A test tube of zinc oxide
        
                    
             
        
        
        
A COVALENT BOND, FORMS BETWEEN ELEMENTS WITH SIMILAR  ELECTRONEGATIVITY AS SHARING OF ELECTRON PAIRS BETWEEN ATOMS IS EASIER AS THEY ARE IDENTICAL. 
Explanation:
Bonding atoms with similar electronegativity values form covalent bonds.
A covalent bond, also called a molecular bond, is a chemical bond that involves the sharing of electron pairs between atoms. 
Covalent bonds form between two nonmetal atoms with identical or relatively close electronegativity values
Electronegativity is a measure of the tendency of an atom to attract a bonding pair of electrons, also it is the strength an atom has to attract a bonding pair of electrons to itself. 
Pure covalent bonds result when two atoms of the same electronegativity bond. This occurs only when two atoms of the same element bond with each other.
 
        
                    
             
        
        
        
Answer:
Chromosomes and I think its too many
Explanation:
 
        
             
        
        
        
Answer:
D.
The concentration of reactants and the concentration of products are constant.
Explanation:
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