The model of the atom where the central core contains protons and neutrons surrounded by a cloud of electrons is best described as a) the bohr model of the atom. b) the modern model of the atom. c) the plum pudding model of the atom. d) the solar system model of the atom.

Abeaker with 2.00×102 ml of an acetic acid buffer with a ph of 5.000 is sitting on a benchtop. the total molarity of acid and conjugate base in this buffer is 0.100 m. a student adds 4.70 ml of a 0.360 m hcl solution to the beaker. how much will the ph change? the pka of acetic acid is 4.740.