3446807
Description
Flashcards by Fiona Heathcote, updated more than 1 year ago
|
Created by Fiona Heathcote
over 8 years ago
|
|
| Question | Answer |
| A chemical that oxidises another substance is called an... | oxidant/ oxidising agent |
| A chemical that reduces another substance is called a.... | reductant/ reducing agent |
| A Daniell cell consists of - | Copper half cell Zinc half cell Salt bridge (internal circuit) External circuit |
| In a Daniell cell, energy is converted from ______________ to _______________. | chemical to electrical |
| The Daniell cell is an example of ... | ...a galvanic cell |
| A half cell is... | ...half an electrochemical cell containing an oxidant and the conjugate reductant. |
| A galvanic cell is formed from the combination of ... | ...two half cells |
| A galvanic cell is... | ...an electrochemical cell. It converts chemical energy into electrical energy. |
| In a galvanic cell, the flow of electrons creates ... | ... an electric current |
| In each half cell, the species present form a ... | ...conjugate pair |
| In general, if one member of the conjugate redox pair in a galvanic cell is a metal, it will be used as the ... | ...electrode |
| If there is no metal present in a half cell, what type of electrode is used? | Inert. Platinum or carbon/graphite. |
| If one member of the conjugate redox pair is gas, what kind of electrode is used? | A special gas electrode which contains a platinum electrode |
| Half cells usually contain spectator ions. What is a spectator ion? | Ions that remain in solution and are unchanged in the course of a reaction. |
| In galvanic cells, the electrode at which oxidation takes place is called the ... | ...anode |
| In galvanic cells, the electrode at which reduction occurs is called the ... | ... cathode |
| In a galvanic cell the anode, where electrons are produced, has a polarity that is ... | ...negative |
| In a galvanic cell the cathode, where electrons are consumed, has a polarity that is ... | ... positive |
| What is the purpose of the salt bridge? | Without the salt bridge, one half cell would accumulate positive charge and the other would accumulate negative charge. Accumulation of charge prevents further reaction. |
| The salt bridge contains ... | ... ions that are free to move to balance charges formed in the half cells. |
| The salt bridge is also called the ... | ... internal circuit |
| The electrochemical series is ... | ... a list of chemical species arranged in decreasing order of their strengths as oxidants |
| Zinc loses electrons more readily than copper. Zinc cations are less likely to accept electrons than copper cations. This makes zinc a stronger ____________ than copper. | reductant |
| The electrochemical series is valid for which conditions? | Standard laboratory conditions: - temperatures of 25 deg celsius - 1 atm - 1M solutions |
| In galvanic cells, the stronger reductant is the half cell with the positive/negative electrode? | negative |
| In galvanic cells, the stronger oxidant is the half cell with the positive/negative electrode? | positive |
| The higher of the two half cell reactions in the electrochemical series goes forward/backward. | forward |
| The lower of the two half cell reactions in the electrochemical series goes forward/backward. | backward |
| Oxidation involves the loss/gain of electrons | loss |
| Reduction involves the loss/gain of electrons | gain |
| True or false? The movement of ions from the salt bridge into the half cell maintains electrical neutrality. | True |
| In a galvanic cell the stronger oxidant will be oxidised/reduced and the stronger reductant will be oxidised/reduced. | reduced oxidised |
| A current flows in a galvanic cell because one half cell has a greater tendency to push electrons into the external circuit than the other half cell. This is called the ... | - potential difference - emf |
Want to create your own Flashcards for free with GoConqr? Learn more.