WorksheetsChemistry Midterm Review
Total questions: 50
Worksheet time: 26mins
.In 1808, John Dalton proposed his atomic theory. Why is Dalton’s proposal still considered a theory?
Atoms are too small to test
Scientists are still testing it
there is no experimental evidence to support it
all his hypotheses about atoms have proven false
How did Henry G. J. Moseley change the periodic table created by Dmitri Mendeleev?
He added all the period 6 elements
He added a new column for the group 1 metal
he ordered the elements using their atomic numbers
he ordered all the elements in blocks of metals and non-metals
A solid had dimensions 6cmx5cmx3cm and a density of 2.1g/cm (cubed). Whats the mass of the solid?
189g
0.02g
42.8g
90g
Which statement is always true for a compound?
It is homologous
It contains only 1 element
It decomposes phisically
Its chemical composition varies
What is the name to anything that take up space and has mass?
Compound
Mixture
Matter
Substance
Which set contains ONLY physical properties
Color, Taste, Ability to Rust
boiling point, solubility, viscosity
density, flammability, freezing point
melting point, odor, reactivity to light
What is the Volume in mL of a sample of glycerol with a density of 1.20 g/mL and a mass of 43.7g?
36.4 mL
52 mL
0.03 mL
18mL
Which statement describes a property of all the group 14 elements?
they are all metals
all non metals
form ions with 2- charge
2 valance electrons in P orbital
At standard atmospheric pressure, Nick heats a sample of caffenine. At 178 degrees celsius, solid converts directly to a gas. Name of phase change?
Condensation
Sublimation
Evaporation
Freezing
Elements in order of increasing electronegativity
Be, B, C, F
Br, Se, Ga, K
N, P, As, Sb
O, Ge, In, Hg
Whats the electron configuration of the chromium (Cr) ion in chromium trioxide?
Ar
Ar3d3
Ar 4s2 3d1
Ar 4s2 3d4
What is the name of PO4−3
phosphate ion
dihydrogen phosphate ion
phosphorus tetraoxide ion
phosphite ion
What is the Name of NH4Br ?
nitrogen hydrogen bromide
ammonium bromate
ammonium bromide
nitrogen tetra hydrogen bromide
How many hydrogens are in CH3COOH
3
1
4
2
. Cobalt-60(60 27Co) is an isotope of an elemental Co. How many protons and neutrons are in the nucleus of a neutral 60 27Co atom?
27 protons and 33 neutrons
27 protons and 60 neutrons
33 protons and 27 neutrons
33 protons and 60 neutrons
Which property of ionic compounds can a chemist use to differentiate between ALL ionic and covalent compounds?
they are insoluble in water
they have low melting points
they are solids at room temperature
they conduct electricity when they melt
Whats the correct chemical formula for copper (1) sulfate?
Cu2SO3
Cu2SO4
CuSO3
CuSO
In Magnesium nitride (Mg3N2), nitrogen (N) has an oxidation number of -3. What is the electron configuration of the N3- ion?
. [He] 2s1
. [He] 2s2
. [He] 2s2 2p3
. [He] 2s2 2p6
A substance with a density of 3g/cm3 has a volume of 2 cm3 . What is its mass?
1.5g
6g
1.33g
it has no mass
Dr. Forbes, a visiting chemistry professor from a local university, performed a demonstration in the high school chemistry lab. Behind a protective shield in the fume hood, she carefully added a small piece of sodium (Na) to a beaker of water, and a very exothermic reaction occurred. Which property of Na would best explain this result?
Small density
Large atomic radius
low first ionization energy
high electronegativity
Whats the Chemical symbol for cobalt?
Cl
Ca
C
Co
Which element has this electron configuration?
1s2 2s2 2p6 3s2 3p4
Nitrogen (N)
Oxygen (O)
Phosphorus (P)
Sulfur (S)
Using the valence-shell electron-pair repulsion (VSEPR) theory, what is the geometry of boron trichloride (BCl3)?
Trigonal Planar
Bent
T-Shaped
Trigonal Pyramidal
What type of solid is Cesium bromide CsBr
ionic
metallic
molecular
network
What must be true for a substance to be called potassium?
must have 19 protons
must have 19 neutrons
must have 19 electrons
must have a mass of 19
Which set of electrons has the same valence electron configuration as germanium (Ge)?
A. Aluminum(Al), antimony(Sb), and polonium(Po)
Arsenic(As), bromine (Br), and Gallium (Ga)
Carbon (C), lead (Pb), and silicon (Si)
D. Indium(In), oxygen (O), and phosphorus(P)
When Alex distills Substance X, he obtains 3 different pure liquids with boiling points of 150°C, 250°C, and 350°C. How would Alex classify substance X?
element
compound
mixture
molecule
Which statement is an accurate description of Period 3 in the periodic table?
has elements with the same number of protons
elements with the same number of valance electrons
It contains elements with outermost protons in the same principal energy level.
D. It contains elements with the outermost electrons in the same principal energy level
Correct formula for iron (III) sulfide
FeS
Fe3S
Fe2S3
Fe2S
Using the valence-shell electron-pair repulsion (VSEPR) theory, what is the geometry of the nitrate ion (NO3 - )?
Trigonal Planar
Trigonal Pyramidal
T-Shaped
Trigonal bipyramidal
. In a famous experiment, scientists bombarded a very thin gold (Au) foil with positively charged alpha particles. They found that most of the alpha particles passed right through the Au foil. However, a few of the alpha particles were deflected or bounced back toward the source. How did these scientists explain their results?
negative charges are spread throughout the atom
negative charges are located in the tiny nucleus of an atom
positive charges were spread throughout the atom
positive charges are located inside the tiny nucleus of an atom
At 25°C, germanium (II) chloride (GeCl2) rapidly reacts with chlorine (Cl2) to produce germanium (IV) chloride (GeCl4) according to the following equation: GeCl2 + Cl2 ® GeCl4 According to the law of conservation of mass, which statement correctly describes this reaction?
the sum of the masses f GeCl2 and Cl2 equals the mass of Ge
the sum of the masses of Cl2 GeCl4 equals the mass GeCl2
The mass of GeCl2 is greater than the mass of the GeCl4
The mass of Cl2 is greater than the mass of the GeCl4
. Hypothetical Element Q has 3 isotopes with the relative abundances shown in this table. What is the average atomic mass of Element Q?
56.62
56.17
55.97
55.74
What is the Lewis dot structure of arsenic triiodide (AsI3)?
. Using the valence-shell electron-pair repulsion (VSEPR) theory, what is the molecular geometry of sulfur dichloride (SCl2)?
trigonal planar
tetrahedral
linear
bent
The electron configuration of a neutral arsenic (As) atom?
. [Ar] 4s2 3d10 4p3
C. [Ar] 4s2 4d10 4p3
B. [Ar] 4s2 3d10 4p4
D. [Ar] 4s2 4d10 4p4
What is the orbital diagram for the outermost electrons in the ruthenium (III) ion (Ru3+)?
A
B
C
D
What compound is the most polar?
H2O
CO2
CH4
SiCl4
For a homework assignment, Sarah must determine which ground state element has the most significant number of unpaired electrons. Which element is her correct answer?
Arsenic (As)
Germanium (Ge)
Iron (Fe)
Selenium (Se)
Which statement correctly describes the melting point of a solid?
. The particles in the solid lose enough kinetic energy to overcome the interactions preventing them from approaching one another
C. The particles in the solid gain enough kinetic energy to overcome the interactions preventing them from approaching one another.
B. The particles in the solid lose enough kinetic energy to overcome the interactions holding them in an organized pattern.
D. The particles in the solid gain enough kinetic energy to overcome the interactions holding them in an organized pattern.
As part of a demonstration, the teacher uses a hot plate to heat three liquids in beakers to boiling. Liquid A is water, Liquid B is ethanol, and Liquid C is an aqueous copper (II) sulfate solution. The students observe the boiling liquids and note that, in each beaker, bubbles form on the bottom and side surfaces of the beaker and then rise to the liquids surface. What do the bubbles forming in Liquid B during boiling contain?
Air
Ethanol Vapor
hydrogen and oxygen gas
water vapor
What's the chemical formula for calcium cyanide?
CaCN
CaCN2
Ca(CN)2
Ca(CN)4
. What is the orbital diagram for the outermost electrons in a neutral chlorine (Cl) atom?
A 1
B 2
C 3
D 4
While researching the ozone (O3) layer surrounding the Earth, Ling found that chemists represent the Lewis dot structure of O3 using 2 resonance forms that obey the octet rule. Which structure is one of the resonance structures of O3?
. What is the correct balanced chemical equation for the complete combustion of octane?
C8H18(I)+4O2(g) -->8CO(g)+9H2(g)
C8H18(I)+8O2(g)-->8CO2(g)+9H20(g)
2C8H18(I)+17O2(g)-->16CO(g)+18H20(g)
2C8H18(I)+25O2(g)-->16CO2(g)+18H20(g)
Fluorine gas reacts with aqueous iron (II) iodide to produce aqueous iron (II) fluoride and iodine liquid. What is the balanced chemical equation for this reaction?
A. F2(g) + FeI2(aq) --> FeF2(aq) + I2(l)
C. 2 F(g) + FeI2(aq)--> FeF2(aq) + 2 I(l)
B. F2(g) + 2Fe2I(aq) --> 2Fe2F(aq) + I2(l)
D. F(g) + Fe2I(aq) --> Fe2F(aq) + I(l)
. What is the balanced chemical equation for the reaction of solid aluminum hydroxide with aqueous hydrochloric acid?
. Al(OH)2(s) + 2 HCl(aq) --> AlCl2(aq) + H2O(l)
B. Al(OH)2(s) + 2 HCl(aq) --> AlCl2(aq) + 2 H2O(l)
C. Al(OH)3(s) + 3 HCl(aq) --> AlCl3(aq) + 3 H2O(l)
D. Al(OH)3(s) + 3 HCl(aq)--> AlCl3(aq) + 4 H2O(l)
In step 1, ammonia (NH3) reacts with acetic acid (C2H4O2) to produce ammonium acetate (NH4C2H3O2). In step 2, at high temperatures, NH4C2H3O2 converts to acetamide (C2H5NO) and water (H2O). Classify the chemical reaction in step 1 and step 2.
synthesis and decomposition
synthesis and single replacement
decomposition and single replacement
double replacement and single replacement
At very high temperatures, aluminum metal reacts with chromium (III) oxide to produce aluminum oxide and chromium metal. What is the balanced chemical equation for this reaction?
2 Al(s) + CrO3(s) --> Al2O3(s) + Cr(l)
C. 3 Al(s) + Cr3O2(s) __> Al2O3(s) + 3 Cr(l
B. 2 Al(s) + Cr2O3(s) --> Al2O3(s) + 2 Cr(l)
D. 6 Al(s) + Cr3O4(s) --> 2 Al2O3(s) + 3 Cr(l)
. An irregular solid with a mass of 6.253 g is placed in a graduated cylinder with 6.01 mL of water. The volume in the graduated cylinder increases to 8.31 mL. Using the correct number of significant figures, what is the density of the irregular solid?
2.719 g/ml
2.72 g/ml
2.7 g/ml
3 g/ml
