if 150 ml of HNO3 of unknown conceration withmethyl orange indicator present is tritrated with [0.163M]KOH, then the red solution turns yellow after 28.9 ml of the KOH is added. what is the molarity of HNO3 solution.

mL x M = mL x M

To find the molarity of the HNO3 solution, we can use the concept of stoichiometry.

In this titration, the reaction between HNO3 and KOH is:

HNO3(aq) + KOH(aq) → H2O(l) + KNO3(aq)

We know that the volume of HNO3 solution is 150 ml. To calculate the molarity, we need to find the number of moles of HNO3 that reacted with KOH.

First, let's find the number of moles of KOH:
Moles of KOH = Molarity of KOH × Volume of KOH in liters
Moles of KOH = 0.163 M × (28.9 ml / 1000 ml)
Moles of KOH = 0.163 M × 0.0289 L
Moles of KOH = 0.0047087 mol

The reaction between HNO3 and KOH occurs in a 1:1 ratio. Therefore, the number of moles of HNO3 that reacted with KOH is also 0.0047087 mol.

Now, we can calculate the concentration (molarity) of HNO3:
Molarity of HNO3 = Moles of HNO3 / Volume of HNO3 in liters
Molarity of HNO3 = 0.0047087 mol / (150 ml / 1000 ml)
Molarity of HNO3 = 0.0047087 mol / 0.150 L
Molarity of HNO3 ≈ 0.0314 M

Therefore, the molarity of the HNO3 solution is approximately 0.0314 M.