Answer: The enthalpy change for formation of butane is -125 kJ/mol
Explanation:
The balanced chemical reaction is,
The expression for enthalpy change is,
![\Delta H=[n\times H_f{products}]-[n\times H_f{reactants}]](https://tex.z-dn.net/?f=%5CDelta%20H%3D%5Bn%5Ctimes%20H_f%7Bproducts%7D%5D-%5Bn%5Ctimes%20H_f%7Breactants%7D%5D)
Putting the values we get :
![\Delta H=[4\times H_f_{CO_2}+5\times H_f_{H_2O}]-[1\times H_f_{C_4H_{10}}+\frac{13}{2}\times H_f_{O_2}]](https://tex.z-dn.net/?f=%5CDelta%20H%3D%5B4%5Ctimes%20H_f_%7BCO_2%7D%2B5%5Ctimes%20H_f_%7BH_2O%7D%5D-%5B1%5Ctimes%20H_f_%7BC_4H_%7B10%7D%7D%2B%5Cfrac%7B13%7D%7B2%7D%5Ctimes%20H_f_%7BO_2%7D%5D)
![-2877=[(4\times -393)+(5\times -286)]-[1\times H_f_{C_4H_{10}}+\frac{13}{2}\times 0]](https://tex.z-dn.net/?f=-2877%3D%5B%284%5Ctimes%20-393%29%2B%285%5Ctimes%20-286%29%5D-%5B1%5Ctimes%20H_f_%7BC_4H_%7B10%7D%7D%2B%5Cfrac%7B13%7D%7B2%7D%5Ctimes%200%5D)
Thus enthalpy change for formation of butane is -125 kJ/mol
Answer:
Explanation:
There are no molecules in NaCl, because it consists only of ions.
However, we can calculate the number of formula units (FU) of NaCl.
Step 1. Calculate the moles of NaCl
Step 2. Convert moles to formula units
There are 
in 3.6 g of NaCl.
a) Group 2 elements have 2 electrons on their outer shell, so they form a 2+ charge.
b) they lose 2 electrons as they are transferred to the non metal.
c)They obtain this charge as when they are made into an ionic compound the 2 electrons on the outer shell are transferred to the non metal, meaning there are 2 more protons that electrons, giving it a positive charge.
hope this helps! :)
<h3><u>Answer</u>;</h3>
A triple covalent bond because each atom requires three more electrons to complete its octet.
<h3><u>Explanation</u>;</h3>
- A triple covalent bond is a covalent bond formed by atoms that share three pairs of electrons.
- For example;<em><u> in a diatomic molecule such a nitrogen; A nitrogen atom has five valence electrons, which can be shown as one pair and three single electrons. </u></em>When combining with another nitrogen atom to form a diatomic molecule, the three single electrons on each atom combine to form three shared pairs of electrons.
Electron transitions from higher to lower energy levels cause emission of energy in the form of electromagnetic waves, each with their own specific wavelength. Because the energy levels of elements are quantized, each transition has a specific energy difference. The collection of these transitions makes up the emission spectrum and each spectrum is unique to a specific element, allowing identification.
