Fluorine has an atomic number of 9. Then n=1 energy level has two elections, and the n=2 energy level has seven electrons. Fluorine's valence is ___.

A) + 2

B) - 2

C) + 1

D) - 1

Which of the following statements is TRUE? a. Intact skin provides an impermeable barrier against all hazardous chemicals. b. It is safe to smoke around hazardous chemicals, as long as you wear gloves. c.

A good way for an adolescent to build and protect her bones is to:

Landfills produce methane, which is greenhouse gas and contributes to global warming true or false

In which TWO ways will a dog contribute to the carbon cycle? It will release carbon dioxide in the atmosphere through respiration. It will take in carbon dioxide from the atmosphere. Its feces will contain carbon that will enter the geosphere.

The endocrine system consist of glands that do what

Look at this definition: the inability to start a pregnancy after having unprotected vaginal intercourse for more than a year or the inability to stay pregnant for the full length of a normal pregnancy Which term does it define?

What relationship best applies between the pompeii worms and the bacteria?

What is the energy released during respiration used for?

How does the precision of measurements affect the precision of scientific calculations?

What are gametes??