What is the name of the compound with formula P4O10? What is the name of the compound with formula CoS? What is the name of the compound with formula I2Se5? N-F is a polar bond. Which way are the electrons attracted to:
a. towards N
b. towards F
c. exactly between N and F
d. none of the above
The correct answer and explanation is:
Here are the answers and explanations for each question:
- P₄O₁₀:
- The name of this compound is tetraphosphorus decoxide.
- This is an oxide of phosphorus. The “tetra-” prefix refers to the four phosphorus atoms, and the “deca-” prefix refers to the ten oxygen atoms. The compound is commonly used in the synthesis of phosphoric acid and its derivatives.
- CoS:
- The name of this compound is cobalt(II) sulfide.
- Cobalt can form two different oxidation states, +2 and +3. In this case, the “II” indicates that cobalt is in the +2 oxidation state. The “sulfide” part of the name comes from the sulfur atom, which is in the -2 oxidation state.
- I₂Se₅:
- The name of this compound is diiodine pentaselenide.
- The “di-” prefix indicates two iodine atoms, and the “penta-” prefix indicates five selenium atoms. The compound is formed when iodine reacts with selenium.
- N-F Bond Polarity:
- The correct answer is: b. towards F.
- Nitrogen (N) and fluorine (F) form a polar covalent bond. Fluorine is more electronegative than nitrogen, meaning it has a stronger tendency to attract electrons. As a result, the electrons in the N-F bond are pulled closer to fluorine, making the fluorine end slightly negative (δ−) and the nitrogen end slightly positive (δ+).
Explanation of Polarity:
In a polar covalent bond, the electron density is not equally shared between the two atoms. Electronegativity, a measure of an atom’s ability to attract electrons in a chemical bond, plays a key role. In the case of the N-F bond:
- Fluorine has an electronegativity of 3.98, while nitrogen has an electronegativity of 3.04.
- This difference in electronegativity (3.98 – 3.04 = 0.94) leads to the formation of a dipole, where the electron cloud is more concentrated around fluorine, causing it to be partially negative, and nitrogen to be partially positive.
In summary:
- P₄O₁₀ is tetraphosphorus decoxide.
- CoS is cobalt(II) sulfide.
- I₂Se₅ is diiodine pentaselenide.
- The electrons in the N-F bond are attracted towards F.