Please explain this, I have no idea how to figure this out.

What molecule or polyatomic ion has the following features.
(a) four bonded atoms, no unshared electrons on the central atom
(b) two bonded atoms, no unshared electrons on the central atom
(c) two bonded atoms, one unshared pair of electrons on the central atom

We can't draw structures on this forum. Try this for answers.

a. CH4, CCl4, CI4, etc.
b. CO2
c. NO2^-

Here is a link for CCl4.
http://www.chemistry.ccsu.edu/crundwell/Galleries/VSEPR/ccl4.html

Here is a link to show the NO2^-.
https://www.google.com/search?q=lewis+structure+NO2^-&hl=en&client=firefox-a&hs=Se3&rls=org.mozilla:en-US:official&tbm=isch&tbo=u&source=univ&sa=X&ei=3_o4UYCUHaSF2gXO2ID4Cw&ved=0CDgQsAQ&biw=842&bih=498

Here is a link for CO2.
https://www.google.com/search?q=lewis+structure+CO2&hl=en&client=firefox-a&hs=Sd3&rls=org.mozilla:en-US:official&tbm=isch&tbo=u&source=univ&sa=X&ei=ofo4UbCCFrO02AWziIHoCA&ved=0CDAQsAQ&biw=842&bih=498

Here is a link for CCl4.

Sure! I'll be happy to help you figure this out. Let's break down each feature and understand what it means.

(a) The first feature states that there are four bonded atoms and no unshared electrons on the central atom. This means we're looking for a molecule or polyatomic ion where the central atom is bonded to four other atoms, and it has no lone pairs of electrons. To find such molecule or ion, we can refer to the periodic table and identify elements that have four valence electrons. Carbon (C) is a good example of an element that can form four covalent bonds without any lone pairs. So, an example of a molecule that satisfies this feature would be methane (CH4), where the carbon atom is bonded to four hydrogen atoms.

(b) The second feature states that there are two bonded atoms and no unshared electrons on the central atom. In this case, we're looking for a molecule or polyatomic ion where the central atom is bonded to only two other atoms and has no lone pairs of electrons. Oxygen (O) is an element that can form two covalent bonds without any lone pairs. So, an example of a molecule that satisfies this feature would be molecular oxygen (O2), where two oxygen atoms are bonded together.

(c) The third feature specifies that there are two bonded atoms and one unshared pair of electrons on the central atom. This means we need to find a molecule or polyatomic ion where the central atom is bonded to two other atoms and has one lone pair of electrons. Water (H2O) is an example that fits this description. The oxygen atom in water is bonded to two hydrogen atoms and also has two lone pairs of electrons, one of which is not involved in bonding.

In summary:
(a) Four bonded atoms, no unshared electrons on the central atom: Example - Methane (CH4)
(b) Two bonded atoms, no unshared electrons on the central atom: Example - Molecular oxygen (O2)
(c) Two bonded atoms, one unshared pair of electrons on the central atom: Example - Water (H2O)

I hope this explanation helps you understand the features and gives you a better idea of how to figure out similar questions in the future!