Answer:
-125 kJ
Explanation:
You calculate the energy required to break all the bonds in the reactants. Then you subtract the energy to break all the bonds in the products.
H₂C=CH₂ + H₂ ⟶ H₃C-CH₃
Bonds: 4C-H + 1C=C 1H-H 6C-H + 1C-C
D/kJ·mol⁻¹: 413 612 436 413 347
The formula relating ΔHrxn and bond dissociation energies (D) is
ΔHrxn = Σ(Dreactants) – Σ(Dproducts)
(Note: This is an exception to the rule. All other thermochemical reactions are “products – reactants”. With bond energies, it’s “reactants – products”. The reason comes from the way we define bond energies.)
<em>For the reactant</em>s:
Σ(Dreactants) = 4 × 413 + 1 × 612 + 1 × 436 = 2700 kJ
<em>For the products:</em>
Σ(Dproducts) = 6 × 413 + 1 × 347 = 2825 kJ
<em>For the system</em>
:
ΔHrxn = 2700 - 2825 = -125 kJ
The molecule CO2 have 2 lone pairs located in the oxygen atoms. It has two double bonds also connecting carbon atom to the two oxygen atoms. It does obey the octet rule so the atoms need 8 electrons in each of them that is why electrons are shared.
Answer:
4.96 mol/dm³
Explanation:
From the question,
Mass of NaCl that dissolved in 0.5L of water = 500-346.8 = 153.2 g.
Therefore, 145.2(1/0.5)g of NaCl will dissolve in 1 L of water
mass of NaCl that will dissolve in 1 L of water = 290.4 g/dm³
Molar mass of NaCl = 58.5 g/mol.
Solubility is the amount of substance in mol that will dissolve in 1 L or 1 dm³ Solution.
solubility in (mol/dm³) = solubility in (g/dm³)/molar mass.
solubility in (mol/dm³) = 290.4/58.5
solubility in (mol/dm³) = 4.96 mol/dm³
There are two types of vesicular transport processes, exocytosis and endocytosis. Endocytosis is the process which is involved in the toxin entering the neuron. This process is where cells intake waste or chemical transmitters which are suspended or dissolved in the extracellular fluid around the cell. <span />
