Points 8 Submitting a text entry box ue Jun 15 by 11:59pm h.5 Review. Use your t
ID: 297239 • Letter: P
Question
Points 8 Submitting a text entry box ue Jun 15 by 11:59pm h.5 Review. Use your textbook and module content to answer the following uestions. . Describe the polarity and the structure of water molecules. What are hydrogen bonds? 2. Define salinity. 3. What are the dissolved components in seawater (use table 5.1)? 4. What processes decrease salinity? 5. What processes increase salinty? 6. Why is ice less dense than water? What is the formula for density? 7. If seawater salinity increases, what happens to the density? 8. If SST decreases what happens water density? 9. Is seawater acidic or basic? 10. What is the pH of seawater?Explanation / Answer
1) Polarity and structure of water molecules -
Polarity is charge inequality on two ends of any molecule. Due to the unequal distribution of electrons in water molecule, one part of the molecule is more negatively charged than the other part. This is caused by the property of 'electronegativity', which can be defined as ability of an element to attract electrons. If the atoms that make up a molecule have different electronegativities, that differ substantially, they attract electrons unequally, causing polarity.
The polarity arises due to its peculiar molecular structure. The molecule is made up of one oxygen atom covalently bonded with two hydrogen atoms. A covalent bond is formed when two atoms share electron pairs with each other to achieve stability.
Oxygen has six electrons in its outermost orbit. Out of these six electrons, one electron each is shared with two hydrogen atoms, which themselves only have one electron in the outermost shell. Through covalent bonding, oxygen shares two electrons with hydrogen atoms to form the water molecule. Besides these two shared pairs of electrons, water has two pairs of unshared electrons, that repel the other two bonding pairs with Hydrogen atoms, leading to distortion in its shape.
The polarity arises due to water's greater electronegativity or electron loving nature of oxygen, compared to hydrogen. Even though the pairs of electrons are shared with the hydrogen atoms, they are not shared equally, as oxygen pulls the electrons more towards itself. This gives rise to a greater negative charge on the side of oxygen atom and a positive charge on the hydrogen atoms. That means, water molecule becomes polar because of the greater ability of oxygen to attract electrons toward itself. This polar nature of water molecule gives rise to an electric dipole moment leading to the many peculiar properties of water, like its high surface tension.
Hydrogen Bonding
Due to the polar nature of water, a special kind of bonding occurs between every molecule of water and its surrounding molecules. The negatively charged oxygen atom attracts surrounding hydrogen atoms of other water molecules, which are positively charged, creating a weak bond called the 'Hydrogen Bond'. This hydrogen bonding is responsible for most of the peculiar properties of water.