The total number of electrons in the outermost principal energy level of an element is called its —
- aproton number
- batomic mass
- cvalence electrons
- dcore electrons
220 questions · 15 sections
The total number of electrons in the outermost principal energy level of an element is called its —
Potassium (K, Z=19) has how many valence electrons?
Oxygen (Z=8) has how many valence electrons?
Nitrogen (N, Z=7) has valence electrons —
Fluorine (F, Z=9) has valence electrons —
Phosphorus (P, Z=15) has valence electrons —
Chlorine (Cl, Z=17) has valence electrons —
Calcium (Ca, Z=20) has valence electrons —
Which orbit is the outermost for nitrogen?
For potassium (), which is the outermost orbit?
Number of electrons in the K orbit of phosphorus is —
The valence electron count is taken from which orbit?
The bonding capacity of an atom with another atom while forming a molecule is called —
Valency of hydrogen is conventionally taken as —
Valency of an element is determined by the number of which atoms can bond with one of its atoms?
Valency of chlorine in HCl is —
Valency of oxygen in is —
Valency of Na in NaCl is —
To determine valency from oxygen, multiply the number of bonded O atoms by —
Valency of Ca derived from CaO is —
Valency of magnesium is —
Valency of aluminum is —
Valency of zinc is —
Valency of silver in AgCl is —
An element having more than one valency shows —
Variable valencies of iron (Fe) are —
Variable valencies of copper (Cu) are —
Variable valencies of carbon (C) are —
Variable valencies of lead (Pb) are —
Valencies of nitrogen (N) listed in the chapter are —
Valencies of sulfur (S) listed in the chapter include —
The difference between the highest valency and the active valency of an element is called —
In , active valency of Fe is 2 and highest is 3, so latent valency is —
In , latent valency of Fe is —
In , the active valency of P is —
A charged cluster of atoms acting as a single ion is called —
The valency of a radical equals —
Charge on the ammonium ion () is —
Valency of the ammonium radical is —
Charge on the carbonate ion () is —
Valency of the carbonate radical is —
Valency of hydrogen carbonate () is —
Charge on the sulfate ion () is —
Valency of hydrogen sulfate () is —
Valency of sulfite () is —
Valency of nitrate () is —
Valency of nitrite () is —
Valency of phosphate () is —
Valency of hydroxide () is —
Valency of phosphonium () is —
The numbers of atoms or radicals in a molecule are written in the formula as —
Chemical formula of nitrogen molecule is —
Chemical formula of ozone is —
Iron is written as —
Helium is expressed as —
Valency of Al = 3 and O = 2; the formula of aluminum oxide is —
Formula of calcium chloride (Ca = 2, Cl = 1) is —
Formula of magnesium phosphate (Mg = 2, = 3) is —
Formula of ammonium phosphate is —
Formula of aluminum sulfate is —
When valencies share a common factor, divide by it; for C (4) and O (2), the formula becomes —
Formula of ferrous sulfate (Fe = 2, = 2) is —
Formula of boron nitride (B = 3, N = 3) is —
When a radical appears more than once in a formula, it is enclosed in —
Formula of magnesium chloride is —
In the compound , the active valency of Fe is —
The formula expressing the symbols and numbers of constituent atoms is the —
The formula expressing organization and bonds of atoms is the —
Molecular formula of propane is —
In propane, each carbon's valency is satisfied to —
In a structural formula, a bond is represented by —
Structural formula of methane shows central C bonded to —
In water's structural formula, two H atoms bond to —
Each line between C–C or C–H in represents a —
Molecular formula of methane is —
Total number of atoms in one molecule is —
All inert gases other than helium have how many electrons in the outermost shell?
The rule that elements attain 8 electrons in the outermost shell to gain inert-gas configuration is the —
In , the central C atom has how many outermost-shell electrons after bonding?
The newer, more universal rule extending the octet idea is the —
According to the duet rule, an atom in a molecule has, at the outermost level —
In , the central Be atom has how many electron pairs at its outermost level?
In , the central B atom has how many electron pairs at its outermost level?
In , the central C atom has how many electron pairs at its outermost level?
In , the H atom has how many electron pair(s) at its outermost shell?
In , each F atom has how many electron pairs at its outermost shell?
The octet/duet rules are mainly applicable to elements with atomic numbers —
Helium's stability comes from having outermost electrons —
In , the four electrons paired with C come from —
The duet rule states an atom holds outermost electrons in —
Inert gases belong to which group of the periodic table?
Helium's electronic configuration is —
Neon's electronic configuration is —
Argon's electronic configuration is —
Inert gases are stable because their outermost shell is —
Inert gases —
The fulfilled-outer-shell configuration that drives bond formation in other elements is the configuration of —
Number of valence electrons in radon (Rn) is —
Why do non-inert elements form bonds?
Inert gases are also called —
The attractive force that keeps atoms together in a molecule is called —
In , the bond is between —
In HCl, the chemical bond is formed between —
The basic reason behind chemical bonding is —
Atoms achieve inert-gas configuration by —
Without chemical bonds, atoms in a molecule would —
Chemical bond formation generally —
Two atoms form a bond when they —
In a neutral atom, the number of protons equals the number of —
An atom that loses one or more electrons becomes a —
An atom that gains one or more electrons becomes a —
Lithium loses an electron to become —
The configuration that attains matches that of —
Sodium loses an electron to attain the configuration of —
Metals are usually located on which side of the periodic table?
The outermost shell of metals usually has electrons numbering —
Metals have low ionization energy because —
Non-metals are located on which side of the periodic table?
Non-metals usually have outermost electrons numbering —
Non-metals tend to —
Cl gains one electron and becomes —
attains the configuration of —
Why do non-metals not generally form cations?
The tendency to accept electrons is called —
The bond formed by transfer of electrons from a metal to a non-metal is —
Ionic bond is also known as —
The force holding cations and anions together in an ionic compound is —
In NaCl, Na transfers how many electron(s) to Cl?
In MgO, Mg donates how many electrons?
The ion has the configuration of —
In CaO, Ca donates how many electrons?
In NaH, the hydrogen exists as —
in NaH has electrons in its outermost shell numbering —
Ionic bonds are usually formed between metals of groups —
Non-metals typically forming ionic bonds belong to groups —
The exception group-13 metal that forms ionic bonds is —
Compounds containing an ionic bond are called —
The strength of an ionic bond is —
Which of the following is an ionic compound?
Charge on in MgO is —
In CaO, after bonding the Ca ion has charge —
The number of electrons in the outermost shell of is —
Ionic compounds are organized in three-dimensional arrangements called —
Why are ionic compounds usually solid at room temperature?
The bond formed by sharing electron pairs between non-metals is —
In , each Cl shares how many electron(s)?
Total electrons participating in one covalent bond —
A covalent bond is denoted by —
Number of covalent bonds in an molecule is —
In , the configuration each H attains matches that of —
In an molecule each O atom shares how many electrons?
Number of covalent bonds in —
In , how many lone (non-bonding) electron pairs remain on the O atom?
Sulfur exists as a covalent molecule in the form —
Phosphorus exists as a covalent molecule in the form —
Which of the following is NOT a covalent compound listed in the chapter?
Which compound has covalent bonds only?
Weak attraction forces between covalent molecules are —
Why are most covalent compounds easily separable from each other?
Which covalent compound is liquid at NTP?
Which covalent molecule is solid at NTP?
Vander Waals force is hardly effective on —
Which atom can form both ionic and covalent bonds (per chapter)?
The Na atom can —
Melting points of ionic compounds compared to covalent ones are generally —
Boiling points of ionic compounds are generally —
Why are ionic compounds' melting points high?
Inter-molecular force in covalent compounds is mainly —
Which is more soluble in water?
Which covalent compound is water-soluble (per chapter)?
Most ionic compounds are —
Reason ionic compounds dissolve in water —
Water acts as what kind of solvent?
In a water molecule, oxygen carries a partial —
In a water molecule, hydrogen carries a partial —
The electron pair shifts toward oxygen in water because oxygen is —
The symbol used for partial positive charge is —
The symbol used for partial negative charge is —
A covalent compound with partial charges is called —
Which is a polar covalent compound listed in the chapter?
Which water solution conducts electricity?
Why does sugar solution NOT conduct electricity?
In NaCl solution, the carriers of electric current are —
Which compound does NOT conduct electricity in solution?
Crystals form most readily from —
A covalent compound that can also crystallize is —
Which substance dissolves in water due to its polarity, although covalent?
Electronegativity is —
The bond holding atoms in a piece of metal is the —
The outermost shell electrons of metals usually number —
Atoms in a metal lose outermost electrons to form —
The free, mobile electrons in a metal are called —
Atomic cores in a metal are arranged in —
The metallic bond results from attraction between atomic cores and —
Which property of metals is due to delocalized electrons?
Heat conductivity of metals is due to —
When current flows in a metal, electrons travel from —
Without delocalized electrons, a metal would —
Heat moves through a metal because heated electrons —
The bright luster of metals is attributed to —
Flexibility / malleability of metals comes from —
Identify a metallic bond example:
Atomic cores in a metal carry which charge?
Conductivity of metals (compared to ionic compounds in solid state) is —
A locally available object identified as an ionic compound by the water-solubility test —
Which is a covalent compound (insoluble in water)?
Which compound has Vander Waals forces between its molecules?
The formation of which molecule below attains the electron configuration of neon?
Which of the following compounds is water-soluble?
Which of the following is NOT electro-conductive in water solution?
Why does methane not dissolve in water?
follows the octet rule because the central C has —
Why does molten NaCl conduct electricity?
Which one is NOT a property of covalent compounds in general?
Which is true for covalent compounds in solid state (per chapter)?
Why is HCl conductive in water?
Group-1 alkali metals form which type of bond with halogens?
The structural formula of a compound shows —
Why are F's valency and valence electrons not the same?
Two non-metal atoms form which type of bond?