H2S (g) can be generated by the following reaction: 2 HCl(aq) + FeS(s) → FeCl2(aq) + H2S(g) What volume (at STP) of H2S gas can be generated from 27.6 mL of 0.291 M HCl and an excess of FeS? V = ___ mL

This is another titration question. When 35.00 ml of phosphoric acid of unknown concentration is titrated with 1.025 M NaOH, and 18.75 ml of NaOH is required to reach the endpoint, what is the molarity of the phosphoric acid?  The reaction is:  H3PO4 (aq) + 3 NaOH (aq)    →    Na3PO4 (aq) + 3 H2O (l)

Calculate the molarity of an NaOH solution from the following titration data.  Be sure the answer has the correct amount of significant figures.  The chemical equation for this titration is as follows: NaOH  +  KHP  ⟶  NaKP  +  H2O NaOH buret reading, inital:  15.27 mL NaOH buret reading, final:     8.32 mL Mass of KHP (204.22 g/mol):  1.1592 g Calculate the molarity of an NaOH solution from the following titration data.  Be sure the answer has the correct amount of significant figures.  The chemical equation for this titration is as follows: NaOH  +  KHP  ⟶  NaKP  +  H2O NaOH buret reading, inital:  15.27 mL NaOH buret reading, final:     8.32 mL Mass of KHP (204.22 g/mol):  1.1592 g

2. Using the procedure described in this module, a student determined the percent KHP in an impure sample of KHP. A 3.150-g sample of impure KHP required 41.50 mL of 0.1352M NaOH solution for titration. (a) Calculate the number of moles of NaOH required for the titration. (b) Calculate the number of moles of KHP present in the impure sample of KHP. (c) Calculate the number of grams of KHP present in the impure sample. (d) Calculate the percent of KHP in the impure sample, using Equation 8. Equation 8: percent KHP in the impure sample, % = ( mass of KHP in the sample,g/ mass of sample analyzed, g) (100%)