A condensation reaction is described to be a reaction wherein two molecules form an even larger product and consequently produces a smaller molecule as a by-product. For example, when two amino acids are combined, a dipeptide bond is formed. As a result, 1 molecule of water is produced as a by-product.
Which of these is an isoelectronic series? 1) na+, k+, rb+, cs+ 2) k+, ca2+, or, s2– 3) na+, mg2+, s2–, cl– 4) li, be, b, c 5) n
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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
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
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.
Answer:
Na2CO3 is the formula for sodium carbornate
Answer:
5=C, every action has an equal or opposite reaction,
6=B, since it has less air drag and more force exerted on it
7= You're correct
Answer:
a)


b)
Sulphurdioxide
c)


d)
Incomplete combustion produce harmful gases.
Explanation:
a)
Carbon reacts with atmospheric oxygen to form carbondioxide as well as sulphur dioxide.
The chemical equations are as follows.


b)
Sulfur dioxide is very harmful to the environment to cause acid rains.
This harmful gas mix with rain water to form sulphuric acid.
c)
The balanced chemical equation for the reaction that produces harmful environmental effects is as follows.



d)
In the absence of proper amount of oxygen required for combustion, incomplete combustion will take place which will result in formation of more carbondioxide an other harmful gases.