<span>The oxidation number that is given to chlorine in a chemical combination indicates how many electrons are gained or lost because it is a neutral compound, perchloric acid has a total charge of 0. Hydrogen has an oxidation number of +1,whereas oxygen has an oxidation number of -2. So for the total charge to be 0, 1 hydrogen + 4 oxygen of negative charge added together must equal 0, which will make the oxidation number of chlorine, solving this algebraically +7.</span>
A covalent bond occurs when two atoms share one pair of valence electrons
Brainliest answer please? :)
Answer:
a = double displacement(iii)
b = Single displacement (ii)
c = Synthesis reaction (i)
d = decomposition reaction (iv)
Explanation:
It's not that hard!
Answer:
b
Explanation:
If a cell has transporters that are not well regulated, weak acids or weak bases can accumulate inside the cells and cause stress.
Answer: -134 kJ
Explanation:
The balanced chemical reaction is,
The expression for enthalpy change is,
![\Delta H=\sum [n\times \Delta H_f(product)]-\sum [n\times \Delta H_f(reactant)]](https://tex.z-dn.net/?f=%5CDelta%20H%3D%5Csum%20%5Bn%5Ctimes%20%5CDelta%20H_f%28product%29%5D-%5Csum%20%5Bn%5Ctimes%20%5CDelta%20H_f%28reactant%29%5D)
![\Delta H=[(n_{HNO_3}\times \Delta H_{HNO_3})+(n_{NO}\times \Delta H_{NO})]-[(n_{H_2O}\times \Delta H_{H_2O})+(n_{NO_2}\times \Delta H_{NO_2})]](https://tex.z-dn.net/?f=%5CDelta%20H%3D%5B%28n_%7BHNO_3%7D%5Ctimes%20%5CDelta%20H_%7BHNO_3%7D%29%2B%28n_%7BNO%7D%5Ctimes%20%5CDelta%20H_%7BNO%7D%29%5D-%5B%28n_%7BH_2O%7D%5Ctimes%20%5CDelta%20H_%7BH_2O%7D%29%2B%28n_%7BNO_2%7D%5Ctimes%20%5CDelta%20H_%7BNO_2%7D%29%5D)
where,
n = number of moles
Now put all the given values in this expression, we get
![\Delta H=[(2\times -207)+(1\times 90)]-[(1\times -286)+(3\times 32)]](https://tex.z-dn.net/?f=%5CDelta%20H%3D%5B%282%5Ctimes%20-207%29%2B%281%5Ctimes%2090%29%5D-%5B%281%5Ctimes%20-286%29%2B%283%5Ctimes%2032%29%5D)
Therefore, the enthalpy change for this reaction is, -134 kJ
