A standard galvanic cell is constructed in which a Pb2+ | Pb half cell acts as the cathode. Which of the following statements are correct? 1. Pb is oxidized at the cathode.
2. In the external circuit, electrons flow from the Pb2+|Pb compartment to the other compartment.
3. As the cell runs, anions will migrate from the Pb2+|Pb compartment to the other compartment.
4. The anode compartment could be I2|I-.
5. The anode reaction could be Cr2+ -> Cr3+ + e-

answer : third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol

explanation :

let us write down the given equations

equation 1 :

equation 2 :

equation 3 :

let us use hess's law to find out which 2 equations can be added to get the third equation.

let us reverse equation 2 and multiply it by 2. the new equation that we get is,

equation 4 :

let us add equation 1 & 4

the above equation is similar to equation 3 but has different value for dhrxn.

therefore third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol

on passing the small ampere of electric current through the tube made of ar and hg of cfl generates uv rays which excites the fluorescent and thus emits the high radiation by consumption of just 5- 12 w in comparison to incandescent light which requires more power such as around 40 - 55 w to lighten.

moreover the life span of fluorescent or cfl is around 8000 h whereas the life span of incandescent is around 1200 h

hence, the building installed with incandescent lights bears more electricity bill.

idk i'm not smart

explanation:

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