EverythingOnConstruction - Ask. Build. Learn together. Logo

Questions in chemistry

[Solved] Each atom of an element has the following electron configuration: [tex]$1 s^2 2 s^2 2 p^6 3 s^2 3 p^6 4 s^2 3 d^{10} 4 p^6 5 s^2 4 d^{10} 5 p^5$[/tex] What is the name of the element? A. bromine B. iodine C. tellurium D. xenon

[Solved] 109. Identify the set of reagents that can effect bromination in benzene. (a) Bromine/Hydrogen bromide (b) Bromine/FeBr₃/H₂O (c) Bromine/FeBr₃ (d) Bromine/FeBr₂ 110. What is the reagent R in the reaction below? COCl | \ R -> CHO / (a) LiAlH₄ (b) LiAlH[O(CH₃)₃]₃ (c) NaBH₄ (d) H₂/Ni 111. Carboxylic acids have higher melting points compared to alcohols with the same number of carbon atoms because: (a) acids exhibit hydrogen bonding (b) acids have higher molecular weight (c) alcohols have polar character (d) alcohols usually occur as dimers 112. Identify Q in the reaction represented by the equation below: CONH₂ | \ Q -> NH₂ / (a) LiAlH₄ (b) KBr (c) KMnO₄ (d) NaNH₂ 113. Which of the following pairs of compounds will exhibit isomerism? (a) C₄H₁₀ and C₂H₅O (b) C₄H₁₀ and C₂H₆O (c) C₄H₁₀ and C₂H₅O₂ (d) C₄H₁₀ and C₆H₁₂ 114. An ester will not be formed when an alcohol is reacted with: (a) a carboxylic acid (b) an aldehyde (c) an acid anhydride (d) an acid chloride 115. Esters generally have lower boiling points than their corresponding carboxylic acids because: (a) they are volatile (b) they are associated (c) they are not associated (d) are non-volatile 116. Which of the following statement(s) is/are true of esters? (a) they are colourless liquids (b) they have a pleasant fruity odour (c) they are used for flavouring (d) all of the above 117. The reduction of esters to alcohols can be brought about by: (a) LiAlH₄/C₂H₅OH (b) LiAlH₄/(C₂H₅)₂O (c) NaBH₄/(C₂H₅)₂O (d) NaBH₄/C₂H₅OH

[Solved] Which will not appear in the equilibrium constant expression for the reaction below? [tex]H_2 O(g)+C(s) \longleftrightarrow H_2(g)+CO(g)[/tex] A. [C] B. [tex][H _2][/tex]

[Solved] How four atoms, labeled $W, X, Y$, and $Z$, can combine with each other to form Which combination of atoms will not form a compound? W and X X and Y W and Z Y and Z

[Solved] The equation below represents a reaction that takes place in an industrial process. [tex]4NH_3 + 5O_2 \rightarrow 6H_2O + 4NO[/tex] a. Name the catalyst used. b. What are the other conditions for the reaction? c. Why are the products cooled before being oxidized?

[Solved] Select the correct answer. Which statement correctly relates two substances from this reaction? [tex]H_2 CO_3+H_2 O \rightleftharpoons H_3 O^{+}+HCO_3^{-}[/tex] A. [tex]HCO _3{ }^{-}[/tex] is the conjugate acid of [tex]H _2 CO _3[/tex]. B. [tex]H _2 O[/tex] is the conjugate base of [tex]H _2 CO _3[/tex]. C. [tex]H _3 O ^{+}[/tex] is the conjugate acid of [tex]H _2 O[/tex]. D. [tex]H _2 CO _3[/tex] is the conjugate base of [tex]H _3 O ^{+}[/tex].

[Solved] A low-spin octahedral complex of Fe²⁺ with strong-field ligands will have VBT hybridization: A) sp³d² B) dsp² C) d²sp³ D) sp³

[Solved] Chemical erasures of words or numbers may be revealed by examination of handwriting under A. x-ray fluorescence B. gamma radiation C. infrared light D. visible light

[Solved] (b) (i) State a reason for each of the following: I. The lid of a desiccator should be made air-tight by greasing. II. The milkiness of lime water disappears when excess carbon (IV) oxide is passed into it. (ii) Write a chemical equation for (b)(i) II. (iii) Name two gases that can be used for the fountain experiment.

[Solved] Give the IUPAC nomenclature of the following: I. [tex]CH _3( CH _2)_5 CHC ( CH _3) C ( CH _3)_3[/tex] II. Ethyl methaneate Trans - 2,3-dimethyl had - 2 ene III. [tex]Cl ( CH _3)_2 CH _2 CHCHCHCCl ) CH _3[/tex]