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.
The balanced chemical reaction is:
N2 + 3H2 = 2NH3
We are given the amount of ammonia formed
from the reaction. This is where we start our calculations.
0.575 g NH3 (1 mol NH3 / 17.03 g NH3) (3 mol
H2 / 2 mol NH3) ( 2.02 g H2 / 1 mol H2) = 0.10 g H2
Answer:
Single displacement reaction
Explanation:
2AI + 6HCI —> 2AlCl3 + 3H2
From the above reaction, we see clearly that Al displaces H from HCl. This is clearly a single displacement reaction.
Answer: This is only a guess: The "following chemical formula: " doesn't appear on my screen. But since you mentioned Mg and Cl, I would guess MgCl2
Explanation: Mr loses 2 electrons while each Cl gains one each: Two chlorines for every 1 magnesium.
An atom becomes positively charged by loosing electrons.
