Energy ChangesDeep Dive

Deep Dive: Breaking and Making Bonds

Part of Bond Energies (HT)GCSE Chemistry

This deep dive covers Deep Dive: Breaking and Making Bonds within Bond Energies (HT) for GCSE Chemistry. Revise Bond Energies (HT) in Energy Changes for GCSE Chemistry with 20 exam-style questions and 15 flashcards. This topic appears regularly enough that it should still be part of a steady revision cycle. It is section 3 of 15 in this topic. Use this deep dive to connect the idea to the wider topic before moving on to questions and flashcards.

Topic position

Section 3 of 15

Practice

20 questions

Recall

15 flashcards

🔬 Deep Dive: Breaking and Making Bonds

Why does breaking a bond always require energy? Think about pulling a magnet off a fridge: you have to put energy in to separate them. Bonded atoms are similar — they are held together by electrical attraction between positively charged nuclei and shared electrons, and you must supply energy to pull them apart. This is why breaking bonds is always endothermic — it always requires an energy input from the surroundings.

The reverse is also true: when atoms come together to form a bond, they move into a lower, more stable energy state and release the excess energy to the surroundings. This is why forming bonds is always exothermic — it always releases energy.

BREAKING Bonds

⬆️

ENDOTHERMIC

Energy is REQUIRED

Energy IN from surroundings

MAKING Bonds

⬇️

EXOTHERMIC

Energy is RELEASED

Energy OUT to surroundings

Keep building this topic

Read this section alongside the surrounding pages in Bond Energies (HT). That gives you the full topic sequence instead of a single isolated revision point.

Practice Questions for Bond Energies (HT)

Which statement correctly describes the energy change when chemical bonds are broken?

  • A. Energy is released to the surroundings
  • B. Energy is absorbed from the surroundings
  • C. No energy change occurs
  • D. Energy may be released or absorbed depending on the bond
1 markfoundation

Explain how you would determine, from a bond energy calculation, whether a reaction is exothermic or endothermic.

2 marksstandard

Quick Recall Flashcards

What are the units for bond energy?
kJ/mol (kilojoules per mole)
What is bond energy?
The energy needed to break 1 mole of a particular bond

20 questions on Bond Energies (HT) — practise free

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