The metal is lead, Pb.
One unit of the oxide contains one atom of O (16.00 u).
∴ Mass of oxide = 16.00 u O × (100 u MO/7.17 u O) = 223.15 u MO
Mass of M = mass of MO – mass of O = 223.15 u -16.00 u = 207.2 u
The only element with an atomic mass of 207.2 u is lead (Pb) and the formula of the oxide is PbO.
Atom is the smallest indivisible particle of matter.
For radioactive decay, we can relate current amount, initial amount, decay constant and time using:
N = No x exp(-λt)
Half-life = ln(2)/λ
λ = ln(2) / 5730
N/No = 80% = 0.8
0.8 = exp( -ln(2)/5730 x t)
t = 1844 years
They don't change what the substance really is unlike chemical change. They chemical formula of the substance stays the same even though the substance can go under shape change.
<h3><u>Answer;</u></h3>
D. It decreases and the pH increases.
<h3><u>Explanation;</u></h3>
- pH is a measure of the hydorgen ion concentration of a solution. Solutions with a high concentration of hydrogen ions have a low pH and solutions with a low concentrations of H+ ions have a high pH.
- <em><u>[H+] and [OH-] are inversely related. Therefore; As the concentration of H+ increases the pH decreases. Since the concentrations of H+ and OH- are inversely proportional, as one goes up, the other goes down. </u></em>
- <em><u>Therefore, an increase in OH- concentration will correspond to an increase in pH and a decrease in the concentration of H+.</u></em>
