Answer:
A. True
B. False
C. False
D. True
E. False
Explanation:
A. The proximal histidine covalently binds iron.
This statement is true because the proximal histidine is covalently bonded to the fifth coordination position of iron in myoglobin
B. The distal histidine covalently binds oxygen.
This statement is false because the distal histidine interacts with the oxygen covalently bonded to the sixty coordination position of iron by means of a hydrogen bond not a covalent bond.
C. The distal histidine binds iron
This statement is false because the distal histidine is not bonded to iron but to oxygen but stabilizes the oxygen bonded to iron
D. Free heme binds CO with the Fe, C and O atoms in a linear array.
This statement is true because free heme has more affinity for CO than O2 as it has the least steric hindrance when the Fe, C, and O atoms lie in a straight line. On the other hand, when O2 binds to free heme, the axis of the oxygen molecule is positioned at an angle to the Fe-O bond thereby producing significant steric hindrance.
E. The iron in heme binds the oxygen atom of CO.
This statement is false because the iron in heme binds to the carbon atom, C, of CO rather than to oxygen atom.
The balanced reaction is: 2Mo+3O2>2MoO3
Calculate the number of molecules present in 3.50 mol feo2. 2.11 x 1024 molecules 2.107 x 1023 molecules 3.50 x 1023 molecules <u>3.5*(6.02*10^23)=2.107*10^24 molecules</u>
<h3>What is
molecules?</h3>
A molecule is the smallest unit of a substance that keeps its content and properties. It is made up of two or more atoms that are joined together by chemical bonds. Chemistry is built on molecules. The element symbol and a subscript indicating the number of atoms are used to identify molecules.
The fundamental building block of an element is an atom. They are made up of an electron-surrounded nucleus. An atom is considered to have valence electrons if its electron shell is not completely complete. A chemical (covalent) connection is created and a lower energy state is entered when two or more atoms join forces to share outer shell valence electrons. In an exothermic reaction, energy is released as atoms bond.
To learn more about molecules from the given link:
brainly.com/question/24722507
#SPJ4
N(H₂O)=1g÷18g/mol=0,055mol
N(H₂O)=0,055mol · 6·10²³ 1/mol (Avogadro number)= 3,33·10²² molecules.
Answer:
0.46M NaS₂O₃ (Assuming KIO₃ solution with a concentration of 1.0M)
Explanation:
Based on the reaction:
6 Na₂S₂O₃ + KIO₃ + 5 KI + 3 H₂SO₄ → 3 Na₂S₄O₆ + 3 H₂O + 3 K₂SO₄ + 6 NaI
<em>6 moles of Na₂S₂O₃ react per mole of KIO₃</em>
Assuming the molarity of the KIO₃ solution is 0,1M:
Moles of KIO₃: = 5.0x10⁻³L ₓ (0.1 mol / L) = <em>5.0x10⁻⁴ moles</em>
As 6 moles of thiosulfate reacted per mole of iodate:
5.0x10⁻⁴ moles KIO₃ ₓ (6 moles Na₂S₂O₃ / 1 mole KIO₃) =
<em>3.0x10⁻³ moles of Na₂S₂O₃. </em>In 6.5mL (6.5x10⁻³L):
3.0x10⁻³moles Na₂S₂O₃ / 6.5x10⁻³ L = 0.46M NaS₂O₃