Question 1

Insight into Materials Selection and Bicycle Frames 
Rank aluminum, steel and titanium in order of increasing stiffness.

Accepted Answer

In terms of stiffness, materials can be ranked based on their modulus of elasticity, also known as Young's modulus. This value measures a material's ability to resist deformation under stress and is typically expressed in gigapascals (GPa). A higher modulus indicates a stiffer material.

For the materials in question, the approximate Young's modulus values are as follows:

- Aluminum: 69 GPa
- Steel: 200 GPa
- Titanium: 116 GPa

Based on these values, the ranking from least stiff to most stiff is:

1. Aluminum
2. Titanium
3. Steel

Therefore, steel is the stiffest of the three materials, followed by titanium, with aluminum being the least stiff. It's important to note that while stiffness is a critical factor in bicycle frame design, other factors such as strength, weight, durability, and ride quality are also important considerations in materials selection.

Question 2

Numbers and Measurements 
Assuming the numbers given are measurements, carry out the indicated arithmetic operations and give the answer with the correct number of significant figures. 
a) 7.132 / 6 
b) 3.65 × 102 + 8.1 × 103 
c) 18.13 − 1.3 
d) 9 × 10 − 6 × 1.33 × 10 − 3

Accepted Answer

a) 1.189 b) 8.5 × 10³ c) 16.8 d) 1 × 10^{− 8}

Question 3

Numbers and Measurements 
Use the web to determine how the btu unit was initially established. For the engineering applications where this unit is still used today, why is it a sensible unit?

Accepted Answer

Utilize a world wide web search engine to acquire the reference.

Question 4

Numbers and Measurements 
The largest computers now include disk storage space measured in terabytes. How many bytes are in a terabyte? (Recall that in computer terminology, the prefix is only "close" to the value it designates in the metric system.)

Accepted Answer

1 terabyte

Question 5

Numbers and Measurements 
Measurements indicate that 23.6% of the residents of a city with a population of 531,314 are college graduates. Considering significant figures, how many college graduates are estimated to reside in this city.

Accepted Answer

The answer of Numbers and Measurements 
Measurements indicate that 23.6%...

Question 6

Problem Solving in Chemistry and Engineering 
A metallic cylinder displaces 91.0 mL and has a mass of 245.7 g. What is the density of the metal?

Accepted Answer

The answer of Problem Solving in Chemistry and Engineering 
A...

Question 7

Focus on Problem Solving Exercises 
If corn is traded by the "bushel" and an acre of crop land yields an average of 240 bushels of corn per acre, how would you determine the volume of corn in L is produced by a 160 acre field? What would you have to look up to solve the problem?

Accepted Answer

One would need to look up the

Question 8

Observations and Models 
What is a law of nature? Are all scientific laws examples of a law of nature?

Accepted Answer

A law of nature is an irrefuta

Question 9

Focus on Problem Solving Exercises 
A student was given two metal cubes that looked similar. One was 1.05 cm on an edge and had a mass of 14.32 grams; the other was 2.66 cm on a side and had a mass of 215.3 grams. How can the student determine if these two cubes of metal are the same material using only the data given?

Accepted Answer

Determine the density of each cube. If t

Question 10

Numbers and Measurements 
In an attempt to determine the velocity of a person on a bicycle, an observer uses a stopwatch and times the length of time it takes to cover 25 "squares" on a sidewalk. A measurement of one of the squares shows it to be 1.13 m long. The bicycle takes 4.82 seconds to travel this far. What velocity, in m/sec, should the observer report?

Accepted Answer

The answer of Numbers and Measurements 
In an attempt to...

Question 11

Focus on Problem Solving Exercises 
Battery acid has a density of 1.285 g/mL and contains 38.0% sulfuric acid by mass. Describe how you would determine the mass of pure sulfuric acid in a car battery, noting what item(s) you would have to measure or look up.

Accepted Answer

Measuring the volume of battery acid and

Question 12

Problem Solving in Chemistry and Engineering 
If the cost to fill a gasoline tank is $78.42 and gasoline costs $3.66/gal, how many gallons does the tank hold? How many L of gasoline could be purchased for $50.00?

Accepted Answer

a) 21.4 ga

Question 13

Numbers and Measurements 
Convert the value 38.4 ppm into ppb.

Accepted Answer

The answer of Numbers and Measurements 
Convert the value 38.4...

Question 14

Observations and Models 
Two golfers are practicing shots around a putting green. Each golfer takes 20 shots. Golfer 1 has 7 shots within 1 meter of the hole, and the other 13 shots are scattered around the green. Golfer 2 has 17 shots go into a small sand trap near the green and three just on the green near the trap. Which golfer is more precise? Which is more accurate?

Accepted Answer

Golfer 2 is more precise because his eff

Question 15

Observations and Models 
Complete the following statement: Data that have a small random error may be (accurate, precise, both, or neither).

Accepted Answer

These data

Question 16

Problem Solving in Chemistry and Engineering 
Carry out the following unit conversions. 
a) 82 μ g to mg 
b) 6.73 × 10 − 4 mm to nm 
c) 1.37 × 106 nA to Ma 
d) 4.8 × 1018 mW to GW

Accepted Answer

a) 8.2 × 10^{− 2} mg b) 6

Question 17

Problem Solving in Chemistry and Engineering 
Mercury has a density of 13.6 g/mL. What is the mass of 4.72 L of mercury?

Accepted Answer

The answer of Problem Solving in Chemistry and Engineering 
Mercury...

Question 18

Numbers and Measurements 
What is the difference between a qualitative and a quantitative measurement?

Accepted Answer

A quantitative measurement pro

Question 19

The Study of Chemistry 
Identify the physical and chemical properties noted in the following statement: When a piece of iron is exposed to air it corrodes, forming a layer of red-brown powder that flakes off and is denser than the original material.

Accepted Answer

Physical properties include th

Question 20

Insight into Materials Selection and Bicycle Frames 
Use the web to research the elastic modulus and yield strength of carbon fiber composites. How do these materials compare to aluminum, steel and titanium?

Accepted Answer

Utilize a world wide

Insight into Materials Selection and Bicycle Frames Rank aluminum, steel and titanium in order of increasing stiffness.

Numbers and Measurements Assuming the numbers given are measurements, carry out the indicated arithmetic operations and give the answer with the correct number of significant figures. a) 7.132 / 6 b) 3.65 × 10² + 8.1 × 10³ c) 18.13 − 1.3 d) 9 × 10^{− 6} × 1.33 × 10^{− 3}

Numbers and Measurements Use the web to determine how the btu unit was initially established. For the engineering applications where this unit is still used today, why is it a sensible unit?

Numbers and Measurements The largest computers now include disk storage space measured in terabytes. How many bytes are in a terabyte? (Recall that in computer terminology, the prefix is only "close" to the value it designates in the metric system.)

Numbers and Measurements Measurements indicate that 23.6% of the residents of a city with a population of 531,314 are college graduates. Considering significant figures, how many college graduates are estimated to reside in this city.

Problem Solving in Chemistry and Engineering A metallic cylinder displaces 91.0 mL and has a mass of 245.7 g. What is the density of the metal?

Focus on Problem Solving Exercises If corn is traded by the "bushel" and an acre of crop land yields an average of 240 bushels of corn per acre, how would you determine the volume of corn in L is produced by a 160 acre field? What would you have to look up to solve the problem?

Observations and Models What is a law of nature? Are all scientific laws examples of a law of nature?

Focus on Problem Solving Exercises Battery acid has a density of 1.285 g/mL and contains 38.0% sulfuric acid by mass. Describe how you would determine the mass of pure sulfuric acid in a car battery, noting what item(s) you would have to measure or look up.

Problem Solving in Chemistry and Engineering If the cost to fill a gasoline tank is $78.42 and gasoline costs $3.66/gal, how many gallons does the tank hold? How many L of gasoline could be purchased for $50.00?

Numbers and Measurements Convert the value 38.4 ppm into ppb.

Observations and Models Complete the following statement: Data that have a small random error may be (accurate, precise, both, or neither).

Problem Solving in Chemistry and Engineering Carry out the following unit conversions. a) 82 μ g to mg b) 6.73 × 10^{− 4} mm to nm c) 1.37 × 10⁶ nA to Ma d) 4.8 × 10¹⁸ mW to GW

Problem Solving in Chemistry and Engineering Mercury has a density of 13.6 g/mL. What is the mass of 4.72 L of mercury?

Numbers and Measurements What is the difference between a qualitative and a quantitative measurement?

The Study of Chemistry Identify the physical and chemical properties noted in the following statement: When a piece of iron is exposed to air it corrodes, forming a layer of red-brown powder that flakes off and is denser than the original material.

Insight into Materials Selection and Bicycle Frames Use the web to research the elastic modulus and yield strength of carbon fiber composites. How do these materials compare to aluminum, steel and titanium?

Atoms and Molecules

Molecules Moles Chemical Equations

Stoichiometry

Gases

The Periodic Table and Atomic Structure

Chemical Bonding and Molecular Structure

Molecules and Materials

Energy and Chemistry

Entropy and the Second Law of Thermodynamics

Chemical Kinetics

Chemical Equilibrium

Electrochemistry

Filters

Exam 1: Introduction to Chemistry