MAY 2022 PAST BOARD EXAM
Blue – sure answer; Orange – nasa Handbook; Red – di namin sure
DAY 1 – Physical and Chemical Principles
1. How many hydrogen bonds are there in uracil and adenine? 2 HB
(PBE May 2016)
2. Definition of Organic Ozonolysis. (PBE 2011)
3. The maintenance company, which services PNR railroad lines near
the Pasig River regularly sprays the track casement with a known
herbicide. Because of this, the herbicide concentration in the
area near the railway was detected to be 65 micrograms per liter.
The city of Makati about 18.5 km downstream where the sewage
velocity of the river is 1.2 m/s. Given that the average flow
rate of Pasig River is 53 m^3/s and the constant degradation of
the herbicide is 0.641 per day, estimate the concentration of the
herbicide in the river near Makati. (PBE Nov 2012, Nov 2016, Oct
2021)
4. In a metal plating plant in Cagayan de Oro and Iligan, the waste
contains 20 mg/L Cu2+. It was decided that no precipitate most of
copper in the water, Ca(OH)2 will be used, until only 0.5 mg/L of
Cu remains. Estimate the OH- Concentration in moles/L. (PBE Oct
2021)
The Ksp for this problem is not given. Memorize: Ksp =2 x 10^-19
ANSWER: 1.6 x 10^-7 mol/L
5. Discoverer ng Helium na wala sa choices hahaha. Hula namin Neon
na naman ito, may typo lang siguro. Nasa baba lang kasi si Neon
then yung ibang choices hindi naman applicable kay Helium. You
can check on your PT during exam. Ramsay and Travers sagot namin
ahahahuhu
6. Definition of constitutional isomer. (PBE 2019)
7. Will pine trees grow in Alaska? (PBE 2012 or 2011?)
a. Greenhouse effect
b. Depends on amount of carbon dioxide
