Book+2+2.3

III. Batteries A. transform chemical energy into electrical energy B. Chemical energy is energy stored in chemical compounds i. Luigi Galvani- 1780s- Italian physicist a.) wrong hypothesis ii. Alessandro volta- Italian scientist a.) tweaked/fixed Luigi's idea C. chemical reaction- a process in which substances with different properties 1. volta confirmed by creating an electric battery a.) layered zinc paper soaked in salt water and silver b.) basis for modern batteries c.) produced a current for a relatively long period of time D. electrochemical Cells 1. a device that transforms chemical energy into electrical energy I. consists of 2 different metals- electrolytes- conduct electric current iii. Terminal - part of electrode above the surface of the electrolyte a.) used to connect the cell to the circuit )draw and label pic of battery cell) 2. Chemical reactions occur between the electrolyte and the electrodes in an electrochemical cell I. cause one electrode to be negatively charged and the other electrode to become positively charged, 3. Terminals are connected by a wire, charge will flow from 1 terminal to another i. produces an electric current in the wire 4. Battery - a combination of 2 or more electrochemical cells in a series. i. Several electrochemical cells can be stacked together to form a battery ii. Today -single cells-= "batteries" iii. Total voltage of a battery is found by adding the voltages of a battery is found by adding the voltages the individual cells iv. wet cells- electrochemical cell in which the electrolytes is a liquid a.) car battery v. Dry cell- electrochemical cell in which the electrolytes is a paste a.) flashlight uses dry cells

Quiz 2.3 1. Repeating layers of zinc, paper soaked in salt water and silver 2. a chemical reaction between the electrodes and the electrolyte causes electrodes to become oppositely charged this cause a current in a circuit connected to the terminals 3. total voltage is 6 volts. Total voltage of a battery is the sum of the voltages of the individual cells 4. electrode 5. electrolyte 6. terminal 7. electrochemical cells 8. chemical energy 9. dry cell 10. chemical reaction 11. wet cell 12. battery

Study Guide 3. electrolyte 16. False battery