Buffers - mixtures of conjugate acid and conjugate base at ±1 pH unit from pH = pKa. Resistant to changes in pH in response to small additions of H+ or OH-. ... Polyprotic acids - dissociation of each H+ can be treated separately if the pKa values are different
Answer:

Explanation:
The molar mass of uranium-235 is 235 g/mol. So one mole of uranium-235 has a mass of 235 g. Put differently 6.022×10^23 atoms of uranium-235 have a mass of 235 g. Knowing that, how can we use that to find the mass of one atom?
mass of one atom = 
Hi there!
Rutherford's experiment showed that the atom's nucleus <em>did </em>have a positive charge. The α particles' trajectory was altered when it went through the gold foil, which, in turn resulted in the discovery of the atom's positive charge.
I hope this helps!
Brady