Caffeine (c8h10n4o2) is a weak base with a pkb of 10.4. part a calculate the ph of a solution containing a caffeine concentration of 430 mg/l .

Look at the spectrums of a star moving towards earth and a motionless star. which of these is a correct inference that can be draw from the observation of the two spectrums? (2 points) the spectrum of a motionless star is difficult to be viewed separately using oridinary telescopes. the spectrum of a motionless star is identical to the spectrum of a star which moves towards earth. the spectrum of a star shifts towards the red region when the star moves towards earth. the spectrum of a star shifts towards the blue region when the star moves towards earth.

What is the approximate vapor pressure when the gas condenses at 70 degrees celsius

Draw the aromatic compound toluene (methylbenzene). show all hydrogen atoms, including those on the ring.