An isoelectronic series is where all of the ions listed have the same number of electrons in their atoms. When an atom has net charge of zero or neutral, it has equal number of protons and electrons. Hence, it means that the atomic number = no. of protons = no. of electrons. If these atoms become ions, they gain a net charge of + or -. Positive ions are cations. This means that they readily GIVE UP electrons, whereas negative ions (anions) readily ACCEPT electrons. So, to know which of these are isoelectronic, let's establish first the number of electron in a neutral atom from the periodic table:
Na=11; K=19; Rb=37; Cs = 55; Ca=20; S=16; Mg=12; Li=3; Be=4; B=5; C=6, Ar = 18
A. Na⁺: 11-1 = 10 electrons
K⁺: 19 - 1 = 18 electrons
Rb⁺: 37-1 = 36 electrons
B. K⁺: 19 - 1 = 18 electrons
Ca²⁺: 20 - 2 = 18 electrons
Ar: 18 electrons
S²⁻: 16 +2 = 18 electrons
C. Na⁺: 11-1 = 10 electrons
Mg²⁺: 12 - 2 = 10 electrons
S²⁻: 16 +2 = 18 electrons
D. Li=3 electrons
Be=4 electrons
B=5 electrons
C=6 electrons
The answer is letter B.
That force would be gravity. Gravity is what pulls any object down towards Earth due to the large mass of the Earth.
Answer: I believe it's 8
Explanation: The oxygen atom has therefore 8 neutrons, 8 protons and 8 electrons.
Answer:
Option - It would happen faster at warmer air temperatures
Explanation:
The chemical process of converting organic matter such as plants, litter into organic soil, or organic compost called decomposition and perform by decomposers such as fungus or bacteria.
Like all other living organisms, decomposers also live in an optimal range of temperature. The major decomposers normally lie in the range of 30 to 40-degree celsius. Any type of fluctuation in this range might slow down the reaction of decomposition.
Concentration "molarity" of H₂SO₄ in this solution:
5 × 10⁻³ mol / dm³.
<h3>Explanation</h3>
What's the concentration of H⁺ ions in this solution?
![[\text{H}^{+}] = 10^{-\text{pH}}](https://tex.z-dn.net/?f=%5B%5Ctext%7BH%7D%5E%7B%2B%7D%5D%20%3D%2010%5E%7B-%5Ctext%7BpH%7D%7D)
,
where ![[\text{H}^{+}]](https://tex.z-dn.net/?f=%5B%5Ctext%7BH%7D%5E%7B%2B%7D%5D)
is in the unit mol / dm³.
![[\text{H}^{+}] = 10^{-2} \;\text{mol}\cdot\text{dm}^{-3}](https://tex.z-dn.net/?f=%5B%5Ctext%7BH%7D%5E%7B%2B%7D%5D%20%3D%2010%5E%7B-2%7D%20%5C%3B%5Ctext%7Bmol%7D%5Ccdot%5Ctext%7Bdm%7D%5E%7B-3%7D)
.
What's the concentration "molarity" of H₂SO₄ in this solution?
Sulfuric acid H₂SO₄ is a strong acid. Note the subscript "2". Each mole of this acid dissolves in water to produce two moles of H⁺ ions. It takes only 
of H₂SO₄ to produce twice as much H⁺ ions.
As a result, the <em>molarity</em> of H₂SO₄ is 5 × 10⁻³ mol / dm³ or 0.005 M.
