Actually, there are four kinds of reptile motion: 
Concertina - vermiform. Circular muscles around the snake squeeze the front of the snake's body out long, then the latter half is pulled forward. 
Rectilinear crawling - Belly scutes are moved forward individually in a wave-like motion. 
Side-winding - Snake's version of "walking". Use by several species to move over fluidic substrates, such as sand. 
Lateral undulation - Most common form of movement. Snake presses on alternating pressure points to force body forward (or backward)
(taken from a user on Yahoo from Correct Answers)
        
             
        
        
        
Answer:
Atoms form chemical bonds to make their outer electron shells more stable. ... An ionic bond, where one atom essentially donates an electron to another, forms when one atom becomes stable by losing its outer electrons and the other atoms become stable (usually by filling its valence shell) by gaining the electrons.
Explanation:
 
        
             
        
        
        
amount of product formed or amount of reactants used / time
 
        
             
        
        
        
High energy hope this helps