Answer:
Explanation:
(a) Firstly, caesium abd potassium are both in Group 1 of the periodic table. Group 1 metals (also called alkali metals) are the most reactive metals of the periodic table. Caesium is more reactive than Potassium because it has a higher electropositivity than Potassium. Electropositivity is the tendency of a metal to donate electron(s) to form a cation. Electropositivity increases down the group; this is because it is easier for atoms to loose electrons on the outermost shell that are far away from the central nucleus as against atoms whose outermost electrons are closer to the central nucleus. <u>Thus, the more "bulky" an atom is, the farther it's outermost electrons (valence electrons) get from the central nucleus and the easier it is to lose the outermost electron(s). And the easier it is for the valence electron(s) to be removed, the more reactive the atom would be and vice-versa.</u>
Caesium is more reactive than potassium because it is more bulky than potassium, with an atomic number of 55, while potassium has an atomic number of 19.
NOTE: The closer an electron is to the nucleus, the more difficult it is to be removed from it's shell.
(b) i. Formula for Caesium Nitrate:
Symbol for Caesium is Cs and Nitrate is NO₃⁻.
Cs⁺ + NO₃⁻ ↔ CsNO₃
Formula for Caesium Nitrate is CsNO₃
ii. Formula for Caesium sulphate
Symbol for caesium is Cs and Sulphate is SO₄²⁻
Cs⁺ + SO₄²⁻ ↔ Cs₂SO₄
Formula for Caesium sulphate is Cs₂SO₄
NOTE: When writing the formulae, the charges would be exchanged to form the subscript as seen on the product sides above.
Longitudinal. (just remember that Transverse waves are perpendicular. T is like an inverted perpendicular sign)
Answer:
Sc (Scandium) has the given electronic configuration.
Explanation:
The given electronic configuration is [Ar]
.
The last electron enters the d-subshell and hence is a d-block element known as Scandium with chemical symbol Sc.
For 4s subshell
n=4,l=0 and m ranges from -l to +l so m=0.
For 3d subshell
n=3,l=2 and m ranges from -l to +l so m can take values -2,-1,0,+1,+2
Note:
l values for subshells:
s : 0
p : 1
d : 2
f : 3 and so on.
Answer:
Pre-zygotic, temporal separation
Explanation:
Reproductive isolation mechanism is of two types:
- Prezygotic mechanism
- Postzygotic mechanism
Prezygotic mechanism isolation occurs before fertilization and helpful in preventing formation of fertile offspring.
In frog external fertilization occurs. In the external fertilization, eggs and sperms are released in water and fertilization occur outside the water.
Prezygotic isolating mechanisms may include behavioral isolation, temporal isolation, mechanical isolation, gametic isolation and habitat isolation.
Temporal separation in reproduction is the sexual activity in the same geographical range but in different periods.
Therefore, the given reproductive isolation is pre-zygotic, temporal separation.
It forms <span>calcium phosphate and potassium nitrate
</span>2 K3PO4 + 3Ca(NO3)2 --> Ca3(PO4)2 + 6KNO3
