cancer

What is the molar mass of Sr?

Why do electrons enter the 4s orbital before entering the 3d orbital? O A. because the 3d orbital is at a lower energy level OB. because both the 4s and 3d orbitals are at the same energy level O c.

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