It is called phosphorescent substances.
Answer:
detectives, police officers and occasionaly lawyers/attorneys.
Explanation:
Non essential officers, judges, district attorney investigators, federal agents, victums, witnesses and politics are not permited to enter crime scenes unless they can provide information and history about the event.
Answer: A group 1 alkali metal bonded to fluoride, such as LiF.
Explanation:
Electronegativity is defined as the property of an element to attract a shared pair of electron towards itself. The size of an atom increases as we move down the group because a new shell is added and electron gets added up.
1. A strong acid made of hydrogen and a halogen, such as HCl : A polar covalent bond is defined as the bond which is formed when there is a difference of electronegativities between the atoms. Electronegativity difference = electronegativity of chlorine - electronegativity of hydrogen = 3-2.1= 0.9
2. A group 1 alkali metal bonded to fluoride, such as LiF: Ionic bond is formed when there is complete transfer of electron from a highly electropositive metal to a highly electronegative non metal.
Electronegativity difference = electronegativity of fluorine - electronegativity of lithium= 4-1= 3
3. Carbon bonded to a group 6A (16) nonmetal chalcogen, such as in CO: A polar covalent bond is defined as the bond which is formed when there is a difference of electronegativities between the atoms.
Electronegativity difference = electronegativity of oxygen - electronegativity of carbon= 3.5-2.5= 1.0
4. A diatomic gas, such as nitrogen
: Non-polar covalent bond is defined as the bond which is formed when there is no difference of electronegativities between the atoms.
Electronegativity difference = 0
Thus the greatest electronegativity difference between the bonded atoms is in LiF.
All acids only conduct electric current when they are dissolved in water, because when they are in an aqueous medium, they undergo ionization, i.e. release <span>ions.</span><span>
HCl --> H</span>⁺ + Cl⁻
The bases also conduct electric current in solution, because the Ionic dissociation sufferers (release the existing ions in the formula) and molecular ionization, suffer the reacting with water and releasing ions.
NaOH ---> Na⁺ + OH⁻
hope this helps!
A better explanation of these systems is given using molecular orbital theory.
<h3>What is the valence bond theory?</h3>
The valence bond theory hold that a bond is formed by the sharing of two electron in a covalent bond. This bond does not account for certain systems that occur in multiple bonded systems where the simple two electron bonding model does not suffice.
Thus, valence bond theory is inadequate for describing systems with multiple adjacent bonds that overlap, as in aromatic molecules. a better explanation of these systems is given using molecular orbital theory.
Learn more about valence bond theory:brainly.com/question/23129240
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