Asolution with a hydroxide ion concentration of 4.15 × 10-6 m is and has a hydrogen ion concentration of acidic, 2.41 × 10-8 m basic, 2.41 × 10-9 m basic, 2.41 × 10-8 m acidic, 2.41 × 10-9 m

A solution  with  hydroxide ion  concentration  of  4.15   x10^-6 m  is  basic  and  has  a  hydrogen  ion  concentration  of  2.41  x10^-9  M

we  well  know  thaat (H^+)  (OH^-)  =  1  x10^-14

by  making  H^+  concentration  the  subject  of  the formula

H^+  = 1  x10^-14/OH^-
H^+=  1 x10^-14/4.15 x10^-6  =  2.41  x10^-9 M

the solution is basic   since OH^-  ion     is  for  basic solution  

30litre of li2o is 1.0002mole approximately 1 mole

Aphysical change is one that you can put in and remove like a ham sandwich. the stuff you put in there can be changem its not permanet. a chemical change is on that can't be change thats permanet. like when you make a cake and bake it. you can't get those ingredients back.