Answer: 19
Explanation:
In order to write the Potassium electron configuration we first need to know the number of electrons for the K atom (there are 19 electrons). When we write the configuration we'll put all 19 electrons in orbitals around the nucleus of the Potassium atom.
Basically, the arrangement of electrons in electronic configuration follows three principles:
1. Aufbau Principle
You start from the highest energy level to the lowest. The arrangement is: <span>1s<2s<2p<3s<3p<4s<3d<4p<5s<4d<5p<6s<4f<5d<6p<7s<5f<6d<7p.
2. Hund's Rule
Each box in the configuration can hold up to 2 electrons. This rule tells you to fill all boxes of one particular subshell with 1 electron first, before double occupying them.
3. Pauli's Exclusion Principle
This rule tells you that the two electrons in a box shall always have opposite spins, represented by one half-arrow up and one half-arrow down.</span>
Nearby stars are measured with parallax, which involves two measurements of the star's exact position in the sky.
Hope this helped!
Good luck :p
Brainliest is appreciated <3
~ Emmy
Answer:
a. The formula for tritoborate ion is B₃O₈²⁻
b. The formula of the compound formed will be Fe₂(B₃O₈)₃ and the name will be Iron (iii) tritoborate
Explanation:
The formation of compounds by atoms of elements occurs in accordance with the valencies of the elements. Valency refers to the combining power of an element. For metallic elements, it is usually the number of electrons they can give up or lose while for non-metallic elements, it is the number of electrons they can accept. The valency of an atom of an element is related to its oxidation number. Metals have positive oxidation numbers while non-metals have negative oxidation numbers. Sometimes, two or more atoms combine together and react as a single unit and may carry a positive or negative charge. These are known as a radicals. For example, ammonium ion, NH₄⁺.
In the given question, calcium tritoborate, CaB₃O₈ is formed from the combination of calcium ion and tritoborate ion. Calcium ion carries the charge of +2, therefore, the tritoborate ion must have a charge of -2 in order to form a compound since the overal charge on a compound is zero.
a. let the tritoborate ion be represented by X
Ca = +2, X = ?
+2 + X = 0
X = -2
Thus, the formula for tritoborate ion is B₃O₈²⁻
b. When tritoborate ion combines with iron (iii) ion, Fe³⁺, two moles of Fe³⁺ will be required to react with three moles of B₃O₈²⁻ in order to have a neutral compound. The formula of the compound formed will be: Fe₂(B₃O₈)₃ and the name will be Iron (iii) tritoborate
