Một hỗn hợp A gồm nahco3, na2co3, k2co3 có khối lượng 46,6 g chia A làm 2 phần bằng nhau Phần 1: tác dụng với dung dịch CaCl2 dư thu được 15 gam kết tủa Phần 2 :tác dụng với dung dịch ca(oh)2 ư thu được 20 gam kết tủa Tính khối lượng mỗi muối trong hỗn hợp A

Imagine that twenty i.u.’s of enzyme z were catalyzing the above reaction for one minute, under vmaxconditions, in a 3.00 ml assay volume. the assay is buffered with 20 mm phosphate buffer, ph 7.60. what will the ph be at the end of that one minute?

How many absorptions would you expect to observe in the 13c nmr spectra of the following molecules? a) 3-chloropentane b) cis-4-methyl-2-pentene

Before it was launched, a helium-filled balloon had a pressure of 201 kpa at a temperature of 27°c. at an altitude of 15,000 m, the pressure had decreased to 2.5 kpa and the temperature had dropped to -14 °c. the volume of the balloon increased to 59.3 m3. what is the original volume of the balloon? 13 m3 0.85 m3 0.077 m3 1.17 m3