Can someone help me out please? Honesty

m=9

step-by-step explanation:

7m+8=71 subtract   8 from 71 which is 63 than divide it by 7m   equal 9.

                             

All the elements are arranged by melting points on the periodic table. in row they go from metals to gasses. in the row from sodium to argon, sodium is more reactive than the one on its right, magnesium.

Answercanyon;

Self-ionizes to form an equilibruium system in which [ h_{3} o^{+} ]=[ oh^{-} ]=10^{-7} m