Ask Question, Ask an Expert

+1-415-315-9853

info@mywordsolution.com

Ask Chemistry Expert

Multiple choice problems on Chemical bonding.

1. The chirality of an amino acid, and hence it optical activity, results from the fact that its α carbon is bonded to four different chemical groups. Of the 20 common amino acids, which is not optically active?

a) serine.
b) tryptophane.
c) isoleucine.
d) glycine.
e) glutamic acid.

2. Identify the two amino acids shown below.

2220_amino acids.jpg



A) glycine and asparagine.
B) histidine and lysine.
C) proline and valine.
D) alanine and cysteine.
E) methonine and tryptophane.

3.For the peptide given below, what is its net charge at pH 3? (written N-termàC-term)
Glu-His-Trp-Ser-Gly-Leu-Lys-Gly

Use the following pKa values for the titratable groups:

pKa, N-terminus = 10.0
pKa, Glu, carboxyl side chain = 4.0
pKa, His, imidazole side chain = 6.0
pKa, Lys, amino side chain = 11.0
pKa, C-terminus = 2.0
A) -2
B) -1
C) 0
D) +1
E) +2

4.For the same peptide given in problem #13, what is its net charge at pH 5?
A) -2
B) -1
C) 0
D) +1
E) +2

5.For the same peptide given in problem #13, what is its isoelectric point (pI)?
A) 10
B) 8
C) 6
D) 4
E) 2

6.For the same peptide given in problem #13, what is its sequence (primary structure)?
A) GHTSGLLG
B) GLLGSTHG
C) GKLGSWHE
D) EHWSGLKG
E) GAVLIMPF

7. The absorbance measured for a protein sample at 280 nm was 5. Using an extinction coefficient of 10 cm-1M-1, and a 1 cm path length, find out the protein concentration in this sample.
A) 0.5 M
B) 3 M
C) 1.25 M
D) 5 M
E) 5 mM

8.In what order would the proteins listed below elute from an anion exchange column at pH 6?
Protein A 25 kDa pI = 8.0
Protein B 10 kDa pI = 4.0
A)first A, then B.
B) first B, then A.
C) These proteins would elute together.

9. For the same proteins shown in problem #17, in what order would these proteins elute using gel filtration chromatography?
A) first A, then B.
B) first B, then A.
C) these proteins would elute together.

Identify the type of bond linking amino acids together shown below.

 

2094_bond linking amino acids.jpg

A) hydrogen bond.
B) ion pair.
C) carbon-carbon bond.
D) van der Waals interaction.
E) peptide bond.

Chemistry, Academics

  • Category:- Chemistry
  • Reference No.:- M918963

Have any Question? 


Related Questions in Chemistry

1nbspcalculatenbspthe grams of na2co3nbsprequired to

1. Calculate the grams of Na 2 CO 3   required to prepare 250.0 mL of 0.375 M Na 2 CO 3  solution. 2. The reaction of sodium carbonate with hydrochloric acid produces carbonic acid and sodium chloride. If 25.00 mL of O.0 ...

A 010 m fes04 aq solution is electrolyzed between a

A 0.10 M FeS04 (aq) solution is electrolyzed between a magnesium cathode and a platinum anode with a current density of 1.50 mA cm-2.The hydrogen over potential is 0.60 V. What will be the concentration of Fe2+ions when ...

Chemistry practice examdirections on actual exam the exam

Chemistry Practice Exam Directions on actual Exam: The exam consists of 2 sections (Chemical Bonding and Geometry and IMFs. Each multiple choice question is worth 4.33 points. You are allowed to use a scientific (nonprog ...

Analyzed individually two solutes have retention times of

Analyzed individually, two solutes have retention times of 17 s and 21 s with peak widths at half-maximum (w1/2) of 1.9 s and 2.8 s, respectively. If the two solutes are analyzed together, what would be the resolution on ...

Determine the percent yieldwith respect to co2 and ch4 of

Determine the percent yield(with respect to CO2 and CH4) of the reaction if 1.25g of CO2 was formed by reacting 2.50g of CH4(g) with excess O2 in the reaction: CH4(G) +O2(g) ---->CO2(g) +H2O(g).

Assignmentthe purpose of this assignmentsubmission of an

Assignment The Purpose of this Assignment Submission of an ePortfolio is required for this class. Your Signature Assignment should address topics of personal interest, societal concerns, local, or even global issues, fro ...

A 15-gram sample of neon is placed in a sealed container

A 15-gram sample of neon is placed in a sealed container with a constant volume of 8.5 liters. If the temperature of the container is 27ºC, which of the following expressions gives the correct pressure of gas? The ideal ...

For the reaction between permanganate ion and sufite ion in

For the reaction between permanganate ion and sufite ion in basic solution, the unbalanced equation is: MnO 4 -  + SO 3 2-   MnO 2  + SO 4 2- When this equation is balanced using the smallest whole number coefficients po ...

A sample has a specific heat of 0155 calgmiddotdegc how

A sample has a specific heat of 0.155 cal/g·°C. How much energy will be required to raise the temperature of the sample from 20.0°C to 35.0°C if the sample has a mass of 8.0 g?

When 450 g of an unknown nonvolatile nonelectrolyte is

When 45.0 g of an unknown nonvolatile nonelectrolyte is dissolved in 500.0 g of water, the resulting solution freezes at -0.930 °C. What is the molar mass of the unknown substance? K f  = 1.86 °C/ m  for water.

  • 4,153,160 Questions Asked
  • 13,132 Experts
  • 2,558,936 Questions Answered

Ask Experts for help!!

Looking for Assignment Help?

Start excelling in your Courses, Get help with Assignment

Write us your full requirement for evaluation and you will receive response within 20 minutes turnaround time.

Ask Now Help with Problems, Get a Best Answer

Section onea in an atwood machine suppose two objects of

SECTION ONE (a) In an Atwood Machine, suppose two objects of unequal mass are hung vertically over a frictionless

Part 1you work in hr for a company that operates a factory

Part 1: You work in HR for a company that operates a factory manufacturing fiberglass. There are several hundred empl

Details on advanced accounting paperthis paper is intended

DETAILS ON ADVANCED ACCOUNTING PAPER This paper is intended for students to apply the theoretical knowledge around ac

Create a provider database and related reports and queries

Create a provider database and related reports and queries to capture contact information for potential PC component pro

Describe what you learned about the impact of economic

Describe what you learned about the impact of economic, social, and demographic trends affecting the US labor environmen