Answer:
[Kr] 5s²
Explanation:
From the question given above, the following data were obtained:
Atomic number of strontium (Sr) = 38
Electronic configuration =?
Next, we shall determine the electronic configuration of the noble gas element before strontium (Sr).
The noble gas element before strontium (Sr) is krypton (Kr). Thus, the electronic configuration of krypton (Kr) is given below:
Kr (36) => 1s² 2s²2p⁶ 3s²3p⁶ 3d¹⁰ 4s²4p⁶
Finally, we shall determine the electronic configuration of strontium (Sr). This can be obtained as follow:
Kr (36) => 1s² 2s²2p⁶ 3s²3p⁶ 3d¹⁰ 4s²4p⁶
Sr (38) =>?
Sr (38) => 1s² 2s²2p⁶ 3s²3p⁶ 3d¹⁰ 4s²4p⁶ 5s²
But
Kr (36) => 1s² 2s²2p⁶ 3s²3p⁶ 3d¹⁰ 4s²4p⁶
Therefore,
Sr (38) => [Kr] 5s²
C preside over the the Senate
Answer is the mass of the atom. Protons + neutrons= mass
Let's say you have oxygen with a mass of 16.
Oxygen has 8 protons
To find neutrons subtract 16-8= 8
So it would also be 8 neutrons.
Example of how to find mass if you know protons + neutrons:
Sodium has 11 protons and 12 neutrons. Add the protons and neutrons
11 + 12= 23
Mass is 23
Answer:Base A is the weakest conductor electricity
Explanation:
Dissociation is a factor that affects electrical conductivity. The greater the percentage of dissociation for bases the stronger the conductivity of electricity.
Given that
Base A dissociates 25% in water
Base B dissociates 50%.
Base C dissociates 75%
We can conclude that Base A is the weakest conductor oelectricity since it has the lowest percentage of dissociation.