Why do elements always have ΔH∘f=0? a) The standard state of elements is the reference point for measuring of enthalpy changes. b) ΔH∘ reflects the complexity of compounds. c) Elements do not have heteroatomic bonds and these bonds cause enthalpy changes. d) The internal energy of elements is zero.

Q: The pOH of an aqueous solution of 0.392 M hydrocyanic acid, (K₁ (HCN) = 4.0 × 10-10) is

A: In this question we have to find the pOH of an aqueous solution  Given that  C= 0.392 M  Ka = 4 ×…

Q: Aspartame, the artificial sweetener in NutraSweet and Equal, contains 57.14% carbon, 6.16% hydrogen,…

A:

Q: Br ОН CH₂Br IV NaCN 0 NH₂ II H2O/H ? ОН III ОН

A:

Q: 5. Calculate the change in energy required to convert 250. g of substance X from a gas at 121.00°C…

A: Answer: Energy change for the mentioned process will occur in 5 steps: 1. Cooling of gas up to its…

Q: Draw the product of the reaction shown below. Ignore inorganic byproducts. NaOCI HOAC OH

A: “Since you have asked multiple questions, we will solve the first question for you. If you want any…

Q: 3. Consider the following pairs of compounds. (CLA) a. Br₂ and 12- Pick the one with the higher…

A: We are given a pair of compounds in the question. We need to identify the one with higher vapour…

Q: a. For the following unbalanced equation, calculate how many moles of the second reactant would be…

A: The balanced chemical reaction of cobalt and fluorine is as follows: 2Cos + 3F2g  →  2CoF3g The…

Q: How many electrons will the following elements gain or lose when they form ions? Use the dropdown on…

A: All elements are try to get stable electronic configuration as noble gas or complete it's octet.…

Q: If a particular liquid has a normal boiling point of 338.0 K and a vapor pressure of 75.0 mmHg at…

A: Given, Note: vapour pressure at normal boiling point = 1 atm Vapour pressure (P): P1 = 1 atm = 760.0…

Q: Natural waters often contain relatively high levels of calcium ion, Ca²+, and hydrogen carbonate ion…

A:

Q: Which statements about vapor pressure below are true? Select all that apply. A. Water in a 150 mL…

A: Vapour pressure is a measure of the tendency of a material to change into the gaseous or vapour…

Q: Trichloroethylene, C2HCl3 is used as a dry cleaning solvent and an industrial extraction agent. The…

A: According to the question, The mass of the trichloroethylene should be = 5.0 ppb The volume of water…

Q: Draw the structure(s) of the major organic product(s) of the following reaction. aqueous HCI

A:

Q: Calculate the volume in liters of a 0.053 mol/L potassium dichromate solution that contains 75.0 g…

A: In this question, we will determine the volume of the solution in L unit.  Given that,  Molarity of…

Q: Figure I-1 I p 小 +++ 工 N=C, 木木 印女子 ③ H 1 H 工 ++ p++ IV H 味 p #北子 V ++++

A: We have find out the solution.

Q: On an archeological dig, a wooden canoe is unearthed and analyzed for carbon-14. About 25% of the…

A: Radioactive decay follows first-order kinetics. The half-life of the first-order reaction does not…

Q: 1. Based on your observed line wavelength in your data table, calculate 1/A (m-¹) and n, then…

A: Solutions- Here we are given wavelength values and we have to find ni for different wavelength.

Q: Identify the following elements with their corresponding mass number. Use this format for your…

A: We have find out the solution.

Q: 14. Bromine is often used as a laboratory spot test for unsaturation in an aliphatic hydrocarbon.…

A: The molecular formula of the given compound is C6H6  Vial A decolorize Bromine and Vial B did not…

Q: A gas was found to have a pressure of 714.9 torr. What is the pressure in atm? Selected Answer:…

A:

Q: 7. Which of the following structures have incorrect IUPAC names? If incorrect give the correct one.…

A: We know priority order follow : Functional group > double bond > tripple bond > substituent…

Q: 19. Equal volumes of what concentrations of AgNO3 and HCI should be mixed to form a AgCl…

A: For the precipitation of an electrolyte, it is necessary that the ionic product must exceed its…

Q: For a particular isomer of Cg H₁g, the combustion reaction produces 5093.7 kJ of heat per mole of Cg…

A: Answer: When a hydrocarbon is burned in presence of oxygen its combustion causes a release of energy…

Q: Liquid hexane will react with gaseous oxygen to produce gaseous carbon dioxide and gaseous water .…

A: Given  Mass of hexane= 16.4 g mass of oxygen = 25.0 g to find mass of carbon dioxide =?

Q: The bond angle of H-O-C₁ is The bond angle of O-C₁-N is [Select] [ Select] The bond angle of C₁-N-C₂…

A: First let us consider the hybridisation of different atoms in isocyanomethanol. O atom= sp3…

Q: See Figure 2-4. The MOST correct line drawing for the molecule shown is O A B

A: We are given structure of an organic molecule and asked to choose the correct bond line structure…

Q: Pu-238 undergoes alpha decay .show an equation

A:

Q: What is the simplest formula for this structure as well as its coordination number of A and B. (A:…

A: we have to write formula and coordination number

Q: a. For the following unbalanced reaction, suppose exactly 6.20 g of each reactant is taken.…

A: Given that , A unbalanced reaction  Na2B4O7 (s) + H2SO4 (aq) + H2O (l) → H3BO3 (s) + Na2SO4(aq)  If…

Q: en solutions of silver nitrate and potassium chloride are mixed, silver chloride precipitates out of…

A: Given -> AgNO3(aq) + KCl(aq) ---> AgCl(s) + KNO3(aq)  Volume of AgNO3= 1.34 L = V1…

Q: Directions: Encircle the correct answer. 1. The electronic structures of various atoms are shown…

A: Octet rule: According to this rule atoms are more stable when they have eight electrons in their…

Q: a. For the following unbalanced chemical equation, suppose 10.6 g of each reactant is taken. Show by…

A: a) Limiting reactant: A reactant that is totally consumed when the chemical reaction is completed is…

Q: How much work is done when 12 moles of CO₂ are produced in a combustion reaction of CeHe at 298 K?…

A: Answer: In the given chemical reaction combustion of 1 mole benzene is taking place in presence of…

Q: 2. Please sketch a 4dx2-y2 orbital, indicating the axis sytem, and the number of angular and radial…

A:

Q: You wish to prepare 100.0 mL of a 750.0 ppm w/v sodium (MW = 22.9897 g/mol) solution. How many grams…

A: Given: Volume of solution = 100 mL w/v concentration of Na = 750.0 ppm Molar mass of Na = 22.9897…

Q: For Enolates, Which lead to the kinetic and thermodynamic products? A Kinetic 오 B Thermodynamic C D

A: The more substituted enolate is called thermodynamic enolate because of its greater stability. The…

Q: If 85J of heat is added to a pure gold coin with a mass of 13g , what is the temperature change? The…

A: Specific heat of a substance is defined as energy needed to raise the temperature of 1gram of mass…

Q: A student dissolves 7.9 g of styrene (CHg) i in 325. mL of a solvent with a density of 0.84 g/mL.…

A: We have been given volume of solvent = 325mL, density of solvent= 0.84g/mL and mass of styrene =…

Q: 2. Consider the following reaction: 3Si+2N₂-S₂N₁ a. When 21.44 moles of Si react with 17.62 moles of…

A: Given 3Si + 2N2 →Si3N4

Q: See Figure 2-2. Match each atom to its hybridization. C-1 is : C-2 is: C-3 is : Nis O is

A:

Q: Part A What is the concentration of K+ in 0.15 M of K₂S? Express your answer to one decimal place…

A: Molarity (M) is a concentration term for a solution. The molarity of a solution is defined as the…

Q: 3- Draw the correct structures of the following: 1-1,2-Dimethylcyclohexene…

A:

Q: When 158. g of glycine (C,H, NO.) are dissolved in 1000. g of a certain mystery liquid X, the…

A:

Q: Question 6 For this reaction occurring at 20 °C, the following data was obtained. C6H12O + Br2 →…

A: Given, C6H12O + Br2 ---> C6H11OBr + HBr Rate constant (k) = ? Run C6H12O Br2 initial Rate…

Q: Find the solubility of lead(II) sulfate in 0.39 M Na2SO4 (aq). The solubility product of lead (II)…

A: Given , Solubility product of lead (II) sulfate 1.6×10-8

Q: Give typed answer not written What are resonance structures for these molecules?

A: When there is delocalization of pi-electrons or lone pair of electrons , then resonance structures…

Q: Starting with propyne and using any other required reagents, show how you would synthesize (2R,…

A: This question is based on conversion of a organic compound into another organic compound.

Q: How much heat was absorbed (in J) if a 35.0 g sample of an alloy with a specific heat of 0.189 J/g…

A:

Q: For the structure below, draw the resonance structure that is indicated by the curved arrow(s). Be…

A: Resona

Q: What type of bond results from the side-on overlap of orbitals? 88 o (sigma) bond hydrogen bond…

A: