Chemical bonding explanation
A chemical bond describes an attractive interaction that holds atoms or ions together in a chemical structure. Introductory categories…
Blog
Articles, guides, and pillar pages across our topic clusters.
Where are the valence electrons of an atom found
In the usual main-group model, valence electrons occupy an atom’s outermost occupied principal shell. They are important in bonding an…
What is rh factor in chromatography
In introductory thin-layer or paper chromatography, Rf usually means retention factor. RH factor is a different term in other contexts…
Pka of an acid
pKa is the negative base-ten logarithm of an acid dissociation constant: pKa = −log₁₀Ka. Under comparable conditions, a lower pKa corr…
Is sour taste a chemical or physical property
Taste is commonly classified as a physical property because describing the sensation does not, by itself, define a substance’s capacit…
Atomic weight al
Al is the chemical symbol for aluminum, also called aluminium. Its standard atomic-weight value is about 26.98 in many introductory ta…
Molecular weight of sodium
Sodium is represented by Na and has a commonly used atomic-weight value of about 22.99. Its molar mass is correspondingly about 22.99…
Size periodic table trend
Atomic radius generally decreases across a period and increases down a group. These trends reflect changes in nuclear attraction, shie…
Molecular shape of sf4
SF₄ has a seesaw molecular shape in the standard VSEPR description. Sulfur has four bonding domains and one lone pair, for five electr…
Molecular geometry for nh3
Ammonia, NH₃, has trigonal pyramidal molecular geometry in the usual VSEPR model. Nitrogen has three bonding domains and one lone pair…
Homogenous and heterogeneous mixtures
A homogeneous mixture has a uniform composition at the scale being considered, while a heterogeneous mixture has distinguishable regio…
Electron domain geometry of hcn
In the standard Lewis structure H–C≡N, carbon is the central atom. It has two bonding electron domains and no lone pairs, giving linea…
