1: The IR spectrum of a compound with the formula C3H6O has no strong absorptions between 1600-1800 cm^-1 region nor any strong absorptions above 3000cm^-1. What functional group is it likely to contain? 2: NBS 1-Methylenecyclohexane --------------- >? H2O (Water) 3: A: A low-resolution mass spectrum gave a molecular ion at m/z = 122. Propose two molecular formulas for the molecular ion: one containing nitrogen and another containing three nitrogens. B: A high-resolution mass spectrum provided an exact mass of 121/089149. Which of the two molecular formulas is the correct one? C: How many degrees of unsaturation are in this compound?
1: Ether 2: 1-(Bromomethyl)cyclohexanol 3: A: 121/12=10 10*12=120 121-120= 1 remanding +12H. +1N C10H1----> C9H13 ----> C8H11N -1C. -CH2 and +1N. +1N C8H11N----------> C7H9N2 ----------> C6H7N3 -CH2. -CH2 B: C8H11N C: 2(8)+2= 18 18-[11-1]=8 8/2= 4 degrees of unsaturation.
1: What is the outer shell of electrons referred to as? 2: Propose a plan to make a solution of 3M Sodium Acetate in 40 mL of Water. 3: Which atom is the most electronegative, what effect does it have on radius?
1: Valence electrons 2: Sodium Acetate MW: 82.03g/mol 40 mL--> L= 0.04L M= (mol/L) so........ 3M=(mol/ 0.04L) Next find mol using the equation above. 0.04L * 3M= (mol/0.04L)*0.04L=.1200 mol Next convert .1200 mol into grams of sodium acetate. .1200mol*(82.03g/1mol)= 9.8436g sodium acetate. 3: Fluorine and it will cause the radius of the atom to be small.
1: What are the four major ways enzymes catalyze reactions? 2: What direction are nucleotides added from when making a DNA strand and how do the processes of leading and lagging strands differ when adding nucleotides. 3: Explain the process of RNA interference (RNAi).
1: They arrange reactants in proper orientation to come together, stretch reactants to break bonds, change the environment (pH) to facilitate a chemical reaction, or the enzyme can directly participate by forming a brief covalent bond. 2: Nucleotides are ALWAYS added from 3' to 5'. The leading strand adds nucleotides continuously whereas the lagging strand adds nucleotides in pieces to make Okazaki fragments. 3: During RNAi (the mechanism is shown in Fig 1.1), the dsRNA (double-stranded RNA) associates with Dicer, an endonuclease (an enzyme that cleaves phosphodiester bonds within nucleotide chains), which lyses the duplexed strands to an approximate 19-25 nucleotide base pairs to constitute siRNA (small interfering RNA). The siRNA proceeds to interact with Argonaute protein (AGO), binding the guide strand which is complementary to the target mRNA (messenger RNA) sequence to AGO, forming the RNA Induced Silencing Complex (RISC), meanwhile leaving the passenger strand behind. RISC then pinpoints and binds to the mRNA target site in the cell, promoting AGO- mediated cleavage resulting in gene silencing.