Answer:
not 100% sure but I think it's unbalanced chemical
Answer:
C. Potassium-19
.
Explanation:
Hello!
In this case, since isotopes are known be atoms of the same element with equal atomic number but different mass number, we can consider the case of carbon which has two natural occurring ones, carbon-12 and carbon-13 whereas carbon-12 has the greatest abundance. However, isotope notation may take two forms:
1. Symbol of the element followed by a dash indicating the mass number of the isotope, for instance: C-12, K-39, and so on.
2. Name of the element followed by a dash indicating the mass number of the isotope, for instance: Carbon-12, Potassium-39, and so on.
In such a way, the improper isotope notation is C. Potassium-19
, considering that A should be K-39 because atomic symbol of potassium is K, not k.
Best regards!
The paper in the straw makes the soda fizz.
Answer: The standard enthalpy of formation of this isomer of 
is -210.9 kJ
Explanation:
The given balanced chemical reaction is,
First we have to calculate the enthalpy of formation of 
.
![\Delta H^o=[n_{CO_2}\times \Delta H_f^0_{(CO_2)}+n_{H_2O}\times \Delta H_f^0_{(H_2O)}]-[n_{O_2}\times \Delta H_f^0_{(O_2)+n_{C_8H_{18}}\times \Delta H_f^0_{(C_8H_{18})}]](https://tex.z-dn.net/?f=%5CDelta%20H%5Eo%3D%5Bn_%7BCO_2%7D%5Ctimes%20%5CDelta%20H_f%5E0_%7B%28CO_2%29%7D%2Bn_%7BH_2O%7D%5Ctimes%20%5CDelta%20H_f%5E0_%7B%28H_2O%29%7D%5D-%5Bn_%7BO_2%7D%5Ctimes%20%5CDelta%20H_f%5E0_%7B%28O_2%29%2Bn_%7BC_8H_%7B18%7D%7D%5Ctimes%20%5CDelta%20H_f%5E0_%7B%28C_8H_%7B18%7D%29%7D%5D)
where,
We are given:
Putting values in above equation, we get:
![-511.3kJ/mol=[(8\times -393.5)+(9\times -241.8)]-[(\frac{25}{2}\times 0)+(1\times \Delta H_f^0_{(C_8H_{18})}](https://tex.z-dn.net/?f=-511.3kJ%2Fmol%3D%5B%288%5Ctimes%20-393.5%29%2B%289%5Ctimes%20-241.8%29%5D-%5B%28%5Cfrac%7B25%7D%7B2%7D%5Ctimes%200%29%2B%281%5Ctimes%20%5CDelta%20H_f%5E0_%7B%28C_8H_%7B18%7D%29%7D)
Gold is a element. Hope this helps
