Answer
NCl₃
Work Step by Step
1. There is .77mg of N and "6.61mg of the chloride." To get the amount of chlorine in the chloride, simply subtract .77mg from 6.61mg. You get 5.84mg Cl.
2. Convert from mg to g. .77mg=.00077g and 5.84mg=.00584g.
3. Get the amount of moles for both N and Cl. Do that by dividing Cl and N, respectively, by the amount of g in each mole. .00077g/14.01g = .000055 mol N. .00584g/35.45g = .000165 mol Cl.
4. After that step, you have N.₀₀₀₀₅₅Cl.₀₀₀₁₆₅. Divide the "subscripts" of N and Cl, respectively, by the smallest subscript, .000055. You should get NCl₃.
