•common trends and similarities
•similar ions going down (ex: Mg+2 and Ca+2)
•same number of electron orbitals going across
A. It is Basic
for example,
NaOH → Na⁺(aq) + OH⁻(aq)
Ba(OH)₂ → Ba²⁺(aq) + 2OH⁻(aq)
Ca(OH)₂ → Ca²⁺(aq) + 2OH⁻(aq)
pH>7
Answer:
SiH4 is nonpolar and BBr3 is nonpolar and SiF4 is nonpolar.
Explanation:
SiH4 is a non-polar compound. Though the Si–H bonds are polar, as a result of different electronegativities of Si and H. However, as there are 4 electron repulsions around the central Si atom, the polar bonds are arranged symmetrically around the central atom having a tetrahedral shape hence they cancel out making the compound nonpolar.
SiF4 is a nonpolar molecule because the fluorine atoms are arranged symetrically around the central silicon atom in a tetrahedral molecule with all of the regions of negative charge cancelling each other out just like in SiH4.
The 3 bromine atoms all lie in the same plane thus the geometry of the compound will be trigonal planar. The BBr3 will be non polar because the three B-Br bonds will cancel out each others' dipole moment given that they are in the same plane.
Acetonitrile refers to the chemical compound exhibiting the formula CH₃CN. It is the basic organic nitrile and a colorless liquid. It is generated primarily as a byproduct of acrylonitrile production. It is used as a polar aprotic solvent in the purification of butadiene and in organic synthesis.
The addition of water to cyanides generates amines and acids. Acetonitrile produces ammonia and acetic acid.
CH₃CN (acetonitrile) → CH₃COOH (acetic acid) + NH₃ (ammonia)
Answer:
Elements having same valence electrons are placed in <u>same group.</u>
Explanation:
First, let's start with some basic concepts of modern periodic table:
1. Modern Periodic table : It is the arrangement of element in the increasing order of their atomic numbers
The Modern periodic table is divided into Periods and groups .
Periods : These are the horizontal rows. There are seven periods in the periodic table . Period 1 has 2 element. Period two and three has 8 elements , period 4 and 5 have 18 elements and the period 6 and 7 have 32 elements.
Same period have same number of atomic orbital(Shell)
Group : The group is the vertical columns . There are 18 groups in the modern periodic table.Those element which have same group number will also have same number of electron in their outermost shell. The number of electron in the outermost shell determines the valency of the element.
So, elements showing same valency are placed in same group.
All alkali are place in group 1 and have 1 valance electron in the outermost shell
