Assign oxidation states to the elements whose atoms are underlined in each of the following compounds or ions:
As an example of how it's supposed to be done: KNO3 (N is underlined)
K= +1
N=+5
03= -2, -2, -2
This means that the Oxidation States that the answer is +5.
A) H2PO4^-( P is underlined)
B) NH4+ ( N is underlined)
C) AIH3 ( AI is underlined)
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Cu(s) + 2AgNO3(aq) ——> Cu (NO3)2 (aq) + 2Ag(s)
Both of the NO3 in this equation above have a minus one charge. Figure out the rest.
Place oxidation numbers above each atom in the above equation.
This reaction is depicted in a battery in the figure above.
Why is it important to have a liquid for this reaction to occur? 1-2 sentence.
What would happen if the salt bridge was broken by dropping the battery, for instance? 1-2 sentence.
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The battery can operate for 8 hours. Describe how this battery works and be sure to answer the following questions in your answer:
Which way (left-right or right-left) are electrons flowing?
Is the copper being reduced or oxidized?
What do the strips look like when examined after 8 hours?
1-2 sentences for each question.
A) H2PO4- (P is underlined)
H= +1
P= +5
O= -2
B) NH4+ (N is underlined)
N= -3
H= +1
C) AIH3 (AI is underlined)
AI= +3
H= +1
Cu(s) + 2AgNO3(aq) -> Cu(NO3)2(aq) + 2Ag(s)
Cu: 0
Ag: +1
N: +5
O: -2
It is important to have a liquid for this reaction to occur because it allows the ions to move, facilitating the transfer of electrons between the electrodes.
If the salt bridge was broken, the flow of ions between the two half-cells would be disrupted, preventing the completion of the redox reaction and halting the flow of electrons.
In this battery, electrons flow from Cu to Ag (right-left). Copper is being oxidized, losing electrons to the Ag ions. After 8 hours, the copper strip would have lost mass and appear thinner, while the silver strip would have gained mass and appear thicker.