The formation of covalent chemical bonds is

a. thermoneutral.

b. exothermic.

c. endothermic.

d. slow

What clues indicate that a rusty bike has gone through a chemical change

If an atom has 26 electrons, what is the least number of energy levels it has?

Why are ionic compounds brittle

Which statement about reaction rates is true? (A) Changing the temperature cannot speed up a reaction rate. (B) Changing the amount of reactants will not change the reaction rate. (C) Changing the surface area affects the reaction rate.

Cornea transplants are rarely rejected because the cornea has no blood supply explain why that is

Why reducing power of elements increase, on moving down a group?

Which of the following is not a result of air pollution? A. Smog B. Breathing problems C. Global warming D. Soil erosion

rank the following list of aqueous solutions and solvents according to decreasing vapor pressure the substance with the higher vapor pressure should be placed at top 0.10 M glucose pure water 0.050 M urea 0.20 M sucrose

What does the p mean in 1s22s22p63s1?

Why are alkaline earth metals and alkali metals found in nature by themselves?