That's because the first and last carbon atoms cannot be branched to form an isomer . Therefore only the three middle carbon atoms can form isomers.
A.)49.4974874 moles or 49.5 moles
B.)2.980808730172671e+25 or 3e+25
The mathematical expression for mass percent is given by:

Put the values,

mass of zinc = 
=
or 65.4 g
Now, number of moles of zinc =
=
= 1.00 mole
Number of atoms of zinc is calculated by the Avogadro number.
Now, according to mole concept
molecules of enzyme consists of
atoms of zinc
So, 1 molecule of enzyme contains =
= 1 atom of zinc.
Hence, every carbonic anhydrase molecule consists of 1 atom of zinc.
The answer is covalent bond
1.39 g HCl
Explanation:
The balanced chemical equation for this reaction is given by
Zn(<em>s</em>) + 2HCl(<em>aq</em>) ---> ZnCl2(<em>aq</em>) + H2(<em>g</em>)
Convert the # of grams of Zn to moles:
1.25 g Zn × (1 mol Zn/65.38 g Zn) = 0.0191 mol Zn
Use the molar ratio to find the # of moles of HCl needed to react completely with the given amount of Zn:
0.0191 mol Zn × (2 mol HCl/1 mol Zn) = 0.0382 mol HCl
Convert this amount to grams:
0.0382 mol HCl × (36.458 g HCl/1 mol HCl) = 1.39 g HCl