210Bi (an isotope of bismuth) has a half-life of 5.0 days. The time for seven-eighths of a sample of 210Bi to decay is

How has the scientific community addressed the safety of chemicals? a. chemicals are repeatedly tested, even those that have existed for a long time. b. existing chemicals are tested if they have never been tested before. c. chemicals are tested if they are suspected to have caused a problem. d. only new chemicals are tested.

The difference between the atomic number of an element and the element’s atomic mass is the number of ions.

You are making a solution of calcium chloride dissolved in water. you add solid, stir, and it dissolves. you add just a spatula tip full, stir, and the solid does not dissolve. how could you describe the solutions before and after adding the spatula tip amount