It has lost electrons as electrons are negatively charged particles, hence a loss of electrons will leave the rod positively charged.
The first step is to write the balanced equation of the dissociation of the monoprotic weak acid. This can be assumed to have 1:1 stoichiometric relationships, so the equation and ICE chart are given by:
HA ---> H^+ + A^-
initial 0.25 0 0
change -x x x
equilibrium 0.25-x x x
This gives an expression for Ka given by:
Ka = (x)^2/(0.25-x) = 5.4x10^-6
x = 1.159x10^-3 = [H+] = [A-]
pH = -log[H+] = -log[1.159x10^-3] = 2.936
Formation
I remember having this question on a quiz a while back
First line: The atomic number is the whole number on the periodic table so atomic number 35 means the element is bromine. Thus the element symbol is Br. The atomic number is also the number of protons in the isotope so the number of protons is 35. The mass number is the sum of protons and neutrons in the isotope so the mass number is 35+46 or 81. The mass number gives you the top left number on the nuclear symbol (it will look the same as the one below it except the 79 is an 81). Lastly, the number of electrons is equal to the number of protons in a neutral atom so 35 electrons.
Answer: The entire water/ice solution is at the melting/freezing point, 32°F (0°C). Adding rock salt — or any substance that dissolves in water — disrupts this equilibrium.
Explanation: Hope this helps! Have a great day :)