<span>When a molecule absorbs a photon, one of its electrons is raised to the excited state</span>
<span>The main difference between carbon-12 and carbon-14 is the number of neutrons present in each compound. Carbon-12 has six neutrons, while carbon-14 has eight neutrons, explains About.com. The differing number of neutrons is responsible for numerous differences between the two compounds.</span>
6.02 x 10^23 moles of representative particles
Answer:
-586.56 kJ/mol is the standard enthalpy of the 3rd reaction.
Explanation:
...[1]
...[2]
..[3]
The unknown standard enthalpy of third reaction can be calculated by using Hess's law:
The law states that 'the heat absorbed or evolved in a given chemical equation is the same whether the process occurs in one step or several steps'.
[2] - 2 × [1] = [3]



The standard enthalpy of the 3rd reaction is -586.56 kJ/mol.The negative sign indicates that energy is released during this reaction.
Answer:
Xe will have the highest partial pressure
Explanation:
Using Dalton's law of partial pressures for ideal gases
p=P*x
where
p= partial pressure , P= total pressure and x = mole fraction = n / ∑n
since the number of moles is related with mass through
n= m/M
where
m= mass and M= molecular weight
then if m is the same for all the gases
x = m*M/ ∑ (m*M) = m*M/ m∑ M = M/∑ M
thus
p=P*x = P*M/ ∑ M
for the 3 gases
p₁=P*x₁ = P*M₁/ (M₁+M₂+M₃)
p₂=P*x₃ = P*M₂/ (M₁+M₂+M₃)
p₂=P*x₃ = P*M₃/ (M₁+M₂+M₃)
then for gasses under the same pressure (P=constant) and same mass (m=constant) , p is higher when the molecular weight is higher . Therefore Xe will have the highest partial pressure