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WebAssign General Chemistry (Homework)

James Finch

Chemistry - College, section 1, Fall 2019

Instructor: Dr. Friendly

Current Score : 17 / 24

Due : Tuesday, March 24, 2020 19:00 EDT

Last Saved : n/a Saving...  ()

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17/24 (70.8%)

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    WebAssign General Chemistry, published by WebAssign, is a collection of peer-reviewed questions developed by expert chemistry educators. Designed to support any General Chemistry course or textbook, this robust collection features a series of multi-step tutorials, integrated feedback, and detailed solutions for every question.

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    Final Exam Questions assess students’ ability to integrate a wide range of chemical concepts in a single question, suitable for final exams or year-end reviews.

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1. –/1 points WAGenChem1 8.5.002. My Notes
Question Part
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Calculate the number of moles of potassium permanganate (KMnO4) corresponding to 236.7 g of the substance.
WebAssign will check your answer for the correct number of significant figures.(No Response) mol
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2. –/2 points WAGenChem1 8.3.002. My Notes
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(a) How many moles of CO2 contain 2.29 ✕ 1024 molecules?
WebAssign will check your answer for the correct number of significant figures.(No Response) mol CO2

(b) What number of moles is equivalent to 6.34 ✕ 1021 atoms of Hg?
WebAssign will check your answer for the correct number of significant figures.(No Response) mol Hg
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3. –/5 points WAGenChem1 2.SA.5.010. My Notes
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–/5
 
This question has several parts that must be completed sequentially. If you skip a part of the question, you will not receive any points for the skipped part, and you will not be able to come back to the skipped part.

Tutorial Exercise
Write the molecular and empirical formulas for the compound with the following structural formula.
Step 1 of 4
Write the given structural formula of the compound.
(No Response)


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4. –/1 points WAGenChem1 2.5.016. My Notes
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1
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–/1
 
A compound has an empirical formula of C2H4O and a molar mass of 176 g/mol. What is the molecular formula?

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5. –/1 points WAGenChem1 8.EX.019. My Notes
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A forensics laboratory received a sample of white powder that was suspected of being ecstasy (C11H15NO2), heroin (C21H23NO5), morphine (C17H19NO3), or demerol (C15H21NO2). The results of an elemental analysis performed on the substance are 68.37% carbon, 7.82% hydrogen, 7.25% nitrogen, and 16.56% oxygen. What is the identity of the unknown substance?
    

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6. –/3 points WAGenChem1 8.EX.020. My Notes
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1 2 3
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–/3
 
A 0.5857 g sample of an unknown acid was titrated with NaOH and found to contain 3.510 ✕ 10−3 mol acid. Another sample of the substance was subjected to elemental analysis, where it was determined that the composition of the unknown material is 57.18% C, 4.78% H, and 38.04% O.
(a) What is the molar mass of the unknown acid?
WebAssign will check your answer for the correct number of significant figures.(No Response) g/mol

(b) What is the empirical formula of the unknown acid?

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(c) What is the molecular formula of the unknown acid?

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7. –/2 points WAGenChem1 7.2.005. My Notes
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Determine whether 8 H2 + S8 → 8 H2S obeys the law of conservation of mass and justify your response.
Mass (No Response) been conserved in this reaction because the total mass of the reactants is (No Response) the total mass of the products.
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8. –/6 points WAGenChem1 7.2.004. My Notes
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Methane gas (CH4) reacts with chlorine gas (Cl2) to produce liquid carbon tetrachloride (CCl4) and hydrogen chloride gas (HCl). The balanced chemical equation for the reaction is the following.
CH4(g) + 4 Cl2(g) → CCl4(l) + 4 HCl(g)
Calculate and compare the numbers of atoms of each element on the reactant and product sides of this chemical equation.
In the chemical equation given, (No Response) C atom(s), (No Response) H atom(s), and (No Response) Cl atom(s) are present on the reactant side and (No Response) C atom(s), (No Response) H atom(s), and (No Response) Cl atom(s) are present on the product side.
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9. –/1 points WAGenChem1 7.3.004. My Notes
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1
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–/1
 
Four moles of hydrogen iodide (HI) gas react with one mole of oxygen (O2) gas to produce two moles of iodine gas (I2) and two moles of water gas (H2O). Using this description of the reaction, write the corresponding chemical equation, showing the appropriate coefficients for each reactant and product. (Include states-of-matter under the given conditions in your answer.)

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10. –/2 points WAGenChem1 8.EX.014. My Notes
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Sodium azide, NaN3, is the primary gas-forming compound present in many car airbag systems. It is synthesized by reacting sodium amide, NaNH2, with the gas nitrous oxide, N2O, according to the following equation.
2 NaNH2 + N2O → NaN3 + NaOH + NH3
A sample of sodium azide is prepared by reacting 20.94 g NaNH2 with 11.18 g N2O.
(a) What is the limiting reagent?

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(b) How much sodium azide is produced?
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