Which of the following statements about chemical bonds is TRUE?

Question

Ions (such as Na⁺ and Cl^-) are held together by ionic bonds.Covalent bonds form when electrons are transferred between ions.Water molecules are held together by ionic bonds.Hydrogen bonds are very strong chemical bonds.None of the above.

Answer 1

Think about ionic and covalent bonding like sharing a blanket between two people. The blanket is like the electrons and the two people are the atoms.

1. Ionic bonding is when one person hogs the blanket, leaving the other person without any portion of the blanket
2. Covalent bonding is when both people share the blanket

How strong someone pulls and hogs the blanket is the same as electronegativity (how strongly an atom pulls on nearby electrons). If one person has a lot of strength to pull the blanket to them compared to their partner, this results in them having all of the blanket.

1. This is what happens in the case of Na+ and Cl-. The two atoms have a large difference in electronegativity, resulting in an ionic bond.
2. Note earlier in my analogy. If the blanket is the same as the electrons between atoms, transferring of the blanket, or rather electrons, would be an example of ionic bonding, not covalent bonding.
3. Looking up the electronegativities of the atoms that compose water (H2O), you find that the difference in electronegativity is not large enough to form ionic bonds. Rather, water uses polar covalent bonds.
4. Hydrogen bonding is not a form of bonding like ionic or covalent bonding. Their is no transfer or sharing of electrons. Hydrogen bonding forms between molecules that have strong dipoles. In the case of water, the oxygen has a stronger electronegativity compared to hydrogen. This pulls the electrons more towards oxygen's side. The electrons spend more time on oxygen's side. Remember, electrons are negatively charged. This means that there are areas around oxygen that have a partial negative charge. Vice versa, the hydrogens will have partial positive charges.
5. Hydrogen bonding is the attraction between the partial positive charge of the hydrogen atom of one water molecule and the partial negative charge of an oxygen atom of a different water molecule. This attraction is much weaker compared to the full positive/negative charges of ionic compounds and sharing of electrons in covalent bonding.

Answer 2

NaCl is an example of ionic bonding. In water the ionic bond is considered weak because of the hydration spheres that surround the ions.

Answer 3

The first statement is true. Ions such as Na+ and Cl- are held together by ionic bonds. These types of bonds are not necessarily as strong as the covalent bonds and they actually break apart in water when aqueous in the right conditions. The second statement would be true if it stated covalent bonds are the result of SHARING electrons, not TRANSFERRING. Ionic bonds do more of the transferring of electrons. The third statement would be true if it said that the water molecule or H2O that it's atoms are held together by COVALENT bonds, not IONIC bonds. It's shape is a bent shape. The last statement is in accurate. Hydrogen bonds are not strong bonds but they are actually weaker bonds that happen between 2 or more molecules when there is dipole in the molecule and when the positive end or dipole attracts the negative end or dipole of another molecule. You can observe this when water molecules aggregate or clump together. They arrange themselves in such a way especially in it's solid form or state where you can observe Hydrogen bonds at work, forming a bit of a crystal lattice structure. Hydrogen bonds involve F,O,N, and sometimes S as elemental atoms in molecular bonding. Hydrogen bonds are weak bonds.