Mr. Stone
Name:________________
Chemistry I
Chemistry I Midterm Celebration of Knowledge
1.
a.
b.
c.
d.
2.
a.
b.
c.
d.
3.
a.
b.
c.
d.
4.
a.
b.
c.
d.
5.
Which branch of chemistry studies Carbon
compounds?
Organic chemistry
Inorganic chemistry
Analytical chemistry
Physical chemistry
In science, a theory is best characterized as
a guess
a tentative explanation that requires more
evidence to be confirmed
an extremely well confirmed explanation that
unifies a wide range of observations
a generalization of past observations
Two different elements chemically bonded
together are known as a
compound
mixture
solution
acid
The chemical bond where atoms share electrons
is a
Hydrogen bond
Ionic bond
Van der Waal’s attraction
Covalent bond
a.
b.
c.
d.
Which kind of subatomic particles are found in
the nucleus of an atom?
Protons
Neutrons
Electrons
Both a and b
6.
a.
b.
c.
d.
While protons have positive charge, neutrons
Also have positive charge
Have negative charge
Have no charge
Can have positive or negative charge
7.
a.
b.
c.
d.
Ions are formed when atoms
Gain electrons
Lose electrons
Gain neutrons
Either a or b
8.
a.
b.
c.
d.
Which one is a pure substance?
Campbell’s chunky soup
Lemonade
Air
Baking soda
9.
a.
b.
c.
d.
Which one is an element?
Fire
Earth
Water
Arsenic
10. Tap water contains dissolved ions, like Mg2+ and
Ca2+. Therefore, tap water is best classified as a
a. Pure substance
b. Heterogeneous mixture
c. Solution
d. Suspension
11. Distilled water does not contained dissolved
ions. Therefore, distilled water is best classified
as a
a. Pure substance
b. Heterogeneous mixture
c. Solution
d. Suspension
12. Which of the following is an example of a
physical change?
a. A precipitation reaction
b. Bubbling CO2 gas from a mixture of baking soda
and vinegar
c. The rapid drop in temperature that occurs when
barium hydroxide is mixed with ammonium
chloride and ammonia gas is released (smelly
stuff!)
d. NaCl dissolving in water
13. Which of the following is an example of a
chemical change?
a. NaCl dissolving in water
b. Na exploding in water
c. Water changing from a liquid into a gas
d. A distillation
14. For most pure substances, which is the correct
order, going from most dense to least dense?
a. Solid, gas, liquid
b. Solid, liquid, gas
c. Liquid, solid, gas
d. Liquid, gas, solid
15. For water, which is the correct order, going from
most dense to least dense?
a. Solid, gas, liquid
b. Solid, liquid, gas
c. Liquid, solid, gas
d. Liquid, gas, solid
16.
a.
b.
c.
d.
Which is a quantitative measurement?
Color
Smell
Density
Shape
17.
a.
b.
c.
d.
2 x 1017 + 4 × 1017 =
6 × 1034
6 × 1017
6 × 100
6 × 10289
18.
a.
b.
c.
d.
(6 x 106) ÷ (3 × 108) =
9 × 1014
2 × 102
2 × 10-2
3 × 10-2
19.
a.
b.
c.
d.
In scientific measurement, accuracy is
The repeatability of a measurement
The number of decimals you need to write down
How close you are to the actual value
Not important when writing the molar mass in a
% composition problem
20.
a.
b.
c.
d.
In scientific measurement, precision is
Basically the same thing as accuracy
The repeatability of a measurement
How close you are to the actual value
Only important if you are throwing darts at a dart
board
21.
a.
b.
c.
d.
How many significant figures are in 50.26 × 10 4?
3
4
unlimited
6
22.
a.
b.
c.
d.
How many significant figures are in 0.00034?
unlimited
2
5
6
23.
a.
b.
c.
d.
How many significant figures are in 5.00?
1
2
3
Unlimited
24. How many significant figures are in 1.00cm =
10.0mm?
a. 1
b. 2
c. 3
d. Unlimited
25.
a.
b.
c.
d.
With significant figures, 5.2 – 0.001 =
5.199
5.19
5.2
5
26.
a.
b.
c.
d.
With significant figures, 4.78 ÷ 2.32 – 1.0 =
1.06
1.1
3.62
3.6
27.
a.
b.
c.
d.
With significant figures, 8.452 + 1.920 × 1.31 =
13.6
13.59
10.0
10.97
28.
a.
b.
c.
d.
54.0mg =
5.4 × 10-4 kg
5.4 × 10-5 kg
5.4 × 10-6 kg
5.4 × 10-7 kg
29. What is the density of a wooden block with the
dimensions 4.0cm × 2.0cm × 2.0cm, and a mass
of 8.0g?
a. 2.0cm3/g
b. 5.0g/cm3
c. 2.0g/mL
d. 0.5g/mL
30. The specific gravity of a solution with a density
of 1.2g/mL = ________________
31. Silver has a density of 10.49g/cm3. What is its
density in kg/m3?
a. 104.90 kg/m3
b. 1049.0 kg/m3
c. 10490 kg/m3
d. 104900 kg/m3
32. Dalton’s atomic theory says that
a. Elements are composed of different isotopes
b. Elements are made of atoms in the same way that
atoms are made of protons, neutrons, and
electrons
c. All samples of an element are identical to each
other
d. Atoms are made of protons, neutrons, and
electrons
38. Which of the following elements can make more
than one cation?
a. Na
b. Mg
c. Zn
d. Fe
39.
a.
b.
c.
d.
What is the correct name for AlN?
Aluminum nitrate
Aluminum nitrioxidous
Aluminum nitride
Sulfur nitrogen
40. What is the correct way to go from the volume of
a gas at STP to a mole?
a. Multiply by 1.00mol/22.4L
b. Multiply by 22.4L/1.00mol
c. Divide by molar mass/1.00mol
d. Divide by 1.00mol/22.4L
33.
a.
b.
c.
d.
Which element has the atomic number 6?
Boron
Lithium
Nitrogen
Carbon
41.
a.
b.
c.
d.
Which of the following is a binary compound?
Hydrogen sulfide
Hydrogen sulfate
Ammonium sulfide
Ammonium sulfate
34.
a.
b.
c.
d.
How did Mendeleev arrange the periodic table?
By increasing atomic mass
By increasing atomic number
By increasing mass number
By increasing boiling point
42.
a.
b.
c.
d.
What is the symbol for manganese?
Ar
Mo
Mn
Mg
43.
a.
b.
c.
d.
The polyatomic ion MnO4- is named
Permanganate
Permangoxide
Permangadioxide
Mangoxide
44.
a.
b.
c.
d.
The compound P4S7 would be named
Phosphorous sulfide
Pentaphosphorous hexasulfide
Tetraphosphorous heptasulfide
Tetraphosphorous heptasulfur
35. Which group would probably contain an element
that conducts electricity?
a. Halogens
b. Noble gasses
c. Alkali earth metals
d. Chalcogens (like oxygen and sulfur)
36.
a.
b.
c.
d.
Which element has 5 valence electrons?
Boron
Carbon
Nitrogen
Oxygen
37.
a.
b.
c.
d.
Ionic bonds occur between
A metal and a non-metal
Two metals
Two non-metals
Two cations
45. What is the correct formula for Mercury(I)
oxide?
a. HgO
b. Hg2O2
c. Hg2O
d. HgO2
46.
a.
b.
c.
d.
Name the compound HCl
Monohydrogen monochloride
Hydrochloric acid
Hydrogchlorous acid
Chlorohydric acid
47. By mass a compound is 33% C, 44% O, and
23% H. If you have 100g of the compound, how
many grams are Carbon?__________________
48.
a.
b.
c.
d.
What is the empirical formula for C6H12?
C4H8
CH2
C3H6
C2H4
49.
a.
b.
c.
d.
What is STP?
0ºC and 1atm
20 ºC and 1atm
0 ºC and 0atm
20 ºC and 0atm
50. How many moles of carbon are in 1 mole of
CO2?
a. 6.022 × 1023
b. 12.011
c. 1
d. 22.4
Lab Practical—Show all of your work and follow the conventions of significant figures (10 points):
How many grams of NaCl are in the cup?
Worked problems—Show all of your work and follow the conventions of significant figures (10 points each):
1.
How many molecules are there in 5.45 × 102 g of benzoic acid (C6H7O2)?
2.
What is the empirical formula of a compound that is 25.9% N and 74.1% O?
3.
Suppose there were an element with an average atomic mass of 54.6amu. It has two isotopes, one that has
53amu, and another with 55amu. What are the % abundances of these isotopes?
4.
How many mL is 0.75mol of N2 gas at STP?
Bonus: How many centuries would it take to count to a mole if you counted by 1 every second? (10 points)