Answer: The half-reactions represents reduction are as follows.
Explanation:
A half-reaction where addition of electrons take place or a reaction where decrease in oxidation state of an element takes place is called reduction-half reaction.
For example, the oxidation state of Cr in 
is +6 which is getting converted into +3, that is, decrease in oxidation state is taking place as follows.
Similarly, oxidation state of Mn in 
is +7 which is getting converted into +2, that is, decrease in oxidation state is taking place as follows.
Thus, we can conclude that half-reactions represents reduction are as follows.
Answer:
runoff is he draining away of water (or substances carried in it) from the surface of an area of land, a building or structure, etc.
Explanation:
Brass is an alloy, or a combination of two (or more) metals.
Answer:
THE PERCENT ERROR IS 5.55 %
Explanation:
To calculate the percent error, we use the formula:
Percent error = Found value - accepted value / accepted value * 100
Found value = 2.85 g/cm3
Accepted value = 2.70 g/cm3
Solving for the percent error, we have:
Percent error = 2.85 g/cm3 - 2.70 g/cm3 / 2.70 g/cm3 * 100
Percent error = 0.15 / 2.70 * 100
Percent error = 0.05555 * 100
Percent error = 5.55 %
In conclusion, the percent error is 5.55 %
