Which of the following is false about a spontaneous chemical reaction that generates electricity: a. oxidation and reduction half-reactions occur at electrodes in electrochemical cells. b. all electrochemical reactions involve the transfer of electrons. c. reduction occurs at the cathode. d. oxidation occurs at the anode. e. all voltaic (galvanic) cells involve the use of electricity to initiate nonspontaneous chemical reactions.

e. All voltaic (galvanic) cells involve the use of electricity to initiate nonspontaneous chemical reactions.

Explanation:

Electrochemical cell or galvanic cell or voltaic cell is a cell which converts chemical energy to electrical energy.

There are two electrodes in an electrochemical cell , where one is called as anode and one is called as cathode.

At cathode reduction takes place and at anode oxidation takes place.Thus the electrons generated at anode travel towards cathode and flow of electrons lead to generation of electricity.

Thus chemical reactions lead to generation of electricity.

Thus the statement that all voltaic cells involve the use of electricity to initiate nonspontaneous chemical reactions is false.

when the volume of gas is   changed from   717.73 ml   to 852 ml   the temperature will   change   from 315   c to 452   c

    calculation

this is calculated using the charles law formula

that is,   v1/t1 = v2/t2

          v1=?

        t1 = 315 c   into   kelvin = 315 +273 = 588 k

        v2 = 852   ml

        t2 = 425c + 273 =698 k

make v1   the subject of the formula ( by   multiplying both side by t1)

  v1=( v2 xt1) / t2

v1= (852 ml   x 588 k)/ 698 k= 717.73 ml