Electrons in an atom can be classified as core electrons and valence electrons. Valence electrons are those electrons which are present in valence shell and participates in bond formation. While, Core electrons are all remaining electrons which are not present in valence shell, hence not take part in bonding.
Atomic number of Selenium (Se) is 34 hence it has 34 electrons with following electronic configuration;
1s², 2s², 2p⁶, 3s², 3p⁶, 4s², 3d¹⁰, 4p⁴
From electronic configuration it is found that the valence shell is 4, and the number of electrons present in valence shell are 6. So,
Core Electrons = Total Electrons - Valence Electrons
Core Electrons = 34 - 6
Core Electrons = 28
Result:
There are 28 core electrons in Selenium.
Answer:
0.6257 M is the molarity of solution that is 5.50 percentage by mass oxalic acid.
Explanation:
Mass percentage of oxalic acid = 5.50%
This means that in 100 grams of solution there are 5.50 grams of oxalic acid.
Mass of solution , m = 100
Volume of the solution = V
Density of the solution = d = 1.024 g/mL
V = 97.66 mL = 0.09766 L
(1 mL = 0.001 L)
Moles of oxalic acid = 
The molarity of the solution :
0.6257 M is the molarity of solution that is 5.50 percentage by mass oxalic acid.
In an ionic bond, one atom essentially donate an electron to stabilize the other atom. A molecule bond is made when two or more atoms form a chemical bond, linking them together. The two types of bonds are ionic bonds and covalent bonds.
Answer:
The sequence order should be DNA to RNA to Proteins.
Explanation:
For you to get the RNA sequence, you need to find a match for the DNA sequence. Your RNA sequence should only have either AUCG for your 4 nucleotide bases. Once you have the RNA sequence found by pairing it with the DNA sequence, you would then to do use an RNA codon chart to find the amino acids. These amino acids are basically your proteins.
