## Chemistry and Chemical Reactivity (9th Edition)

$n=2$
For this calculation, digits that are not significant numbers will be underlined, and the numbers will have up to 4 decimal places to avoid rounding off errors: $-0.1875=0.2\underline{5}-\frac1{n^2}$ $\frac1{n^2}=0.4\underline{375}$ $n^2=2.\underline{2857}$ $n=1.\underline{5118}$ Rounding to one significant number $n=2$