Problems 1-17 part 1

1. A.  (6.6*10^-8)+(5.0*10^-9) =  7.1e-8

    B. (9.4*10^2)-(2.1*10-2)= 0.073

2.  (6.6*10^6)/((8.8*10^-2)*(2.5*10^3)) = 30,000

3.  A student measures the depth of a swimming pool to be 2.04 meters at its deepest end.                              The accepted value is 2.00m.  What is the student’s percent error?

    ((2.04 - 2.00)/2.00)*100= 2% error

13. How can you express a number in scientific notation.

Express a number in scientific notation by dividing a number by ten until you create a coefficient, then multiply the coefficient by 10 to the power of the amount of times you divided by ten.  

15.  A technician experimentally determined the boiling point of octane to be 124.1 degrees celsius.  The actual boiling point of octane is 125.7 degrees celsius.  Calculate the error and the percent error.

    124.1 - 125.7 = -1.6 (error) and -1.6/125.7 = about -1 percent error

17. Solve the following and express each answer in scientific notation and to the correct number of significant figures.

    a. (5.3 * 10^4)+(1.3* 10^4) = 6.6 * 10 ^ 4

    b. (7.2 *10^−4)/(1.8 *10^3) = 4.0 * 10 ^ -7

    c. 10^4 * 10^−3  * 10^6 = 1.0 * 10 ^ 7

    d. (9.12 * 10^−1) - (4.7 * 10^−2) = 8.6 * 10^1

    e. (5.4 * 10^4) * (3.5 * 10^9) = 1.89 * 10 ^ 14

Popcorn Lab

Sigfigs work

Problems 1-17

1. A.  (6.6*10^-8)+(5.0*10^-9) =  7.1e-8

   B. (9.4*10^2)-(2.1*10-2)= 0.073

2.  (6.6*10^6)/((8.8*10^-2)*(2.5*10^3)) = 30,000

3.  A student measures the depth of a swimming pool to be 2.04 meters at its deepest end.                              The accepted value is 2.00m.  What is the student’s percent error?

((2.04 - 2.00)/2.00)*100= 2% error

13. How can you express a number in scientific notation.

Express a number in scientific notation by dividing a number by ten until you create a coefficient, then multiply the coefficient by 10 to the power of the amount of times you divided by ten.  

15.  A technician experimentally determined the boiling point of octane to be 124.1 degrees celsius.  The actual boiling point of octane is 125.7 degrees celsius.  Calculate the error and the percent error.

124.1 - 125.7 = -1.6 (error) and -1.6/125.7 = about -1 percent error

17. Solve the following and express each answer in scientific notation and to the correct number of significant figures.
a. (5.3 * 10^4)+(1.3* 10^4) = 6.6 * 10 ^ 4
b. (7.2 *10^−4)/(1.8 *10^3) = 4.0 * 10 ^ -7
c. 10^4 * 10^−3  * 10^6 = 1.0 * 10 ^ 7
d. (9.12 * 10^−1) - (4.7 * 10^−2) = 8.6 * 10^1
e. (5.4 * 10^4) * (3.5 * 10^9) = 1.89 * 10 ^ 14

Problems 32-66

32.Explain How does a chemical change affect the composition of matter?
By breaking it down into base elements.

33.List Name four possible clues that a chemical change has taken place.
1. Color change

2. Smoke

3.Heat

4. Explosion

34.Compare In a chemical reaction, how does the mass of the reactants compare with the mass of the products?
The mass is the same.

35.Compare What is the main difference between physical changes and chemical changes?

Physical changes do not change the elements structure, only its state of matter.                                                                                   36.Classify Classify the following changes as physical or chemical changes.
a.Water boils. Physical

b.Table salt dissolves in water. Physical
c.Milk turns sour. Chemical
d.A metal rusts. Chemical                                                                                                                   40.List three physical properties of copper.
41.Name two physical properties that could be used to distinguish between water and ethanol.
42.Name one physical property that could not be used to distinguish chlorine from oxygen.
43.What is the physical state of each of these materials at room temperature?
a.gold Solid

b.gasoline Liquid
c.oxygen Gas
d.neon Gas

e.olive oil Liquid

f.sulfur Solid
g.mercury Gas                                                                                                     44.Fingernail-polish remover (mostly acetone) is a liquid at room temperature. Would you describe acetone in the gaseous state as a vapor or a gas? Explain your answer.

Acetone in the gaseous state is a vapor because acetone in room temperature is a liquid.

50. Classify each of the following as a homogeneous or heterogeneous mixture.
a. chocolate-chip ice cream Heterogenous
b. green ink Homogenous
c. cake batter Heterogenous
d. cooking oil Homogenous
e. granite rock Homogenous
f. salt water Heterogenous
g. paint Homogenous
h. a silver ring Homogenous

54.Describe the relationship between the three items in each of the following groups. Identify each item as an element, compound, or mixture.
a. hydrogen, oxygen, and water Compound
b. nitrogen, oxygen, and air Compound
c. sodium, chlorine, and table salt Mixture
d. carbon, water, and table sugar. Mixture

60. Classify each of the following as a physical or chemical change. For any chemical change, list at least one clue to support your answer.
a. A copper wire is bent. Physical
b. Charcoal burns in a grill.Chemical (smoke)
c. Bread dough rises when yeast is added. Physical
d. Sugar dissolves in water. Physical

63.Which colorless substance is a liquid at −30°C?

Ethanol
64.Which colorless substance is a gas at 60°C?

Neon
65.Which substance is a solid at 7°C?

Sulfur
66.As the temperature rises, which solid will melt before mercury boils?

All other elements will melt before mercury boils

Textbook Problems

1.All samples of a given substance have the same intensive properties because all substances have certain properties.

2. Three states of matter are solid, liquid, and gas.

3. The two categories used to classify physical changes are reversible and irreversible.

4.Identify Name two categories used to classify properties of matter.

Intensive and Extensive properties.
5.Interpret Tables Which property in the Physical Properties of Some Substances table can most easily distinguish sodium chloride from the other solids?

The color is the only white one.

6.Compare and Contrast In what way are liquids and gases alike? In what way are liquids and solids different?

Liquids and gases are similar because they both have an indefinite shape.  They      are different because gas does not have a fixed volume whereas water does.
7.Explain Is the freezing of mercury a reversible or irreversible physical change? Explain your answer.

Freezing mercury is a reversible physical change because you can melt it again.
8.Explain why samples of platinum and copper can have the same extensive properties but not the same intensive properties.

Because some copper or platinum have different types causing them to be different even though they are the same in mass.                                                                          

12.Identify How are mixtures classified?

Homogenous and Heterogenous
13.List What type of properties can be used to separate mixtures?

Filtration and Distillation
14.Explain the term phase as it relates to homogeneous and heterogeneous mixtures

Phase is used to describe any part of a sample with uniform composition and                               ‘          properties.
15.Classify Classify each of the following as a homogeneous or heterogeneous mixture.
a. food coloring Homogenous
b. ice cubes in liquid water Heterogenous
c. mouthwash Homogenous
d. mashed, unpeeled potatoes Heterogenous
16.Compare and Contrast How are a substance and a solution similar? How are they different?

Substances and solutions are both unifor, but a solution is a mixture of multiple substances.
(I didnt quite get where 20 and 21 were)

12.Compare How is a compound different from an element?

A compound is made up of multiple elements
23.Compare How can you distinguish a substance from a mixture?

A Substance has a definite composition where as a mixture has a variable compostion
24.Identify What are chemical symbols and chemical formulas used for?

They are used to determine what things are made of and what they will make if combined.
25.Explain What makes the periodic table such a useful tool?
26.Identify Name two methods that can be used to break down compounds into simpler substances.
27.Classify Classify each of these samples of matter as an element, a compound, or a mixture.
a. table sugar compound
b. tap water compound
c. cough syrup mixture
d. nitrogen 28.

Identify Write the chemical symbol for each of the following elements:
a. lead           Pb
b. oxygen      O
c. silver      Ag
d. sodium      Na
e. hydrogen   H
f. aluminum  Al
29.Identify Name the chemical elements represented by the following symbols
a. C Carbon
b. Ca Calcium
c. K Potassium
d. Au Gold
e. Fe Iron
f. Cu Copper