A chemist needs to determine the concentration of a solution of nitric acid, HNO3. She puts 905 mL of the acid in a flask along with a few drops of indicator. She then slowly adds 0.200 M Ba(OH)2 to the flask until the solution turns pink, indicating the equivalence point of the titration. She notes that 235 mL of Ba(OH)2 was needed to reach the equivalence point. Required:
a. How many moles of Ba(OH)2 are present in 225 mL of 0.200 M Ba(OH)2?
b. How many moles of HNO3 are present if 4.50 x 10^2 mol of Ba(OH)2 was needed to neutralize the acid solution? (Express your answer numerically in moles)

See explanation

Explanation:

The equation of the reaction is;

2HNO3(aq) + Ba(OH)2(aq) >Ba(NO3)2(aq) + 2H2O(l)

a) The number of moles of  Ba(OH)2  = 225/1000 *  0.200

= 0.045 moles

From the reaction equation;

2 moles of HNO3 require 1 mole of  Ba(OH)2

x moles of HNO3 require 4.50 x 10^2 mol of Ba(OH)2

x = 4.50 x 10^2 * 2/1

x = 9  x 10^2 moles of HNO3

stupid i wont let you get a chance

explanation:

the ideal gas law equation is as follows

pv = nrt

where p - pressure

v - volume

n - number of moles

r - universal gas constant

t - temperature

so if the pressure, volume and temperature are already known

we are left with n and r

since r is the universal gas constant that has a known fixed value then r too is known

so we are left with 'n'

once we know temperature volume and pressure

we can find the number of moles of gas present using the ideal gas law equation

this is not my own answer, this is an answer for the same question by the user blahblahmali. i do not claim ownership of this account.