What are valence electrons? A. the atomic mass

B. the atomic number

C. all of the electrons in an atom

D. electrons in the outermost energy level

D

Explanation:

The simple answer is the electrons in the outermost energy level.

Hydrogen has 1 electron in the outermost energy level.

Magnesium has 2 so this tells you that magnesium has a charge of 2

Oxygen has 6  oxygen has a charge of - 2

Fluorine has 7

For most elements, the electrons in the most outer ring determine the valence of the element.

Notice that the non metals work differently than the metals. Mg may have a charge of 2 and that is the number of electrons in the valence right.

Oxygen is a non metal it has a charge of - 2. It gets 6 electrons by subtracting the number of its charge from 8.

D. electrons in the outermost energy level

Explanation:

The valence electrons are the electrons in the outermost energy level.

"1. it should be, it has been for about 20 years, and it's really not much different in the end than breeding animals to have particular traits. there are always concerns about genetically engineered animals/plants affecting the environment in unexpected negative ways, but i can't think of an example where the fears didn't turn out to be baseless.  

first, as you point out, it would be a great advance in pharmacology, to be able to tailor drugs and their doses to me. the pros involve better medical treatment. the cons involve privacy issues like insurance companies denying coverage to people with genetic risk factors. looking at dna markers wouldn't affect the frequency of genetic diseases, but it would allow detection of them earlier. and ok, actually i suppose that if people used this information to avoid having children with genetic diseases, some might decrease in frequency."

the answer is lactic acid from anaerobic respiration. the acid in lactic acid is what creates sore and burning muscles. if you think about how acid burns that will give you a clue for questions like this.