Answer:
Dalton's atomic theory was the first complete attempt to describe all matter in terms of atoms and their properties. Dalton based his theory on the law of conservation of mass and the law of constant composition. ... Parts of the theory had to be modified based on the existence of subatomic particles and isotopes.
Explanation:
Answer:
A food chain shows how energy is transferred from one living organism to another via food. ... When these animals eat these plant products, food energy and organic compounds are transferred from the plants to the animals.
The number of electrons that goes into a Lewis Model is determined by the number of valence electrons
Valence electrons in a covalent bond are shared among the bonded atoms.
Answer:
ΔH = - 254 kJ
Explanation:
The final equation for the enthalpy of formation we want to calculate is:
2 CO₂ (g) + 6 H₂(g) -------------- CH₃OCH₃ (l) ΔH = ?
Notice that if we take the 2 times the first reaction and add the second , by Hess's law we will add the enthalpy changes to obtain our desired ΔH .
( CO₂(g) + 3H₂(g) CH₃OH (l) + H₂O(l); ΔH = -131.kJ) x 2
2CO₂(g) + 6H₂(g) --------- 2CH₃OH (l) + 2 H₂O(l); ΔH = -262.kJ
2CH₃OH (l) --------- CH₃OCH₃(g) + H₂O (l); ΔH = 8.kJ
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2CO₂(g) + 6H₂(g) ----------- CH₃OCH₃(g) + 3H₂O (l); ΔH = -254 kJ