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General reaction laboratory

Choose reviewed reactants and conditions, observe products, balance atoms, calculate stoichiometry and inspect the energy change.

SchoolLive

Scientific learning path

  1. 01UnderstandLive
  2. 02ExploreLive
  3. 03ExperimentLive
  4. 04ObserveLive
  5. 05ExplainLive
  6. 06ApplyLive
  7. 07TestLive
Explanation mode

Interactive experiment

Live

H2(g) + Cl2(g) → 2 HCl(g)

Observation

Start the model to reveal the expected macroscopic observation.

Theory

Light initiates homolytic chlorine-bond cleavage and a radical chain converts H2 and Cl2 into HCl.

Balance

Building

Edit coefficients only. Subscripts identify the substances and must not change.

H2+Cl2→HCl
Cl2 before · 1 afterAdjust
H2 before · 1 afterAdjust

Calculation

Reaction extent
1.000 mol
Standard ΔH
-184.6 kJ
HCl produced
2.000 mol

ΔH° = -184.6 kJ per 1 mol H2 and 1 mol Cl2 consumed; scaled by reaction extent.

Energy change

ReactantsProductsΔH°

Procedure

  1. Select the first and second reactants.
  2. Set the amount of the first reactant.
  3. Select the reviewed reaction condition.
  4. Start and record the observation.
  5. Balance with coefficients, then compare atom totals.
  6. Use reaction extent to calculate product amounts and energy.

Result

Complete the interactive experiment to state a result.

Viva

  • Why can coefficients change while subscripts cannot?
  • Which reactant would limit the reaction if the second reactant were not supplied in its required ratio?
  • What does a negative standard enthalpy change mean?

Quick test

What must remain equal on both sides of an ordinary chemical equation?

Scientific references

Live
  • Atkins, de Paula & Keeler, Atkins’ Physical Chemistry, 11th ed.
  • NIST Chemistry WebBook — thermochemical reference data.

Description of this simulation

Choose two reactants, the amount and a suitable condition, then start the reviewed formation of hydrogen chloride model.

Quick test · 3 questions
1. Which statement is evidence from this simulation?
2. How should you test the effect of one control?
3. Why read the model notes?

Reaction learning path

8 of 17 reviewed reactions

Open foundation-to-advanced path

Objective

Connect a balanced equation to visible products, stoichiometric amounts and the sign of the energy change.

Safety

Live

Hydrogen-chlorine mixtures can react explosively; hydrogen chloride is corrosive. Simulation only.

This screen is a simulation, never a substitute for supervised laboratory risk assessment.

Chemicals

H2(g) + Cl2(g)

Apparatus

  • Shielded photochemical vessel
  • Light source
  • Gas controls
  • Pressure sensor

What this model shows — and what it simplifies

Educational Model

This is a closed, stoichiometric teaching model.

Where do we see this in real life?

Hydrogen chloride is a major industrial chemical and becomes hydrochloric acid when dissolved in water.

Explain this result

Scientific review record

Building
Module version
v1 bundled
Published
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Last reviewed
Not yet verified
Academic level
School
Reviewer
Not publicly assigned

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