What are the formulas for lithium bromide?

http://www.webelements.com/webelements/compounds/text/Li/Br1Li1-7550358.html

where can i find the formula for cupric nitride,and magnesium chloride also. and what are the formulas for the compounds formed by Fe2+,Cl- how do you figure this out?

You can find the formulas for cupric nitride and magnesium chloride at the same site, although cupric nitride may be harder. I believe that is Cu3N2. The two iron chlorides are FeCl2 and FeCl3.
How do you figures out FeCl2 and FeCl3. You know Cl^- is minus 1 (-1) from your question. Since each compound must be neutral, then Fe+2 and 2Cl^- would make +2 and -2 and that is neutral so FeCl2 is the formula. Fe+3 takes 3 Cl^- to make it neutral (+3 and -3) and the formula is FeCl3.

To find the formulas for specific compounds, you can search for them in reliable sources such as chemistry databases or websites like WebElements. For example, to find the formula for lithium bromide, you can use the link provided: http://www.webelements.com/webelements/compounds/text/Li/Br1Li1-7550358.html

To find the formula for cupric nitride, you could try searching for it in the same database or using a search engine. In this case, cupric nitride is Cu3N2.

Similarly, you can search for the formula for magnesium chloride on websites like WebElements. The formula for magnesium chloride is MgCl2.

To determine the formula for compounds formed by Fe2+ and Cl-, you can use the principle of charge balance. In a neutral compound, the total positive charge must be equal to the total negative charge. Since Cl^- has a charge of -1, in order to balance the charge, one Fe2+ ion combines with two Cl^- ions to form FeCl2. In the case of Fe3+, it takes three Cl^- ions to balance the charge, resulting in the formula FeCl3.