Note: pm is ”picometer” or 1 x 10-12 m.

calculate the answer in units of g/cm3.

calculate the average density of a single

atom by assuming that it is a uniform sphere

of radius 135.9 pm and its mass is 5.71 ×

10^−22 g. the volume of a sphere is 4

3

π r3

.

answer in units of g/cm3

.

The characteristics of two different types of reactions are shown below: reaction a: electrons are gained by the atoms of an element. reaction b: protons are lost by the atom of an element. which statement is true about the atoms of the elements that participate in the two reactions? their identity changes in both reaction a and reaction b. their identity changes in reaction a but not in reaction b. their identity changes in reaction b but not in reaction a. their identity remains the same in both reaction a and reaction b.

Write a balanced equation showing the formation of copper (ii) nitrite from its elements

In chemistry, the type of an atom (what element it is) is determined by: a) the number of protons it contains in its nucleus. b) the number of neutrons it contains in its nucleus. c) the number of protons it has in a cloud around the nucleus. d) the number of neutrons it has in a cloud around the nucleus. e) the number of electrons it exchanges with its neighbors.