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2024 Questions And Answers
The mole concept - correct answer A method that allows the relative number of reactant particles involved in a chemical reaction to be known Avogadro's number - correct answer number of representative particles in a mole, 6.02 X 10^ Basic structures of atoms - correct answer There is a nucleus in the center surrounded by an electron cloud or field Quantum numbers - correct answer Quantum numbers describe values of conserved quantities in the dynamics of a quantum system. In the case of electrons, the quantum numbers can be defined as "the sets of numerical values which give acceptable solutions to the Schrödinger wave equation for the hydrogen atom" Common compounds - correct answer Water (H2O), table salt (NaCL); carbon dioxide (CO2); baking soda (NaHCO3); carbon monoxide (CO); sand or glass (SiO2)
2024 Questions And Answers
Periodic properties - correct answer chemical or physical properties that vary among elements according to trends that repeat as atomic number increases What are the periodic properties? - correct answer Element (on periodic table) - correct answer Atomic number is the same as - correct answer number of protons Atomic mass is the same as - correct answer Number of protons and neutrons Different types of chemical bonding - correct answer metallic, covalent, ionic What is covalent bonding and how does it work? - correct answer when atoms share one or more pairs of electrons. They have similar electronegativities
2024 Questions And Answers
Substances with hydrogen bonding have higher melting and boiling points because of the extra energy needed to break the hydrogen bonds. What is a dipole-dipole force? - correct answer The attraction between the positive end of one polar molecule and the negative end of another What is a london dispersion force? - correct answer weak forces that result from temporary shifts in the density of electrons in electron clouds What is the lewis structure? - correct answer diagrams that show the bonding between atoms of a molecule and the lone pairs of electrons that may exist in the molecule. Geometry of molecules - correct answer The number of atomic orbitals used to create a set of hybrid orbitals equals the number of orbitals generated by hybridization. Lewis structure of Ozone - correct answer bent
2024 Questions And Answers
Lewis structure of CO2 - correct answer linear Lewis structure of H2O - correct answer bent Lewis structure of Methane - correct answer tetrahedral structure Lewis structure of ammonia - correct answer trigonal pyramidal Lewis structure Ethene - correct answer Lewis structure Ethane - correct answer Lewis Structure methanol - correct answer Lewis Structure propanol - correct answer
2024 Questions And Answers
system at equilibrium, the system shifts in the direction that relieves the stress. Chemical equilibrium example - correct answer H₂ (g) + I₂ (g) ⇌ 2HI (g) at any given time, H₂ & I₂ are combing while 2HI is breaking down - all three chemicals will be present. Pressure increase equilibrium shift - correct answer then the equilibrium shifts to the side with the fewer number of moles of gas Increasing temperature equilibrium shift - correct answer endothermic - shifts right exothermic - shifts left concentration shift equilibrium - correct answer If we add additional product to a system, the equilibrium will shift to the left, in order to produce more reactants. Or, if we remove reactants from the system, equilibrium will also be shifted to the left. Brownsted-Lowry theory - correct answer Acid is a proton donor Base is a proton acceptor
2024 Questions And Answers
Lewis theory - correct answer An acid is an electron pair acceptor and a base is an electron pair donor pH formula - correct answer pH=-log[H+] pH definition - correct answer measure of hydrogen ion concentration Strong acids - correct answer HCl, HBr, HI, HNO3, H2SO4, HClO Weak acids - correct answer H2SO3, HNO2, HF, HCO2H, H3PO Weak base examples - correct answer NH₃, H₂O, F⁻, CN⁻, CH₃COO⁻ Strong base examples - correct answer LiOH, NaOH, KOH, RbOH, CsOH, Ca(OH)2, Sr(OH)2, Ba(OH)
2024 Questions And Answers
nitrogen compounds - correct answer ammonia, hydrogen cyanide, cyanogen, and nitrous or nitric acid phosphorus compounds - correct answer derivatives of phosphate (PO43−), a tetrahedral anion. Phosphorus pentoxide (P4O10) is the acid anhydride of phosphoric acid, but several intermediates between the two are known. This waxy white solid reacts vigorously with water sulfur compounds - correct answer pyrite (iron sulfide), cinnabar (mercury sulfide), galena (lead sulfide), sphalerite (zinc sulfide), and stibnite (antimony sulfide) Types of organic chemical reactions - correct answer Organic reactions are chemical reactions involving organic compounds. The basic organic chemistry reaction types are addition reactions, elimination reactions and substitution reactions Functional groups - correct answer A specific configuration of atoms commonly attached to the carbon skeletons of organic molecules and involved in chemical reactions.
2024 Questions And Answers
What is an isomer? - correct answer Compound with same atoms, but arranged differently Examples of isomers - correct answer glucose and fructose structural isomers - correct answer Differ in arrangement of atoms. isomer example - Functional group alkanes - correct answer C-C single bond Functional group alkenes - correct answer C=C double bond Functional group alkynes - correct answer C=C triple bond Nomenclature alkanes - correct answer -ane
2024 Questions And Answers
- melting points lower than alkanes with same # of C's Chemical properties alkynes - correct answer - boiling and melting point increases as their molecular structure grows bigger
- acidic nature physical properties alkynes - correct answer - odorless and colorless
- exist in all three states
- slightly polar in nature Aromatic hydrocarbons - correct answer hydrocarbons that contain a ring structure similar to benzene examples of aromatic hydrocarbons - correct answer benzene and toluene Alcohol classification - correct answer by number of alkyl groups attached to carbon bonded to hydroxyl
- Primary (1º)
2024 Questions And Answers
- Secondary (2º)
- Tertiary (3º) physical properties of alcohols - correct answer - very polar
- H-bonding ability
- high boiling points chemical properties of alcohols - correct answer - combustion
- Alcohols can be reacted with carboxylic acid to form esters Nomenclature ether - correct answer -oxy Nomenclature phenyl (confusing one) - correct answer benzene ring therefore benzene Oxo compounds - correct answer Oxo compounds are organic compounds that contain the karbonyl group, C=O. The term thus embraces aldehydes, carboxylic acids, ketones, amides, and esters.
2024 Questions And Answers
Nomenclature ester - correct answer -oate nomenclature amide - correct answer -amide functional group amide - correct answer -CONH functional group amine - correct answer NH nomenclature amine - correct answer -amine amine classification - correct answer classified as primary (1°), secondary (2°), or tertiary (3°), depending on how many carbon groups are connected to the nitrogen atom the peptide bond - correct answer covalent bond formed between amino acids
2024 Questions And Answers
amino acid example - correct answer Isoeucine, Leu Components of nucleic acids - correct answer - Sugar -- Deoxyribose in DNA -- Ribose in RNA
