Q1. How many peaks are there in the 13C NMR spectrum of 1,4-dimethylbenzene?

A: 8

B: 4

C: 3

D: 2

Calculate the mass of silver needed to react with chlorine to produce 126g if silver chloride?

Which statement describes the phase change that occurs when dry ice is placed in an open container at room temperature?

Phosphoric acid is a triprotic acid ( =6.9×10−3 , =6.2×10−8 , and =4.8×10−13 ). to find the ph of a buffer composed of h2po−4(aq) and hpo2−4(aq) , which p value should be used in the henderson–hasselbalch equation? p k a1 = 2.16 p k a2 = 7.21 p k a3 = 12.32 calculate the ph of a buffer solution obtained by dissolving 18.0 18.0 g of kh2po4(s) kh 2 po 4 ( s ) and 33.0 33.0 g of na2hpo4(s) na 2 hpo 4 ( s ) in water and then diluting to 1.00 l.