How many valence electrons are shared, gained, or lost by each atom of the six compounds? • N2 • CCl4 • SiO2 • AlCl3 • CaCl2 • LiBr

I know this was already asked, but I still do not really get it...

To determine the number of valence electrons shared, gained, or lost by each atom in a compound, we need to first determine the number of valence electrons each atom has.

1. N2: Nitrogen (N) is in group 15 of the periodic table, so it has 5 valence electrons. Since there are two nitrogen atoms in N2, the total number of valence electrons is 2 * 5 = 10. In this case, the electrons are only shared between the two nitrogen atoms, so there is no gain or loss.

2. CCl4: Carbon (C) is in group 14 of the periodic table and has 4 valence electrons. Chlorine (Cl) is in group 17 and has 7 valence electrons. In CCl4, there is one carbon atom and four chlorine atoms. The carbon atom shares four of its valence electrons with each of the four chlorine atoms, making it share 4 * 4 = 16 electrons. The carbon atom does not gain or lose any electrons in this case.

3. SiO2: Silicon (Si) is in group 14 and has 4 valence electrons. Oxygen (O) is in group 16 and has 6 valence electrons. In SiO2, there is one silicon atom and two oxygen atoms. The silicon atom shares two of its valence electrons with each oxygen atom, making it share 2 * 2 = 4 electrons. The oxygen atoms share 4 electrons from the silicon atom. In this compound, the silicon atom does not gain or lose any electrons.

4. AlCl3: Aluminum (Al) is in group 13 and has 3 valence electrons. Chlorine (Cl) has 7 valence electrons. In AlCl3, there is one aluminum atom and three chlorine atoms. The aluminum atom shares its three valence electrons with each chlorine atom, making it share 3 * 3 = 9 electrons. Each chlorine atom shares one electron from the aluminum atom. In this case, the aluminum atom loses 3 electrons and each chlorine atom gains one electron.

5. CaCl2: Calcium (Ca) is in group 2 and has 2 valence electrons. Chlorine (Cl) has 7 valence electrons. In CaCl2, there is one calcium atom and two chlorine atoms. The calcium atom shares its two valence electrons with each chlorine atom, making it share 2 * 2 = 4 electrons. Each chlorine atom shares one electron from the calcium atom. In this case, the calcium atom loses 2 electrons and each chlorine atom gains one electron.

6. LiBr: Lithium (Li) is in group 1 and has 1 valence electron. Bromine (Br) is in group 17 and has 7 valence electrons. In LiBr, there is one lithium atom and one bromine atom. The lithium atom shares its valence electron with the bromine atom. In this case, the lithium atom loses 1 electron, and the bromine atom gains one electron.

To summarize:
• N2: The atoms share 10 valence electrons.
• CCl4: The carbon atom shares 16 valence electrons, and the chlorine atoms share 4 electrons each.
• SiO2: The silicon atom shares 4 valence electrons, and the oxygen atoms share 4 electrons each.
• AlCl3: The aluminum atom loses 3 valence electrons, and the chlorine atoms gain 1 electron each.
• CaCl2: The calcium atom loses 2 valence electrons, and the chlorine atoms gain 1 electron each.
• LiBr: The lithium atom loses 1 valence electron, and the bromine atom gains 1 electron.

Note: Valence electrons are the electrons in the outermost energy level of an atom that are involved in chemical bonding. To determine the number of valence electrons in an atom, you can refer to the periodic table and look at the group number for main group elements.

Thanks!

I suggest you Google "Lewis structure of ???" and for the ??? type in the compound.

For N2 it will look something like this.
:N:::N: Since N is in group V it has 5 electrons in the outside shell or 10 electrons for the two atoms of N. So 6 electrons are being shared by the two N atoms. The others are done similarly.