Answer:
The value is
![z = 15.7 mg](https://img.qammunity.org/2021/formulas/chemistry/high-school/ip3yqfe195w1k6hqpamn4j0aqzgjukhus3.png)
Step-by-step explanation:
From the question we are told that
The mass of 9-fluorenone is m = 19 mg
The volume of diethyl ether V = 5 ml
The volume of water is
![V_w = 10 ml](https://img.qammunity.org/2021/formulas/chemistry/high-school/ztkid3ectcoklbcty398rumg5i35yueqz7.png)
The equilibrium constant for 9-fluorenone is
![K_p = 9.5](https://img.qammunity.org/2021/formulas/chemistry/high-school/9lztjjv9yjez8to2h4clvh0vttffsbuo99.png)
Generally the equilibrium constant for 9-fluorenone is mathematically represented as
![K_p = ( (z )/(V) )/( (m - x )/(V_w) )](https://img.qammunity.org/2021/formulas/chemistry/high-school/y0g18ue8lnr5n5st5a3aqiamn1yaxc0m0f.png)
Here z is the remaining mass of 9-fluorenone
=>
![9.5 = ( (z )/(5) )/( (19 - z )/( 10) )](https://img.qammunity.org/2021/formulas/chemistry/high-school/zcz8rxnq4e889ncouhg3en7li21egnza4n.png)
=>
![9.5 = (2z)/(19 - z)](https://img.qammunity.org/2021/formulas/chemistry/high-school/82p5l7t92eejijx16vx78lnuad8sfvrazv.png)
=>
![z = 15.7 mg](https://img.qammunity.org/2021/formulas/chemistry/high-school/ip3yqfe195w1k6hqpamn4j0aqzgjukhus3.png)