When waves act together, you talk about "interference".
When they reinforce each other, it is "constructive interference".
When they cancel each other, it is "destructive interference".
Magnesium dichloride or Magnesium chloride
Answer:
d and e - Sodium and antimony
Explanation:
The atomic numbers remain the same, while the mass numbers change (because neutrons are being added or taken away).
sodium has an atomic number of 19 and a mass number of 39 - in d, it has an atomic number of 19 but a mass number of 40. therefore, it is an isotope
antimony has an atomic number of 51 and a mass number of 121.60 - in e, it has an atomic number of 51, but a mass number of 123. therefore, it is an isotope
PH is the logarithmic measure of the concentration of hydrogen ions in solution. In an aqueous system, the lowest possible concentration of H+ ions (least acidic) is 1x 10^-14. The -log(1x10^-14) = pH of 14