Chemistry 1st Semester Review
Variable
mass
volume (2)
density (2)
Symbol
Units
1. What would the reading on the graduated cylinder to the left be with the
correct number of digits. How many significant figures is the reading?
Hint: We know for sure the value is between what and what? We can estimate
one digit to the right of what we know for certain.
2. Determine the density of each metal. Show your
work.
3. Write the equation for the line of substance A using the correct variable notation and units.
4. How does substance B differ from substance A?
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5. Which would have a larger mass, 50 mL of substance A or 50 mL of substance B? Explain.
6. Calculate the mass of 30.0 cm3 piece of substance B using density. D = m/v
7. Show ALL of your work with the correct units.
Gold has a density of 19.3 g/cm3.
a. What is the volume of 25.0 g of gold?
b. What is the mass of 16 mL of gold?
Lead has a density of 11.34 g/cm3.
a. What is the volume of a cube of lead that measures 2.15 cm on each side?
b. What is the mass of the lead cube?
8. Make the following calculations and round to the correct number of significant digits:
a.
b.
c.
d.
65.12 mL + 4.333 mL = ___________
9.07 m x 85.33 m = _______________
13.00 cm3 ÷ 1.21 cm = ____________
0.0052 s2 ÷ 62.8 s = _______________
9. Determine the relationship, as compared to each other, for each of the following:
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1 cm3 = _____mL
1 gram of H2O = ______mL
10. A graduated cylinder with a volume of 25.0 mL is used to measure the volume of an
irregularly shaped metal object. If the volume of the object was determined to be 18.0 cm3 and it
had a mass of 18.33 g, what is the density of the metal? Sketch a graduated cylinder before
and after the object has been placed in the cylinder.
Gas behavior
11. List the following as either DIRECT or INDIRECT: REMEMBER: PV = nRT
P vs. V = ______________
n vs. T = ______________
P vs. n = ______________
V vs. n = ______________
P vs. T = ______________
V vs. T = ______________
_____
_____
_____
_____
_____
11. In the space provided, list the graphs above as either:
a. Direct
b. Indirect
c. Neither
12. Define gas pressure:
13. Sketch graphs representing the relationships between the following. Include sketches of
particle diagrams on two points on your graph:
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a. P vs V
b. P vs 1/V
c. V vs Tk
d. P vs Tc
e. P vs Tk
f. P vs n
14. Explain why one must use the absolute (Kelvin) temperature scale to solve gas problems.
15. If the volume of a contained gas is tripled, what happens to the pressure if the amount and
temperature remains constant? Sketch a particle diagram to represent initial and final
conditions.
16. Suppose that you lowered the temperature of a gas from 100˚C to 50 ˚C. By what factor do
you change the volume of the gas?
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17. Suppose that 25.0 mL of a gas at 725 mm Hg and 20˚C is converted to standard pressure
and temperature. What would be the new volume?
18. Determine the final pressure of gas that had an initial temperature of 30oC, a pressure of
1.4 atm and a volume of 22.5 mL, when the temperature is changed to 60oC and a volume
of 45 mL.
19. Sketch particle diagrams of a substance in the solid phase, liquid phase, and gas phase.
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20. Explain how the Celsius scale was devised and why it is not appropriate to use it when
describing the behavior of gases. How do we convert between the Kelvin and Celsius
temperature scales?
Kinetic Molecular Theory
This theory describes all matter as being composed of tiny particles in endless random
motion. In a solid, the particles vibrate, but are locked into an orderly array. In a liquid, the
particles are still touching but are free to move around past one another. In a gas, the particles
are moving very rapidly and are widely separated. Using a particle diagrams, represent
samples of a cold gas and a hot gas.
Cold
Hot
Energy
Think of energy as a quantity that is always involved when there is a change in the state of
matter. When a substance gets hotter or colder or changes phase, energy is either transferred
into or out of the system. The two key ways energy is stored is thermal (due to the motion of the
particles) and phase (due to attractions between the particles).
Kinetic Molecular Theory
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This theory describes all matter as being composed of tiny particles in endless random
motion. In a solid, the particles vibrate, but are locked into an orderly array. In a liquid, the
particles are still touching but are free to move around past one another. In a gas, the particles
are moving very rapidly and are widely separated.
When energy is transferred to a sample of matter, either the particles speed up
(temperature increases) or they get pulled apart (phase change), but not both at the same time.
This helps account for the shape of the warming curve you got in the Icy Hot lab.
21. Label which phases are present in each portion of the curve above.
22. Label the sections in which the thermal energy (Eth) of the sample is changing. Label the
sections where the phase energy (Eph) is changing.
23. Describe what is happening during each of the following:
Eth:
Eph:
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24. Label what physical process is occurring at each phase change (freezing, evaporating,
melting, condensing).
Remember that when a substance is heated or cooled the temperature and arrangement of
the molecules change, the molecules are not breaking apart or rearranging to form
something new.
Boiling water turns from liquid water into water vapor.
Condensing water is water vapor turning into liquid water. Inside bubbles of boiling water is
water vapor – molecules of water that have a lot more energy so they move more, take up more
space (remember gases are the least dense and are mostly empty space).
25. Sketch a complete cooling curve and label the parts same as above in 2 - 4.
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Energy calculations
First, before you do any math, you should sketch a temperature-time curve so that you can focus
on what changes are taking place.
26. On the graph below sketch the curve that describes the following:
Initial state: 150 g solid water at –10 ˚C
Final state: 150 g liquid water at 0˚C
====================================================================
27. On the graph below, sketch the curve that describes the following:
Initial state: 200 g liquid water at 40 ˚C
Final state: ALL of the water has boiled away at 100˚C
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Q = C x m x ΔT (when Eth changes)
Q = H x m (when Eph changes)
Energy constants (H2O)
334 J/g
Heat of fusion (melting or freezing) Hf
2260 J/g
Heat of vaporization (evaporating or condensing) Hv
2.1 J/g˚C
Heat capacity (C) of solid water
4.18 J/g˚C
Heat capacity (C) of liquid water
Determine the amount of energy needed to complete the above. Be sure to use the energy
constants below and the heat capacity equation.
8.
What quantity of heat is needed to evaporate completely 250 grams of water at 24 degrees
Celsius? Sketch a time temperature curve, make the calculation.
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1. Sketch figure 2.8.
For each of the diagrams below, describe the contents of each cell using the terms element compound,
mixture, solid, liquid and gas
1.
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6.
Identify the separation techniques pictured below. Which technique would be useful to separate a
mixture of sand and
salt? Of
salt and water?
7.
Below left is a 2-D array that represents an ionic lattice. At right is a 2-D array that represents a
molecular solid. In what ways are they similar? In what ways are they different?
10. Below is a group of the inner cores of a piece of metal foil. Sketch in where
you would expect to find the mobile negative charges if a top (+) tape were brought to the left of the foil.
Explain your diagram.
11. Identify the following as physical or chemical changes:
a. cutting paper - _____________________
b. boiling water - _____________________
c. burning propane - __________________
d. iron rusting - ______________________
e. burning steel wool- _________________
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f.
dissolving salt in water- ____________
13. List some physical properties and chemical properties of hydrogen gas based on the electrolysis of
water demo.
14. Is electrolysis of water a physical or chemical change? Explain why. Include particle diagrams to aide
your explanation.
1.
For the following scientists, describe the atomic model they proposed and their
to the progression of the atomic theory.
a.
Dalton
b.
J.J. Thomson
contributions
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c.
2.
E. Rutherford
Complete the following table from page 111 in your textbook:
Properties of Subatomic Particles
Particle
3.
Symbol
Relative Charge
Relative Mass
a.
Which subatomic particles are in the nucleus?
b.
Which subatomic particles have the same mass?
Actual Mass
Complete the following table:
Symbol
Atomic Number
54Mn
35
Protons
2
19
Neutrons
2
20
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Electrons
Mass Number
18
79
4. How many protons are in the nucleus of a copper atom?
5. Has a strontium 2+ ion (Sr2+) lost or gained electrons?
6.
What is the symbol and charge of chlorine when it becomes an ion?
7. The relative abundances of the isotopes of Element X in nature are:
mass number = 204; 1.37%
mass number = 206; 26.26%
mass number = 207; 20.82%
mass number = 208; 51.55%
Calculate the average molar mass and identify the element.
9.
Sketch an orbital spin diagram for the following atoms:

C

Ar
What useful information is conveyed in an orbital spin diagram?
10.
Write the electron configuration of each element, use shorthand notation for elements with atomic
number greater than 36:
a.
hydrogen
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b.
barium
c.
krypton
h.
sulfur
i.
radon
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