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An E.coli cell acquires a mutation in the lacI gene that results in permanent repression of the lac operon. Which of these would characterize such a mutant?

REQUIRED- You will want to draw the Lewis structure of CS2 on your scrap paper before beginning.  From the Lewis structure of CS2 answer the following:  A. Describe the Lewis structure of the molecule and determine what the molecular geometry (name the shape) of the molecule would be?    Bonus- B. Would CS2 be a polar or non-polar molecule?

Calculate the pH of the following solutions of strong acid or strong base:  0.0085 M HCl

Determine the chemical formula if the following combined to form an ioniccompound- if the ions are not written- you must first determine what charges the atoms become when they become an ion- then determine the correct ratio of cation to anion- where electroneutrality will exist.   Al3+ and PO43-   Be sure to use the subscript and superscript feature to correctly express the formula in the correct format. 

Which of the following regulatory elements is NOT a sequence of DNA?

Which amino acid would be attached to the tRNA molecule shown below?

A researcher is studying the effects of increasing the amount of acetylation of histone tails in a culture of human cells. Which of the following results would she most likely see?

Calculate the average atomic weight from the following natural abundance data:    Atomic Symbol     Atomic Mass (amu)     Percent Abundance (%)     Report your answer in amu, to 2 decimal places. 

If the amount of O2 given in question 1 reacts with your given amount of Na in question 2, which is the limiting reactant AND what is the maximum amount (in grams) of Na2O that can be produced? Why?    *You can also use this space to explain how you did question 1 and 2 for partial credit. 

Required- Explain how you did the problem above. Be sure to either show all of your math or explain each conversion step you did in words.