Answer: The molarity of hydroiodic acid in the titration is 0.485 M.
Step-by-step explanation:
To calculate the molarity of acid, we use the equation given by neutralization reaction:
![n_1M_1V_1=n_2M_2V_2](https://img.qammunity.org/2020/formulas/chemistry/middle-school/3skk3sscz961jpcuru5wct9wbqh7zsmdxz.png)
where,
are the n-factor, molarity and volume of acid which is
![HI](https://img.qammunity.org/2020/formulas/chemistry/college/lriw9p40it9rr8z4zv1z031dhnikqox96p.png)
are the n-factor, molarity and volume of base which is
![Ca(OH)_2](https://img.qammunity.org/2020/formulas/chemistry/middle-school/ymprwx7f1b4b6aixd8u2buoexf0b8s4u1l.png)
We are given:
![n_1=1\\M_1=?M\\V_1=20.3mL\\n_2=2\\M_2=0.186M\\V_2=26.5mL](https://img.qammunity.org/2020/formulas/chemistry/college/6mcz6ah25dg68gog6wsvnyr5kb62l09mng.png)
Putting values in above equation, we get:
![1* M_1* 20.3=2* 0.186* 26.5\\\\M_1=0.485M](https://img.qammunity.org/2020/formulas/chemistry/college/h27z841ey3flibkurdjlstlltfdb8r737j.png)
Hence, the molarity of hydroiodic acid is 0.485M.