Answer:
A
Explanation:
Quaternary structure of proteins is composed of two or more polypeptide chains. Insulin has two; one alpha and one beta chain. The two chains are joined together by disulfide bonds at two points (at cysteines). Other examples of quaternary proteins structures are DNA polymerase and hemoglobin.
<span>A covalent bond is a bond formed by atom sharing.
In water molecule, there are twice the number of hydrogen atoms than the oxygen atoms. Its structure is H-O-H. The electronegative difference between the H and O allows them to be polar because on side there is positive charge and on another side there is negative charge.</span>
Balanced equation: 2Fe + 3H2O → Fe2O3 +3H2
Convert g to mols:
285/55.845 = 5.1034 mols
Mole ratio of Iron and Iron (III) Oxide: 2:1
5.1034/2 = 2.5517 mols
The answer is "c" because solidification or freezing is the term used for the process in which a liquid becomes a solid.<span> Freezing is an exothermic process that also is an example of a phase transition</span>
