I need some help to draw a Lewis structure for hydrogen cyanide + what is the noble gas?

Noble Gas: members of Group 18

http://de.academic.ru/pictures/dewiki/72/Hydrogen-cyanide-2D.png

Sure, I can help you with that! To draw the Lewis structure for hydrogen cyanide (HCN), we need to follow a few steps:

Step 1: Count the total number of valence electrons for each atom. Valence electrons are the electrons in the outermost energy level of an atom. Hydrogen (H) has 1 valence electron, carbon (C) has 4, and nitrogen (N) has 5. Since there is only one hydrogen atom and one nitrogen atom, and C has a dual role as both the central atom and a terminal atom, we add up the valence electrons: 1 (hydrogen) + 4 (carbon) + 5 (nitrogen) = 10.

Step 2: Determine the central atom. In this case, carbon (C) is the central atom because it is less electronegative than nitrogen (N). Hydrogen (H) will be a terminal atom, bonded to the carbon, and nitrogen (N) will also be a terminal atom, bonded to the carbon.

Step 3: Connect the atoms with single bonds. Carbon will be bonded to both hydrogen and nitrogen, using single bonds. Since carbon needs four electrons to complete its octet, two more electrons are needed. These extra two electrons will be added as lone pairs on the carbon atom.

Step 4: Distribute the remaining electrons to complete the octets of the atoms bonded to the central atom. In this case, nitrogen already has four electrons from the single bond, so it needs one more electron to complete its octet. This extra electron will be added as a lone pair on the nitrogen atom. Hydrogen needs two more electrons to complete its duet, so each hydrogen atom will have a lone pair of electrons.

Step 5: Check the octet rule. Make sure that all the atoms have their octets filled, except for hydrogen which can have a maximum of two valence electrons.

The resulting Lewis structure for hydrogen cyanide (HCN) is:

H:C:::N

H: represents the hydrogen atom, C::: represents the three bonds between carbon and hydrogen, and N represents the nitrogen atom.

As for your second question, the noble gases are a group of elements found in the far right column of the periodic table. They include helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn). Noble gases are known for being chemically inert, meaning they are very stable and unreactive. This is because their outermost energy level is completely filled with electrons, making them less likely to form chemical bonds with other atoms.