The reactivity of an atom arises from

a. The number of electrons in the nucleus.

b. The number of protons in the nucleus.

c. The number of electrons in the valence shell.

d. The atomic mass.

A compound has 39 g of potassium and 78 g of selenium. What is the mass ratio of potassium and selenium in the compound

How much more basic is a solution with pH 10 than a solution with pH 8? A. 2 times B. 6 times C. 10 times D. 100 times

Pure water is neutral. What is the appropriate justification for this? Water has equal H + and OH - ions, making its pH 7, which is considered a neutral pH. Water has more H + than OH - ions, making its pH 5, which is considered a neutral pH.

What do the digestive and excretory systems have in common? Both break down food. Both produce urine. Both get rid of waste material. Both filter out waste material.

Which of the following best defines conduction? A. the movement of energy by waves that travel through space B. the movement of a hot liquid of gas from one place to another, carrying energy with it C.

Which two body systems contribute to acid-base balance of blood?

In which phase of matter do the molecules that make up the substance have the greatest kinetic energy

The atoms of the elements in this group are the most chemically reactive of the ones listed.

What is the name of NiI2

Give an example of how microorganisms might meet each of the challenges of life