with a symmetry plane are chiral。(
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举一反三
- Compounds with a symmetry plane are chiral
- Which<br/>plane that axial surfaces of folds are parallel to? ____ A: plane<br/>AB B: plane<br/>AC C: plane<br/>BC D: anyone may be possible
- Aroma compounds in food have no relationship with other compounds in<br/>food such as non volatile compounds. ( )
- All<br/>the passengers in the plane that crashed in the middle of the Andes<br/>Mountains a week ago were ______ <br/>as dead.
- Which one of condition is not suitable for influenza virus.() A: +ssRNA B: icosahedral<br/>symmetry C: HA<br/>and NA on surface of envelope D: with<br/>envelope E: growing<br/>in embryonated egg
内容
- 0
Which statement is not true about quinidine ____. A: It<br/>is composed of quinolone ring and quinolone base ring. B: The<br/>two rings are connected by hydroxymethyl. C: Contains<br/>two substituents (methoxy and ethylene) D: It<br/>has four chiral carbons. E: The<br/>target is K+ channel blocker.
- 1
Which of the following<br/>compounds is stable() A: cyclopropane B: cyclobutane C: cyclopentane D: no answer
- 2
My plane ________ at 9 o’ clock tomorrow morning. Will you come to see me off? [br][/br]A) will be leave [br][/br]B) leaves [br][/br]C) will have left [br][/br]D) is left
- 3
Which<br/>of the following techniques is not commonly used for taste compounds<br/>extraction? () A: Solvent extraction; B: Headspace extraction; C: Ultrafiltration; D: Ultrasonic technique
- 4
What’s ______ (comfortable) – travelling by<br/>car, by train or by plane?