Bond Enthalpies

[Reece Fong 2k]

Are bond enthalpies always positive? In what case would we use them to get a negative number?

[Sanjana Sivakumar 2E]

Hello!

Bond enthalpies are always positive because we need to add energy in order to break bonds. I believe bond enthalpy will be negative if we are forming a bond.

Hope this helps!

[AlexandriaHunt2J]

To add on, for calculating/estimating the change in enthalpy of a reaction using bond enthalpies, you'd have to take the (bond enthalpies for bonds broken) - (bond enthalpies for bonds formed). The negative sign is necessary because it ensures that the sign for the enthalpies of bond formation is negative (which makes sense as energy is released when bonds are formed).

[Katryn Heine 3A]

Bond enthalpy is the amount of energy stored inside a bond and it is always positive it is describing the amount of energy that'd be required to break that bond.

[Ellie Fox 2K]

Just adding on to previous posts, bond enthalpies are always positive because it is the energy required to break the bond which means energy needs to be put in and therefore is positive.

[Jillian Sarquiz- 2B]

Bond enthalpies are positive because they are the energy required to break a bond. If a bond is formed, then energy is released so that energy value is negative (negative bond enthalpy value).

[Alyssa Cua 2J]

Hello!

Bond enthalpies are always positive because we need to add energy in order to break bonds. I believe bond enthalpy will be negative if we are forming a bond.

Hope this helps!

This was a great explanation, and really helped me understand. Thanks so much!

[Ryan Blaydon 1K]

Just as energy is required to break intermolecular forces it is also required to break bonds. Bond enthalpies are always going to be positive because energy needs to be put in to break a bond.

[305589333]

It requires energy to break bonds but it is negative if we are forming a bond

[emily3L]

Bond enthalpies are positive because they are the amount of energy required to break bonds of the compound. This number is negative when the bonds are being formed.

[505749458]

Bond enthalpies are a representation of how much energy is stored in a bond, so it's positive when the bond breaks and energy is released, and negative when energy is required to form that bond.

[Russell Chuang 1J]

Bond enthalpies are always positive. They end up being negative when we are taking the products of them and subtracting the reactant bond enthalpy values.

[005493723]

They will always be positive since in order to break a bond you need to add energy!

[Misha_Khan_2H]

Yes, bond enthalpies are always positive as you require energy to break bonds. They are not negative in any case.

[Harshitha_Pandian_3F]

They will always be positive because in order to break a bond you need to add energy.

[Macy_Anderson_2F]

Bond enthalpies are always positive because it requires energy to break a bond (endothermic process which have positive enthalpy values)

[105778693]

Bond enthalpies are always positive since we add energy in order to break bonds.

[Isabella Perez Dis3L]

Hi, bond enthalpies are positive because it is the energy required to break a bond. When a bond is formed, energy is released so therefore in this case the bond enthalpy value would be negative.

[maya 3f]

Yes, bond enthalpies are always positive since energy is required to break the bond!

[amreen_sandhu1k]

I've been reading the responses to these questions and I have a follow up question because I'm a little confused but does forming a bond result in negative bond enthalpy?

[Monse Mata 3D]

As previously stated, bond enthalpies are ALWAYS positive because energy is required to break bonds.

[Vanessa Bartoli 1C]

Hello,

The definition of a bond enthalpy is the amount of energy that is stored within a bond, meaning when a bond is broken, there is an amount of energy that is released, resulting in a positive value, this is why bong enthalpies are always positive.

Hope this helps!

[105743571]

By definition, Bond enthalpy is the amount of energy required to break 1 mole of a certain bond between two elements. Breaking bonds is an endothermic bonds which will be always positive.

[305607822]

That's why the equation for reaction enthalpy is (bonds broken) - (bonds formed) or Hf (reactants) - Hf (products) because reactants are being broken and products are being formed.

[Chelsea Tran 3H]

Bond enthalpies will always be positive when breaking a bond since an input of energy is required, and thus will be negative when forming a bond since energy will be released.

[Amy Huynh 1B]

They are always positive because bond enthalpies are just the amount of energy needed to break a bond.

[Bailey Herbert 2L]

Since we add energy to break bonds the bond enthalpies would be positive:)

[Nathan Morgan 2C]

We cannot break bonds unless we add energy. Because we are adding energy, bond enthalpies will be positive.

[Aeson Salcedo 3L]

Yes bond enthalpies are always positive because they are they amount of energy needed to break a bond.

[azurexrose]

Bond enthalpies are always positive because it takes energy to break a bond.

[azurexrose]

Bond enthalpies are always positive because it takes energy to break a bond, so it's kind of like an endergonic process.

[Renga Rengappa 1D]

They’re positive because we add energy to break bonds.

[Jeff Balian 2D]

What is the best way to know which bonds enthalpies to add or subtract when trying to find the total enthalpy of a reaction?

[Hamna_Khan_2E]

Hi!

Since energy is required to break chemical bonds, bond enthalpies are always expressed as positive numbers.

Hope this helps!

[Kabir Rahal]

Bond enthalpies are always positive since energy is always used to break apart bonds, and is turned negative when accounting for products in a chemical equation, since the bonds are being formed, not broken.

[Stephanie Rodas 2C]

Since we need energy to break bonds, then the bond enthalpies will always need to be positive.

[505468108]

Hi!
Breaking bonds requires energy - thus a positive bond enthalpy value
Building bonds releases energy - thus a negative bond enthalpy value