Linked Questions

3 votes
2 answers
5k views

Can a reaction of the form A + B → AB ever be endothermic? [duplicate]

I understand that forming a bond between $\ce{A}$ and $\ce{B}$ is an exothermic process, with negative enthalpy, but won't there be energy required to get $\ce{A}$ and $\ce{B}$ close enough together ...
Joseph Hirsch's user avatar
1 vote
1 answer
467 views

Is there an example of a bond with negative bond enthalpy? [duplicate]

My textbook says bond breakage is "generally endothermic." This implies there are some bonds out there that release energy when broken. Is there a classic example? Perhaps diatomic Helium?
Nova's user avatar
  • 1,772
0 votes
1 answer
108 views

Does it sometimes take energy to create a chemical bond? [duplicate]

Wikipedia says so: Bonds can also be broken apart. Since most bonds require energy to form, they also give off energy when they are broken. But before most bonds break, the molecule has to be ...
harjinder singh sardar's user avatar
-2 votes
2 answers
200 views

Are all bond-forming processes exothermic? [duplicate]

Are all bond-forming processes exothermic? If so, why don't helium form bonds with neon?
DHMO's user avatar
  • 5,035
30 votes
3 answers
15k views

Why are noble gases stable

I was recently asked the question "Why are noble gases stable? with the expectation of providing an answer beyond the general explanation of "they have full valence layers" and I couldn't think of one....
Chris's user avatar
  • 409
10 votes
2 answers
2k views

What happens in an exothermic reaction at the atomic level? [closed]

Exothermic Reactions are those chemical reactions in which heat is released. How does this happen? What I mean is where does the heat energy come from? Which form of energy is converted to heat ...
Rajdeep Sindhu's user avatar
17 votes
1 answer
8k views

Can entropy increase during bond formation?

Recently the question was asked, "Is bond formation “strictly” exothermic?" As a corollary to that question, what is the relationship between entropy and bond formation? Does the entropy of the bond ...
ron's user avatar
  • 85k
1 vote
1 answer
5k views

How is energy released when a chemical bond is formed? [closed]

Chemical reactions are classed as endothermic or exothermic. Defn: exothermic (of a reaction or process) accompanied by the release of heat. The heat is released when the chemical bonds in the ...
DrWill's user avatar
  • 65
1 vote
2 answers
2k views

Are the breaking of bonds simultaneously endothermic and exothermic? [closed]

I understand that energy is NEEDED to BREAK bonds. But don't chemical bonds already have some form of potential energy in them already? So wouldn't it make sense that even though energy is required to ...
user56907's user avatar
0 votes
1 answer
529 views

What is the lewis structure of NO [duplicate]

I am a bit confused about the lewis structure of $\ce{NO}$ The answer from my worksheet is $\ce{N=O}$ with nitrogen having a free radical. But I drew the structure as N triple bonded to $\ce{O (:N#O:)}...
Y-MinG's user avatar
  • 113
4 votes
2 answers
146 views

Maximum Pressure of Covalently Bonded Material

At high enough pressure, atomic material no longer exists, for example under the conditions of a neutron star. Is there a different maximal pressure above which covalent bonds no longer exist?
DavePhD's user avatar
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2 votes
0 answers
78 views

How to visualize an endothermic/exothermic reaction? [closed]

Let’s say X and Y bond together to create XY, where this reaction is exothermic. What I’m visualizing in my head is X and Y floating about with certain speeds, which contributes to their kinetic ...
Gunog Selrack's user avatar
0 votes
0 answers
28 views

Meaning of chemical energy [duplicate]

I am trying to understand the meaning of chemical energy. I saw in my book that chemical energy is stored in the bonds of chemical compounds and when the bonds are untied the chemical energy increases....
Edoardo's user avatar
  • 139