5. Each of the following molecules has the molecular formula C,H,,0 (check for yourself). Which ones are chiral? QH OH (b) OH 6. Draw either one of the enantiomers for each chiral molecule in Problem 5 and label its stereo- center as R or S.

[References] Use the References to access important values if needed for this question. Expressing amounts of energy in different energy units is necessary to solve many chemistry problems. For practice, complete the following table. The Joule (J) is the SI unit of energy. 1 calorie (cal) = 4.184 J J cal kJ 568 149 0.807 Submit Answer Try Another Version 10 item attempts remaining pt pt pt Previous Ne re to search DELL

(CH3)2CHCH,CHO 1. NH3 2. NaCN, HCI 3. HCI, H₂O, heat

Endothermic has a -AH True False

Why shouldn’t a buffer with a pH of 10.0 be used as a mobile phase in an HPLC separation? Group of answer choices Basic pH’s never improve the separation of compounds. At pH’s above 8, the linkage holding the stationary phase on the silica particle degrades. Basic solutions will deprotonate a molecule which makes them impossible to elute from a column. Basic pH’s will cause peak tailing.

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What is the standard heat of formation of C2H4 H2+1/2O2>H2O.   -242kj/mol 2C+3H2+1/2O2>C2H5OH. -273kj/mol C2H4+H20>C2H5OH.    -88kj/mol 2C+2H2>C2H4

2H9O (s) 2Hg (s) + 02 (g) O synthesis O decomposition O hydrocarbon combustion O single replacement O double replacement