Cho muối X vào dd NaOH, đun nóng, thu được một chất khí làm xanh giấy quỳ ẩm. Chất nào sau đây thỏa mãn tính chất của X? A. K2SO4 B. NH4NO3 C. CaCO3
D. FeCl2

Astudent reacts 13 moles of iron with 21 moles of oxygen according to the following equation:

If a gas has an initial pressure of 101kpa and a volume of 10l, then it expands to a volume of 20l, what is the new pressure?

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.