Answer:
D
Explanation:
Hello!
Since the rate must have the following units: mol/(L*s), the suitable units for k, considering that the term [D] [X] leads to mol^2/(L^2) (it means a second order kinetic law), are L/(mol*s), nevertheless, that answer isn't in the given options.
Answer:-
Alpha decay
Explanation:-
Uranium 238 has atomic number 92 and mass number 238.
Thorium 234 has atomic number 90 and mass number 234.
So, the change in atomic number as uranium 238 disintegrates into thorium234 = 92 – 90 = 2
So, the change in mass number as uranium 238 disintegrates into thorium234= 238 – 234 = 4
We know that when an alpha particle is emitted, the mass number decreases by 4 and the atomic number decreases by 2.
So when an atom of uranium 238 undergoes radioactive decay to form an atom of thorium-234, alpha decay has occurred.
Answer:
Explanation:
An element whose atomic number is 68 (number Z), has 68 electrons and 68 protons. According to the periodic table it corresponds to the element Erbium (Er), whose mass number (A) is 167. The number of neutrons is 167-68 = 99.
Answer:
a. The electronic configuration of the hydride anion is 1s2. TRUE
b. The valence electronic configuration of strontium is 4d2. FALSE
c. For a given value of l the number of possible values of ml is 2l + 1. TRUE
d. Cu+ has the same electronic configuration as Ni. TRUE
e. The magnetic quantum number is never larger than the principle quantum number (for a given orbital). TRUE
Explanation:
a. The electronic configuration of the hydride anion is 1s² is true since the hydriden anion is the hdrogen atom which has gained an electron and we will add that electron to the 1s¹ configuration of H.
b. The valence electronic configuration of strontium is 4d2 is false since Sr is an element of period 5 , therefore its valece electrons are in in period five and it has 2 electrons because Sr belongs to group 2.
c. For a given value of l the number of possible values of ml is 2l+1 is true since this number gives the magnetic orientation for the sublevel. Thus for s there is only one orientation, then ml = 2 (0 ) +1 . Por p with l equal to 1 we have three possible orientations : 2(1) + 1 =3. The d and f sublevels have 10 and 14 orientations.
d. Cu⁺ has the the same electronic configuration as Ni is true since Cu, atomic number 29, has one more electron than its neighbor Ni with an atomic number of 28. If we remove one electron from copper we are gong to have the same 28 electrons niquel has in its neutral state.
e. The magnetic quantum number is never larger than the principal quantum number for a given orbital is true since l, the magnetic quantum number can have values up to n-1, the principal quantum number.
