A student measured the pH of solutions if hydrochloric acid and ethanoic acid. Both solutions had the same volume and concentration. The pH of hydrochloric acid was 1.0. The pH of ethanoic acid was 2.9.
The hydrogen ion, H+(aq), concentration of hydrochloric acid was 0.1 mol/dm^3.
The student estimated the hydrogen ion concentration of ethanoic acid.
Which estimate is approximately correct?
A. 0.001 mol/dm^3
B. 0.01 mol/dm^3
C. 0.1 mol/dm^3
D. 1 mol/dm^3

[I need this ASAP please.]