Laird - University Chemistry 1/e (Homework)

Chris Read

McGraw-Hill, section 1, Fall 2010

Instructor: Dr. Friendly

Current Score : 0 / 10

Due : Saturday, October 16, 2010 07:00 AM EDT

Question

Points

1	2	3	4	5
0/5	0/2	0/1	0/1	0/1

Total

0/10

Description

University Chemistry 1/e by Laird published by McGraw-Hill Higher Education now has animations with conceptual questions and tutorial problems offering feedback and hints to guide student content mastery, as well as over 1150 end-of-chapter questions. You can check out a sampling of this exciting development below.

Designed by teachers for teachers, WebAssign is easy to use and reliable -- a trusted companion to your teaching. Sign up for a Free Trial today!

Click here for a list of all of the questions coded in WebAssign.

Question 1 is an animation with an assignable quiz attached.

Question 2 is a follow-up Practice Exercise which checks student understanding of the related Example in the textbook. Practice Exercise 13, for example, is directly related to Exercise 13.

Question 3 and 4 are algorithmic end-of-chapter problems with conditional feedback added to the numerical answers.

Question 5 is a testbank question.

Instructions

This demo assignment allows many submissions and allows you to try another version of the same question for practice.

1. –/5 points Notes Question: LairdUChem1 0.Animation.01.

Question part

Points

Submissions

1	2	3	4	5
0/1	0/1	0/1	0/1	0/1
0/50	0/50	0/50	0/50	0/50

Total

0/5

Limiting Reactant

Use the animation to answer the following questions.

(a) In the animation reaction, if 4 NO and 4 O₂ are mixed, how many molecules of the product form?
molecules

(b) When 6 NO and 3 O₂ are used in the reaction in the animation, the limiting reactant is:

O₂ NO₂ There is no limiting reactant in this case. NO

the stoichiometric ratio for the reaction. the initiation of the reaction. that excess reactant is in the right bulb. that limiting reactant is in the left bulb.

This animation will begin with a narration when you click "Open in New Window" below. To restart the narration, click "Open in New Window" again.

(d) If there is excess oxygen present in the reaction, this can be seen in the animation by the presence of:

molecules containing two red spheres and one blue sphere at the end of the reaction molecules containing one red sphere and one blue sphere at the end of the reaction. molecules containing two red spheres and two blue spheres during the reaction. molecules containing two red spheres at the end of the reaction

(e) Which of the following characterizes the reaction shown in the animation which utilizes the 6 NO to 2 O₂ mole ratio?

O₂ is the excess reactant. NO is the limiting reagent. NO remains at the end of the reaction. More product is produced than in the other combinations.

2. –/2 points Notes Question: LairdUChem1 0.PracticeEx.17.

Question part

Points

Submissions

1	2
0/1	0/1
0/50	0/50

Total

0/2

Practice Exercise 0.17

The reaction between nitric oxide (NO) and oxygen to form nitrogen dioxide (NO₂) is a key step in photochemical smog formation.

2 NO(g) + O₂(g) 2 NO₂(g)

(a) How many moles of NO₂ are formed by the complete reaction of 0.284 mole of O₂?

WebAssign will check your answer for the correct number of significant figures.

moles
(b) How many grams of NO₂ are formed by the complete reaction of 3.24 g of NO?

grams

HINTS

I'm Stuck

3. –/1 points Notes Question: LairdUChem1 0.EOCP.055.

Question part

Points

Submissions

1
0/1
0/50

Total

0/1

Each copper(II) sulfate unit is associated with five water molecules in crystalline copper(II) sulfate pentahydrate (CuSO₄·5 H₂O). When this compound is heated in air above 100°C, it loses the water molecules and also its blue color.

CuSO₄·5 H₂O

CuSO₄ + 5 H₂O

If 8.80 g of CuSO₄ are left after heating 13.76 g of the blue compound, calculate the number of moles of H₂O originally present in the compound.

moles

4. –/1 points Notes Question: LairdUChem1 3.Supp.7-09.

Question part

Points

Submissions

1
0/1
0/50

Total

0/1

Which of the following chemical equations is NOT balanced?

H₂SO₄(aq) + Mg(OH)₂(s)

2 H₂O(l) + MgSO₄(s) 2 H₃PO₃(aq) + 3 Ca(OH)₂(s)

6 H₂O(l) + Ca₃(PO₃)₂(s) C₈H₁₈(l) + 5 O₂(g)

9 H₂O(g) + 8 CO₂(g) CH₄(g) + 2 O₂(g)

2 H₂O(g) + CO₂(g)

5. –/1 points Notes Question: LairdUChem1 3.TB.006.

Question part

Points

Submissions

1
0/1
0/50

Total

0/1

The mass of 1.21

10²⁰ atoms of sulfur is

6.44 mg. 3.88

10²¹ g. 2.00

10^-4 g. 2.00 mg. 32.06 g.

WebAssign

Logged in as mcgraw@mcgraw

Laird - University Chemistry 1/e (Homework)

Current Score : 0 / 10