How many valence electrons does oxygen have?

If you walked 8,000 meters today, how many kilometers (km) did you walk?

Below the structure for the myoglobin protein, an iron and oxygen-binding protein found in the muscle tissue of mammals.  What are the types of secondary structures that are present in this protein?  

The presence of several types of interactions between the side chains of a protein (electrostatic interactions, disulfide bonds, hydrogen bonding or hydrophobic interactions) is associated with which level of protein structure?

Which of the following compounds is classified as a thiol? Click on the correct compound.

What is the atomic number of an atom which is made up of 27 protons, 33 neutrons, and 27 electrons?  What is the identity of this atom?  

The sequence of amino acids is associated with which level of protein structure?

What is the mass number of an atom with 22 protons, 22 electrons, and 26 neutrons?

The octet rule refers to the tendency of certain elements to react in such a way that they achieve an outer shell of eight valence electrons.

Which of the following is the correct molecular formula for heptane?