Question

1. Why do ions like Na+ and Cl- tend to stick together? What kind of bond results from this force?

2. Why do the nuclei of an oxygen atom and two hydrogen atoms remain close together in the structure of a water molecule? What is more stable about a molecule of H2O than three separate atoms of O, H, and H?

3.How is the force holding the water molecule together different from an ionic bond?

4. What makes the covalent bonds in a water molecule polar, while the covalent bond in a hydrogen (H2) molecule is nonpolar?

5. What makes the two sides of a polar covalent bond somewhat different in charge, with one side being somewhat positive while the other is slightly negative?

6. How does the polarity of water molecules affect the properties of water, the substance?

7.What to the terms hydrophilic and hydrophobic mean, and what are some examples of materials are hydrophilic? What are some examples of hydrophobic materials?

8. When a water molecule ionizes, what are the two ionic products? What happens when these two ions get back together?

9. In pure water approximately what proportion of the water molecules are in the state of being ionized (while the rest are regular H2O)?

10. Why does pH go down as acidity increases?

Answer 1

1. Why do ions like Na+ and Cl- tend to stick together? What kind of bond results from this force?

Na+ and Cl- are held together by strong electrostatic attraction forces. Na+ is positively charged and Cl- is negatively charged, therefore due to opposite charges they attract each other.

2. Why do the nuclei of an oxygen atom and two hydrogen atoms remain close together in the structure of a water molecule? What is more stable about a molecule of H2O than three separate atoms of O, H, and H?

a covalent bond exists between atoms of a water molecule. the oxygen atom is an electronegative atom and due to this, it attracts electrons more closely and strongly than hydrogen atoms.

a tetrahedron geometry is more stable about a molecule of water.

3. How is the force holding the water molecule together different from an ionic bond?

water molecules are held together by covalent bonds, in which two or more than two atoms share electrons with each other. in case of an ionic bond, an atom either give or take electrons for stable electronic configuration.

4. What makes the covalent bonds in a water molecule polar, while the covalent bond in a hydrogen (H2) molecule is nonpolar?

water molecule is polar because of bent shaped geometry and also the positive and negative charges on its atoms are evenly distributed between its two of the hydrogen atoms whereas, in the case of the hydrogen molecule, the geometry is linear-shaped and is symmetrical. symmetrical molecules are non-polar.

5. What makes the two sides of a polar covalent bond somewhat different in charge, with one side being somewhat positive while the other is slightly negative?

since water is a polar molecule and the oxygen atom attracts electrons more towards it due to more electronegativity than the hydrogen atoms. this distribution of electrons gives a partial negative charge on the oxygen atom and a partial positive charge on its hydrogen atoms.

6. How does the polarity of water molecules affect the properties of water, the substance?

water is a polar molecule and it dissolves polar substances in it. it is a universal solvent.

polarity of water also affects density when frozen i.e. ice floats on water because it is less dense.

7. What to the terms hydrophilic and hydrophobic mean, and what are some examples of materials are hydrophilic? What are some examples of hydrophobic materials?

hydrophilic means water-loving or water-attracting. hydrophobic means water-repelling or water-hating.

examples of hydrophilic are salts, sugars etc.

examples of hydrophobic are alkanes, oils, fats, etc.

8. When a water molecule ionizes, what are the two ionic products? What happens when these two ions get back together?

when water molecule ionizes it breaks into H+ and OH- ions. when these ions get back then it will create a water molecule.

9. In pure water approximately what proportion of the water molecules are in the state of being ionized (while the rest are regular H2O)?

approximately 80%

10. Why does pH go down as acidity increases?

pH is a measure of hydrogen ion concentration. if the concentration of H+ ions is higher than the pH will be lower and if the concentration of OH- ions is higher than pH will be higher.