Question

opposite of dilute hydrochloric acid

Answer 1

I know that concentrated hydrochloric acid is an approximately 38% solution of hydrogen chloride in water.  And I also know that "dilute hydrochloric acid" can be anything ranging from a somewhat less than 38% solution to almost pure water.  Nevertheless, we often see in the literature, and especially in older text books, reference made to "dilute hydrochloric acid".  And I vividly recall from my youth, in the 50s, reagent bottles etched with such labels that contained no other information.  Travelling back to those far off days, before molarity was taught in my part of the world, what is it reasonable to infer was the concentration of hydrochloric acid in such bottles and what concentration were writers, who were no more specific, referring to?  While we're here, let's jump over to the other side and ask the same question about "dilute sodium hydroxide".

Answer 2

Heya !!
opposite of dilute hydrochloric acid is concentrated hydrochloric acid.