Term
| When a reaction results in almost a complete conversion of reactants to products chemists say the reaction |
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Definition
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Definition
| a reaction that can take place both in the forward and reverse directions. May oead to equilibrium if forward and reverse rates are the same |
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Most reactions don’t
They appear to
This is because reactions are |
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Definition
go to completion
stop
reversible |
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Term
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Definition
| a reaction occurring in a closed system, all reactants and products are present and the observable properties remain the same. |
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Definition
| The reactants are forming products at the same rate as the products are forming reactants |
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Term
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Definition
| Equilibrium is a dynamic process because it is in a state of action i/e reactants are changing to products as products are changing to reactants |
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Term
| Conditions required for equilibrium: |
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Definition
1. Constant observable macroscopic properties
2. A closed system
3. Constant temperature and pressure
4. Reversibility |
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Term
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Definition
| A mathematical expression going the ratio of the products to the reactants |
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Term
| Homogeneous vs .heterogeneous equilibria |
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Definition
- Homogeneous system: products and reactants are in the same phase
- Heterogeneous system: products and reactants are in different phases |
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Term
| Note: since the concentrations of solids and liquids are fixed by their densities and do not change during a chemical reaction, it is not necessary to include them in the mass action expression |
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Definition
| just gases and aqueous go in this equation. |
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Definition
| you have more reactants than products at equilibrium |
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Term
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Definition
| you have more products than reactants at equilibrium. |
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Term
| To determine these concentration, we could: |
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Definition
1. Measure the pressure of the gases with a manometer
2. If there is a color change, measure the intensity of the substance to determine the concentration at equilibrium.
3. If there is ionization occurring, measure the electrical conductivity of the solution. |
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Term
| Two factors influence whether or not a system reaches equilibrium |
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Definition
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Term
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Definition
| heat content or Pe(potential energy) of a substance. A system tends to go from a state of higher energy to one of lower energy. |
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Term
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Definition
degree of randomness or disorder
*natural process tend to go from an orderly state to a disorderly one |
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Term
A reaction proceeds in the direction that favours ___enthalpy and_____ entropy
what is equilibrium is these terms? |
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Definition
lowest
highest
Equilibrium is a compromise between these two factors |
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Term
| 1When both factors favour products |
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Definition
| the reaction goes to completion |
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Term
| 2When both factors favour the reactants, |
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Definition
| the reaction doesn’t happen |
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Term
| 3when one favours reactants and the other favours products |
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Definition
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Term
| When a reaction results in almost a complete conversion of reactants to products chemists say the reaction |
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Definition
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Term
Predict which substances have higher entropy
1. Gases or liquids
2. Solids or liquids
3. Dissolved solids and liquids or pure solids and liquids |
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Definition
gasses
liquides
dissolved solids |
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Term
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Definition
| reaction quotient, or trial keq. |
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Term
| To determine which reaction is favoured and in which direction the system is moving, q is compared to keq: |
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Definition
• If keq=k,the system is at equilibrium
• If Q>k, the system is not at equilibrium. There is too much product, so the reverse reaction is favoured to bring the reactant-product
• If Q |
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