Answers: 1
Chemistry, 21.06.2019 20:30
Un cierto gas tiene un volumen de 800ml a 80°c y 600ml a 80°c y 600mmhg de presiĂłn. Âżcual será el volumen del gas a condiciones normales? sĂ el gas es oxĂgeno, Âżcuál será su peso? y Âżcuántas molĂ©culas están presentes en el sistema?
Answers: 2
Chemistry, 22.06.2019 08:00
Straightforward questions answered in the powerpoint slidesreaction: heating the starting materials under refluxwhat does it mean to heat under reflux? why do we choose water as the reflux solvent? what are boiling chips used for? why do we put a condenser on top of the reaction? why do we add heat and let the reaction stir for 30 minutes? why do we add sulfuric acid to the reaction after it cools as opposed to when it’s still hot? separation: filtration of precipitatewhy don’t we do an aqueous and organic extraction in the separatory funnel? why do you rinse the salicylic acid on the filter with ice cold water? purification: recrystallization of salicylic acid (no hot filtration needed)what is the difference in the amount of room temperature water vs. boiling water needed to dissolve the salicylic acid (assume a 1.2 gram yield of salicylic acid)? remember, in the lab if you need x ml of boiling water to dissolve a solid, then you should add a little more (definitely no more than 1.5 times the theoretical amount) to ensure it doesn’t recrystallize prematurely.analysis: melting point of salicylic acidwhat can you conclude if the melting point of the salicylic acid you just synthesized is 152-155oc and the 1: 1 mix of your product and “synthetic” salicylic acid is 151-154oc?
Answers: 1
Chemistry, 22.06.2019 10:50
A100 kmol/h stream that is 97 mole% carbon tetrachloride (ccl4) and 3% carbon disulfide (cs2) is to be recovered from the bottom of a distillation column. the feed to the column is 16 mole% cs2 and 84% ccl4, and 2% of the ccl4 entering the column is contained in the overhead stream leaving the top of the column. calculate the mass and mole fractions of ccl4 in the overhead stream, and determine the molar flow rates of ccl4 and cs2 in the overhead and feed streams. 12. mw_ccla- 153.82; mw_cs2-76.14.
Answers: 3
Chemistry, 22.06.2019 12:00
Which of the following is an example of physical change not a chemical change? a) a log gives off heat and light as it burns. b) a tree stores energy from the sun in its fruit. c) a penny lost in the grass slowly changes color. d) a water pipe freezes and cracks on a cold night.
Answers: 2
If you have a book and a piece of metal, both at room temperature, the metal will fee cold, but the...
Mathematics, 16.07.2019 01:00
Mathematics, 16.07.2019 01:00
Computers and Technology, 16.07.2019 01:00
World Languages, 16.07.2019 01:00
Mathematics, 16.07.2019 01:00
History, 16.07.2019 01:00
History, 16.07.2019 01:00
History, 16.07.2019 01:00
Mathematics, 16.07.2019 01:00
Chemistry, 16.07.2019 01:00