Answer:
1 gramo de metano aporta 50.125 kilojoules.
1 gramo de metano aporta 48.246 kilojoules.
Explanation:
La cantidad de energía liberada por la combustión de una unidad de masa del hidrocarburo (
), en kilojoules por mol, es igual a la cantidad de energía liberada por mol de compuesto (
), en kilojoules por mol, dividido por su masa molar (
), en gramos por mol:
(1)
A continuación, analizamos cada caso:
Metano


1 gramo de metano aporta 50.125 kilojoules.
Octano


1 gramo de metano aporta 48.246 kilojoules.
Answer:
Balanced chemical equation:
NO₂ + NO₃ → N₂O₅
Explanation:
Chemical equation:
NO₂ + NO₃ → N₂O₅
Balanced chemical equation:
NO₂ + NO₃ → N₂O₅
Nitrogen trioxide gas combine with nitrogen dioxide gas and form nitrogen pentoxide.
This is the simple synthesis reaction in which two substance combine to form a new substance.
Synthesis reaction:
It is the reaction in which two or more simple substance react to give one or more complex product.
General chemical equation:
A + B → AB
A and B are reactants that combine to form AB product.
Compounds Na₂SO₄ and NaCl are mixed together are we are asked to find the concentration of Na⁺ in the mixture
Na₂SO₄ ---> 2 Na⁺ + SO₄³⁻
1 mol of Na₂SO₄ gives out 2 mol of Na⁺ ions
the number of Na₂SO₄ moles added - 0.800 M/1000 * 100 ml
= 0.08 mol
therefore number of Na⁺ ions from Na₂SO₄ = 0.08 * 2 = 0.16 mol
NaCl ----> Na⁺ + Cl⁻
1 mol of NaCl gives 1 mol of Na⁺ ions
number of NaCl moles added = 1.20 M/1000 * 200 ml
= 0.24 mol
number of Na⁺ ions from NaCl = 0.24 mol
total number of Na⁺ ions in the mixture = 0.16 mol + 0.24 mol = 0.4 mol
as stated the volumes are additive,
therefore total volume = 100 ml + 200 ml = 300 ml
the concentration of Na⁺ ions = number of moles / volume
= 0.4 mol/ 0.3 dm³
concentration of Na⁺ = 1.33 mol/dm³
Answer : The correct answer is, (c) the number of neutrons
Explanation :
Isotope : It is defined as the element that have the same number of protons but have the different number of neutrons of each of the atom.
Atomic number is defined as the number of protons or number of electrons.
Atomic number = number of protons = number of electrons
Mass number is defined as the sum of number of protons and number of neutrons.
Number of neutrons = Mass number - Atomic number
For example : For Carbon - 13 isotope.
Mass number = 13
Atomic number = 6
Number of neutrons = Mass number - Atomic number
Number of neutrons = 13 - 6 = 7
Hence, the difference between the mass number of an isotope and its atomic number is the number of neutrons.