Answer : The mass of
required is 18.238 grams.
Explanation : Given,
Mass of
= 83.10 g
Molar mass of
= 146 g/mole
Molar mass of
= 256.52 g/mole
The balanced chemical reaction is,

First we have to determine the moles of
.

Now we have to determine the moles of
.
From the balanced chemical reaction we conclude that,
As, 8 moles of
produced from 1 mole of 
So, 0.569 moles of
produced from
mole of 
Now we have to determine the mass of
.


Therefore, the mass of
required is 18.238 grams.
<u>Answer:</u> The molecules of oxygen gas that will be reduced to water are 42 molecules
<u>Explanation:</u>
We are given:

The substance having highest positive
potential will always get reduced and will undergo reduction reaction. Here, oxygen will undergo reduction reaction will get reduced.
will undergo oxidation reaction and will get oxidized.
Substance getting oxidized always act as anode and the one getting reduced always act as cathode.
The half reactions follows:
<u>Oxidation half reaction:</u>
( × 4)
<u>Reduction half reaction:</u>
( × 6)
<u>Overall reaction:</u> 
We are given:
Molecules of
= 28
By Stoichiometry of the reaction:
4 molecules of
reacts with 6 molecules of oxygen gas
So, 28 molecules of
will react with =
molecules of oxygen gas
Hence, the molecules of oxygen gas that will be reduced to water are 42 molecules
You could use another word for change can be variable witch means change and if you times the one two more times then you would get four because two time two would be four and times the one would be four.
The valves stop the blood from flowing backwards