Concept explainers
Interpretation:
The Lewis structure of vitamin C is to be drawn and the positions of multiple bonds are to indicated if there any multiple bond.
Concept Introduction:
Lewis structures is also known as Lewis dot structures which represents lines for the bonding between atoms of a molecule and the dots for the lone pairs of electrons that may exist in the molecule.
Covalent bonds are formed by sharing of electrons between atoms.
The valence electrons of Carbon are 4 electrons (requires 4 electrons to achieve octet).
The valence electrons of Oxygen are 6 electrons (requires 2 electrons to achieve octet).
The valence electrons of Hydrogen are 1 electron.
The sharing of one electron from two atoms constitutes a single bond between the two atoms. The sharing of two electrons from two atoms constitutes a double bond between the two atoms
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Fundamentals of General, Organic, and Biological Chemistry (8th Edition)
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- Serine is an uncharged, polar amino acid (below and left). Threonine (below and right) is another uncharged, polar amino acid. Illustrate the hydrolysis of a dipeptide that was made from these two amino acids. Be sure to write all involved reactants and products in the structural form like Serine, and as a proper chemical equation; eg. reactant(s) – product(s). Your diagram of the dipeptide must show the N-terminal and C-terminal ends at opposite sides of the dimer molecule, and you need to indicate where the peptide bond is with an arrow/highlighter. 2. H C-N OH NH, но CH, CH,-CH -C-COOH онarrow_forwardBased on the following titration table of Glycine, would you be able to recreate the same for Histidine? Glicina Increasing pH H-N-CH,-COOH -H-N-CH,-co = H-N-CH,-C00- Net charge: +1 pH COOH-pKa = 2.3 NH3-pka = 9.6 CN AEq +1 +1 2.3 (0.5°-1)+(0.5°0)=-0.5 +0.5 0.5 9.6 -1 (0.5*+1)+(0.5°0)=+0.5 -0.5 1.5 14 Given that the pKas for Histidine are the following: pka1 = 1.82 pKa2 = 9.17 pКаз %3 6.00 pL = 7.59 2.arrow_forwardDraw the complete structural formula of arachidonic acid (Table 23.1) in a way that shows the cis stereochemistry of its four double bonds.arrow_forward
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- Stereochemistry in biological molecules is often denoted by the D- and L- convention, instead of the R- and S- configurations determined by the Cahn-Ingold-Prelog methodology. Naturally occurring a-amino acids are typically in the L-configuration. The Fischer projection of L-alanine is shown. L-alanine H₂N- COOH H- CH3 Identify which structures are equivalent to the L-configuration. CH3 H -NH₂ COOH H COOH NH₂ -CH3arrow_forwardWhich of the following define the stereochemistry of alanine (as per the structure shown)? Note: Functional groups arranged horizontally are facing towards the front, and the functional groups arranged vertically are facing towards the back. СООН + H₂N to OS- Od- CH, OR-arrow_forwardThreonine has two chiral centers. Draw L-threonine and indicate which carbon atoms are chiral. Which carbon atom is responsible for d and L configuration?arrow_forward
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