Hard question thx for the points
Answer:
A (H)
Explanation:
The key uptop shows all the red are non metal and "H: is pink
The first statement (Matter is neither created nor destroyed) is correct.
The second statement would violate the law of conservation of mass (I will refer to this as LCM), as it would mean matter can "flow" into the universe, but not out, meaning the total matter will never be less than it was before.
The third statement violates LCM because it means matter is created during a reaction, which is not true.
The last statement violates LCM because it means matter is lost during a reaction, which is not true.
Glaze defects are any flaws in the surface quality of a ceramic glaze,it’s physical structure or its interaction with the body.
Answer: +178.3 kJ
Explanation:
The chemical equation follows:
![CaCO_3(s)\rightarrow CaO(s)+CO_2(g)](https://tex.z-dn.net/?f=CaCO_3%28s%29%5Crightarrow%20CaO%28s%29%2BCO_2%28g%29)
The equation for the enthalpy change of the above reaction is:
![\Delta H^o_{rxn}=[(1\times \Delta H^o_f_{(CaO(s))})+(1\times \Delta H^0f_{CO_2}]-[(1\times \Delta H^o_f_{(CaCO_3(s))})]](https://tex.z-dn.net/?f=%5CDelta%20H%5Eo_%7Brxn%7D%3D%5B%281%5Ctimes%20%5CDelta%20H%5Eo_f_%7B%28CaO%28s%29%29%7D%29%2B%281%5Ctimes%20%5CDelta%20H%5E0f_%7BCO_2%7D%5D-%5B%281%5Ctimes%20%5CDelta%20H%5Eo_f_%7B%28CaCO_3%28s%29%29%7D%29%5D)
We are given:
![\Delta H^o_f_{(CaO(s))}=-635.1kJ/mol\\\Delta H^o_f_{(CaCO_3(s))}=-1206.9kJ/mol\\\Delta H^o_f_{(CO_2(g))}=-393.5kJ/mol\\\Delta H^o_{rxn}=?](https://tex.z-dn.net/?f=%5CDelta%20H%5Eo_f_%7B%28CaO%28s%29%29%7D%3D-635.1kJ%2Fmol%5C%5C%5CDelta%20H%5Eo_f_%7B%28CaCO_3%28s%29%29%7D%3D-1206.9kJ%2Fmol%5C%5C%5CDelta%20H%5Eo_f_%7B%28CO_2%28g%29%29%7D%3D-393.5kJ%2Fmol%5C%5C%5CDelta%20H%5Eo_%7Brxn%7D%3D%3F)
Putting values in above equation, we get:
![\Delta H^o_{rxn}=[(1\times (-635.1))+(1\times (-393.5))]-[(1\times (-1206.9))]](https://tex.z-dn.net/?f=%5CDelta%20H%5Eo_%7Brxn%7D%3D%5B%281%5Ctimes%20%28-635.1%29%29%2B%281%5Ctimes%20%28-393.5%29%29%5D-%5B%281%5Ctimes%20%28-1206.9%29%29%5D)
The DH°rxn for the decomposition of calcium carbonate to calcium oxide and carbon dioxide is +178.3 kJ