Honors Chemistry First Semester Test Review
27.) A 25.0 gram lead ball at 45.0°C was heated with 50.9 Joules of heat. Given the specific heat of lead is 0.128 J/g°C, what is the final temperature of the lead?
q=mcΔT 50.9 J = (25.0g)(.128J)(ΔT) ΔT=15.9°C F-I=ΔT F-45.0°C=15.9°C F=60.9°C
14.) Using a table of specific heat capacity values from your notes what is the identity of a 25.0 gram metal sample that increases by 16.0°C when 51.2 Joules of energy is absorbed?
q=mcΔT 51.2J=(25.0g)(c)(16.0°C) c=.128 Gold
12.) What is the final temperature of 56.0 grams of water at 24.0°C after it absorbs 518 Joules of heat?
q=mcΔT 518J=(56.0g)(4.184J)(ΔT) 2.2=ΔT F-I=ΔT F-(24.0°C)=2.2 F=26.2°C
39.) What is the specific heat in J/g°C of a metal object whose temperature increases by 9.0°C when 23.9 grams of metal was heated with 59.6 Joules?
q=mcΔT 59.6J =(23.9g)(c)(9.0°C) c= .28 J/°C
13.) How much heat in kJ is absorbed by 1848.0 grams of water in order for the temperature to increase from 35.00°C to 42.50°C?
q=mcΔT kJ=(1848.0g)(4.184J)(7.5°C) q=57990.24J q=57.9kJ
26.) How much heat in kilojoules is needed to raise the temperature of 356.0 grams of water from 74.5°C to 95.8°C?
q=mcΔT kJ=(356.0g)(4.184J)(21.3°C) 31726.4 J 31.7 kJ
94.) What is the atomic mass of an element equal to?
the sum of the protons and neutrons
61.) List the parts of the scientific method.
Observation, Hypothesis, Experimentation, formulation of Laws and Theories
85.) What are physical changes? List 7.
Physical changes: Changes in the properties of matter that do not affect its composition 1.) Evaporation 2.) Melting 3.) Sublimation 4.) Freezing 5.) Condensation 6.) Deposition 7.) Dissolving
83.) What are physical properties? List 6.
Physical properties: the characteristics of matter that can be changed without changing its composition 1.) Boiling Point 2.) Mass 3.) Color 4.) Malleability 5.) Density 6.) Ductility
99.) Calculate that atomic mass of carbon in C-12 is 40.0% abundance, C-14 is 25.0%, C-16 is 15.0% and C-18 is 20.0%
(12)(.400)+(14)(.250)+(16)(.150)+(18)(.200) 4.8+3.5+2.4+3.6 Atomic Mass= 14.3
65.) Consider and element W that has two naturally occurring isotopes with the following percent abundances: the isotope with a mass number of 60 is 35% abundant; the isotope with a mass of 64 is 65% abundant. What is the average atomic mass for element W?
(60)(.35)+(64)(.65) 21+ 41.6 Average Atomic Mass= 62.6
42.) How many Joules are there in a 475 calorie snack bar?
1 cal = 4.184 J 1990J
45.) How many kilojoules are there in 205.0 calories?
1 cal = 4.184J 857.72J 1000 J = 1kJ .8577 kJ
18.) List at least 3 differences between a mixture and a compound.
1. A mixture is not chemically combined but a compound is 2. A mixture can be separated physically whereas a compound can only be chemically 3. Components of a compound are in fixed proportions whereas mixtures are in any proportion
21.) List 5 processes that do NOT involve a change in chemical properties.
1. Boiling 2. Freezing 3. Molding 4. Conducting electricity 5. Melting
5.) List 4 physical properties of water.
1. Liquid 2. Boils at 100°C (high specific heat capacity) 3. Odorless 4. Colorless
74.) List 5 facts about atoms.
1.) contains protons, neutrons, and electrons 2.) smallest particles that make up elements 3.) mostly empty space 4.) Atoms are extremely small 5.) exists as electrically neutral, or ions
87.) List 3 facts about a solution.
1.) homogeneous mixture 2.) composed of 2 or more substances 3.) can exist in any phase
73.) List the parts of Dalton's atomic theory.
1.)Matter is composed of indivisible particles (atoms) 2.)All atoms of a particular element are identical 3.)Different elements have different atoms 4.)Atoms combine in certain whole-number ratios 5.)In a chemical reaction, atoms are merely rearranged to form new compounds; they are not created, destroyed, or changed into atoms of any other elements
6.) List 5 physical changes you could make to a metal.
1.)malleable 2.)boil 3.)melt 4.)cut 5.)bend
72.) How is an atomic unit defined?
1/12 the mass of carbon (in the past: 1 Hydrogen atom)
57.) How many calories are there in a 657 Calorie snack bar?
1000 cal = 1 Cal 657,000 calories
37.) Express the sum of 6.87 m and 9.0 m using the correct number of number of sig figs.
16m
11.) What is the value of 467K in units of °C?
194 °C
75.) Name the following groups: 1A, 2A, 5A, 6A, 7A, 8A
1A: Alkali Metals 2A: Alkali Earth Metals 5A: Nitrogen 6A: Oxygen 7A: Halogens 8A: Noble Gases
51.) In the number 67.892, which digit is estimated?
2
52.) How many significant figures are there in the answer to the following calculation? (234) x (0.79 x 6.89358)
2 significant figures
25.) What is the result of adding (7.8x10⁴) + (8.9x10³)?
86900 8.69x10⁴ With sig figs: 8.7x10⁴
34.) If the temperature changes by 273K, by how much does it change in °C?
273°
92.) How many significant figures are in the number 6.00 x 10⁻³?
3
33.) What is the measurement 3345.0009 rounded off to five significant digits?
3345.0
24.) What is the result of multiplying (5.6x10⁹) x (7.5x10⁻⁶)?
42000 4.2x10⁴
49.) How many significant digits are there in the answer to the following calculation? (5.765) + (2002.8)
5 significant digits
44.) What is the value 273°C on the Kelvin temperature scale?
546K
35.) Express the product of 6.7x10⁻⁶ and 9.87x10⁵ using the correct number of sig figs.
6.6
93.) What is the correct scientific notation for the following numbers? 60.0 , 10100 , 700.00 , 2005
60.0- 6.00x10 10100- 1.01x10⁴ 700.00- 7.0000x10² 2005-2.005x10³
36.) What is the measurement 7054 L rounded off to two sig figs?
7100L
38.) Express the sum of 3333 km and 4440 km using the correct number of sig figs.
7770m
31.) In the measurement 56.78 mL, which digit is the estimated digit?
8
8.) Define and describe a compound.
A compound can be separated into simple substances unlike an element and is formed when 2 or more elements are chemically bonded together (can be ionic or covalent)
7.) Define and describe a homogeneous mixture.
A homogenous mixture is uniform throughout, made of many substances that appear to be one. All portions of a sample have the same composition and properties and are made up of pure substances
62.) What is the scientific method?
A process for trying to understand nature by observing nature and the way it behaves, and by conducting experiments to test our ideas
63.) What is a scientific law? Define and explain.
A scientific law is a statement based on repeated experimental observations that describes some aspects of the universe. Laws answer the question "What" will happen
10.) Define a substance and list 4 things that are NOT a substance.
A substance is matter which has a specific composition and specific properties. Not a substance: Salt water, gasoline, steel, brass
60.) Define and explain what a hypothesis is.
A tentative prediction of the outcome of an experiment, usually using "if" and "then"
90.) Dalton theorized that atoms are indivisible and that all atoms of an element are identical. What do we know now?
Atoms can be divided, but only in a nuclear reaction. Atoms are not all identical because of isotopes.
28.) Look up the specific heats of the following metals: Al, Pb, Ag, Fe, and Cu. If the same amount of heat is added to 35.5 gram samples of each of the metals, which are all at the same temperature, which metal will reach the highest temperature?
Al: 0.903 Pb: 0.128 Ag: 0.235 Fe: 0.449 Cu: 0.385 Lead will reach the highest temperature
47.) List the rules for determining significant figures.
All non-zero digits are significant Interior zeros are significant Trailing zeros with a decimal point are significant Leading zeros are not significant Trailing zeros without a decimal point are not significant Exact numbers have an infinite number of significant figures Adding and Subtracting: significant decimals Multiplying and Dividing: significant figures
16.) What happens to the individual atoms in a chemical reaction?
Atoms between the reactants are broken, and atoms rearrange and form new bonds to make the products.
71.) Where are metals, nonmetals, and metalloids located on the periodic table?
Metals: left Metalloids: bordering the stair step line Nonmetals: right
9.) Why does a golf ball have more mass than a tennis ball?
Because it is is denser and not hollow in the middle
40.) What is the boiling point and freezing point of water in °F, °C, and K?
Boiling: 212°F, 100°C, 373K Freezing: 32°F, 0°C , 273K
84.) What are chemical properties? List 4.
Chemical properties: characteristics that determine how the composition of matter changes as a result of contact with other matter or the influence of energy 1.) Reactivity 2.) Caustic 3.) Flammability 4.) Toxicity
56.) Explain what is happening when the paint on a vehicle fades over time.
Chemical changes are happening and they are happening NOW pLeAsE bE aWaRe tHeY aRe HAPPENING!!!!!!!!!!!!!!!!!!!!!!!!!!!!
86.) What are chemical changes? List 4.
Chemical changes: involve a change in the properties of matter that change its composition 1.) Fermentation 2.) Burning 3.) Rusting 4.) Exploding
81.) Define the following: compound, homogeneous mixture, pure substance, solid, liquid, gas, matter.
Compound: The result of two or more elements chemically combining into fixed ratios. Homogeneous Mixture: A mixture that has the same composition throughout. Pure substance: Made up of the same elements in the same continuous composition Solid: The state of the least movement of the particles. typically hard and brittle. Liquid: The state where the particles slide past one another slowly. Flows. Gas: The state where particles rapidly pass by each other. Indefinite volume and shape. Matter: Anything that takes up space and possesses weight.
50.) What is the density of 879 mL of a liquid that has a mass of 634.8 grams?
D = m/V D =634.8g/879mL D= .722 g/mL³
98.) What is the density of an object that has a mass of 34.70 grams and, when placed into a graduated cylinder, cases the water level to rise from 45.6 to 67.0 mL?
D= m/V 67.0-45.6= 21.4mL D= 34.70/21.4 D= 1.62 g/mL³
32.) What is the volume in mL of 256.0 grams of ether if the density of ether is 0.10 g/mL?
D= m/V V= m/D V= 256.0g/0.70 g/mL V= 370mL³
97.) Suppose a boat engine leaks 469 mL of oil into a lake. The mass of this spilled oil is 411 grams. What is the density of the oil? Will it sink or float? Explain.
Density of water: 1 D= m/V D= 411/469 D= .876 g/mL³ The oil will float because it is less dense than water.
95.) How do the isotopes of C-12 and C-14 differ? How are they the same?
Different number of neutrons Same number of protons
55.) Define energy and list two facts about energy.
Energy is anything that has the capacity to do work. They do not have mass and volume. It cannot be created of destroyed
64.) Name something that does not contain chemicals.
Energy(AND A HOOKERS SOUL)
4.) List two examples of something that is NOT matter.
Heat and energy
53.) List four common units of energy.
Joules, calories, Calories, kWh
70.) Who first arranged the elements according to atomic mass and noticed a periodic recurrence of their physical and chemical properties?
MEDELEEV
22.) What is true about mass in all chemical reactions?
Mass is neither created nor destroyed
82.) What is the mass number of the nitrogen isotope that contains 6 neutrons?
Mass: 13 amu
1.) How is matter defined?
Matter is defined as anything that occupies space and has mass.
58.) When methane is burned with oxygen the products are carbon dioxide and water. If you produce 72 grams of water and 88 grams of carbon dioxide from 32 grams of methane, how many grams of oxygen were needed for the reaction?
Methane + Oxygen = Carbon Dioxide + Water 32 + Oxygen = 72 +88 128g of Oxygen
88.) Define a mixture. What are the two major types of mixtures? Define them.
Mixture: has variable composition, different samples may show different properties, separate components based on physical properties Homogeneous: Mixtures that are uniform throughout, also known as solutions Heterogeneous: Mixtures that have regions with different characteristics, not uniformly distributed
54.) Which type of energy is associated with motion? with position?
Motion: Kinetic Position: Potential
77.) How many neutrons are present in Ne-35, O-20, and H-1?
Ne-35: 25 O-20: 12 H-1: 0
78.) How many protons and electrons are present in S²⁻?
Protons: 16 Electrons: 18
89.) Compare the mass and charge of the three main subatomic particles.
Protons:(+) 1.007 amu Neutrons:(0) 1.009 amu Electrons: (-) 0.0005 amu
79.) Know the difference between pure research and applied research.
Pure Research: simply aims to advance knowledge Applied Research: used order to solve specific, practical questions or problems
80.) Know how to express numbers in scientific notation and how to take numbers out of scientific notation.
Put numbers into scientific notation: Big to small: move decimal to left, positive exponent Small to big: move decimal to right, negative exponent Take numbers out of scientific notation: Negative Exponent: move decimal to the left Positive Exponent: move decimal to the right
20.) What information does the chemical formula of a compound give? What does it not give?
The chemical formula of a compound doesn't give the arrangement of atoms, but it does give the charge, what type of elemtns, and how many of each element there is
19.) How will the mass of a tarnished candle stick compare to the mass of the candle stick before it tarnished?
The mass of a tarnished candlestick will be greater the normal candle stick.
91.) In a conversion factor such as 1000 calories = 1 kilocalorie, how many significant figures are you limited to?
There is an infinite number of significant figures
48.) What is the volume of 45.78 grams of liquid that has a density of 0.789 g/mL?
V= m/D V= 45.78g/0.789 g/mL V=58.0mL³
76.) Define isotopes.
When an element's atoms have different numbers of neutrons, they are said to be isotopes of that element.
67.) What does the periodic law state?
When the elements are arranged in order of increasing atomic number (in the past: increasing atomic mass)
59.) What is a good definition of chemistry?
a science that deals with the structure and properties of substances and with the changes that they go through
68.) How is the modern periodic table arranged?
by atomic number
43.) In calculating the relationship between the amount of heat added to a substance and the corresponding temperature change, the specific heat capacity is usually represented by what symbol?
c
23.) Using a table of specific heat capacity values from your notes what is the identity of a 56.0 gram metal sample that increases by 26.0°C when 1314.77 Joules of energy is absorbed?
q=mcΔT 1314.77=(56.0g)(c)(26.0°C) c=.903 Aluminum
17.) When paper becomes yellow-brown in color upon exposure to sunlight, what type of change is likely taking place?
chemical change
15.) What is a homogeneous substance that can be separated into two or more pure substances only by a chemical change?
compound
30.) As the density of a substance increases, what happens to the volume of a given mass of that substance?
decreases
66.) Which subatomic particle plays the greatest part in determining the physical and chemical properties of an element?
electrons
41.) If a particular process is exothermic, the reverse process must be what?
endothermic
96.) Why are all atoms neutral with no charge?
equal number of protons and electrons
46.) When a large amount of heat is released during a chemical change, is the process endothermic or exothermic?
exothermic
2.) List 4 physical properties of a substance in the liquid state.
indefinite shape, definite volume, cannot compress, flows
3.) A substance that forms a vapor is generally in what physical state at room temperature?
liquid or solid
69.) What does the atomic mass of an element depend on?
protons and neutrons
29.) When 101.0 Joules of heat was transferred to 7.3 grams of a metal at 33.0°C, the temperature of the metal increases to 47.0°C. What is the specific heat of the metal in J/g°C?
q=mcΔT 101.0J =(7.3g)(c)(14.0⁰) c= .99 J/°C