What are valence electrons? How would you determine the valence electrons of Oxygen?

Valence electrons are the electrons located on the outer shell of the atom. To determine valence electrons of oxygen you can count how many electrons ae on the last shell of it's bohr diagram.

Explanation:

the ozone layer acts as a filter for the shorter wavelength and highly hazardous ultraviolet radiation (uvr) from the sun, protecting life on earth from its potentially harmful effects. when the sky is clear, there is an inverse relationship between stratospheric ozone and solar uvr measured at the earth's surface.

the major pests we deal with are insects, weeds and fungal diseases. a pesticide is a product, whether organic or chemical, used to kill the target pest. there are other techniques gardeners should use that can prevent the severe infestations that make the use of pesticides necessary