It take 42 min for the concentration of a reactant in a first order reaction to drop from 0,45 mol/l to 0,32 mol/l at 25 °C. How long will it take for the reaction to be 90% complete ? A) 130 min
B) 86 min
C) 137 min
D) 284 min

i want the explanation please

In saturated organic compounds, all the bonds between carbon atoms are called?

The melting point of sulfur is 115 °c and its boiling point is 445 °c. what state would sulfur be in at 200 °c?

The characteristics of two different types of reactions are shown below: reaction a: electrons are gained by the atoms of an element. reaction b: protons are lost by the atom of an element. which statement is true about the atoms of the elements that participate in the two reactions? their identity changes in both reaction a and reaction b. their identity changes in reaction a but not in reaction b. their identity changes in reaction b but not in reaction a. their identity remains the same in both reaction a and reaction b.