Câu 2: (0,5 đ) Tính số ml H3PO4 85% (d=1,69 g/ml) phải lấy để hòa tan vào nước và pha loãng thành 500 ml thì pH = 3.
Biết axit H3PO4 có có pKal=2,15; pKaz=7,31; pKa3= 12,32.

If the atomic mass of an atom is 34 and the atom contains 13 protons, how many neutrons does the atom contain?

Explain the relationship between forward and backward reactions in equilibrium, and predict how changing the amount of a reactant (creating a tension) will affect that relationship.

Two people each hold the end of a rope and create waves by moving their arms up and down. this wave is best classified as a transverse wave because a) both the rope particles and the wave are moving in the same direction. b) the wave is moving up and down as the particles of the rope move horizontally. c) the wave is moving horizontally as the particles of the rope move up and down. eliminate d) the wave is moving in a parallel direction with the motion of the person's arms.