Answer:
Explanation:
4NH₃ (g) + 3O₂ (g) ⇒ 2N₂ (g) + 6H₂ O(1)
Δ
ΔH r =(2ΔH f(N 2 )+6ΔH f (H 2 O(l)))−(4ΔH f (NH 3 (g))+3ΔH f (O 2 (g)))
ΔH rex =[2×0+6×(−286)]−[4×(−46)+3×0]=−1716+186
ΔH rex =−1532kJ/mol
Thermodynamics is a branch of physical chemistry that studies heat and its effects and interactions. Governed by the four main laws, thermodynamics plays a huge role in physics and chemistry, and is also responsible for the law of conservation of energy, a fundamental rule in science.
Answer:
Modern chemistry describes the composition, structure, and physical and chemical properties of substances. ... The main aim of modern chemistry is to improve the communication and conversation among the scientists, researchers, engineers, and policymakers, who are working under the area of modern chemistry
Explanation:
I hope this helps you!!
Answer:

Explanation:
Hello there!
In this case, since the vaporization process is carried out in order to turn a liquid into a gas due to the addition of heat, we can use the following heat equation involving the heat of vaporization of water or any other substance:

Thus, since this heat of vaporization for water is 2259.36 J/g, we plug in this amount to obtain the total energy for this process.

Which is positive due to the necessity of heat.
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Zeff = Z - S
Here, Z is the number of protons in the nucleus, that is, atomic number, and S is the number of nonvalence electrons.
For boron, the electronic configuration is 1s₂ 2s₂ 2p₄
Z = 5, S = 2
Zeff = 5-2 = +3
For O, electronic configuration is 1s₂ 2s₂ 2p₄
Z = 8, S = 2
Zeff = 8-2 = +6
Hence, the correct answer is second option, that is, +3 and +6, the Zeff of boron is smaller in comparison to O, thus, boron exhibits a bigger size than O.