Chemistry, 08.12.2021 14:00 anastasialong
Dung dịch X chứa HNO3 0.005M và H2SO4 0.002M có độ pH bằng bao nhiêu
Answers: 2
Chemistry, 20.06.2019 18:04, devoncruz23
Acompound is found to contain 6.1% hydrogen and 93.9% oxygen. find it’s empirical formula.
Answers: 2
Chemistry, 21.06.2019 20:00, Britny2386
2h2s + 3o2 2so2 + 2h2o which option gives the correct mole ratios? h2s: so2 = 2: 2 and o2: h2o = 3: 2 h2s: so2 = 2: 3 and o2: h2o = 3: 2 h2s: so2 = 4: 4 and o2: h2o = 5: 4 h2s: so2 = 4: 6 and o2: h2o = 4: 4
Answers: 1
Chemistry, 22.06.2019 03:50, AysiaRamosLee
What is the temperature of one mole of helium gas at stp?
Answers: 3
Chemistry, 22.06.2019 08:00, katelyn0579
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
Dung dịch X chứa HNO3 0.005M và H2SO4 0.002M có độ pH bằng bao nhiêu...
Social Studies, 14.02.2020 20:58
History, 14.02.2020 20:58
Biology, 14.02.2020 20:58
Chemistry, 14.02.2020 20:58