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Final Exam Review
Chemistry – First Semester
“Matter is made up of atoms. Atoms have tiny positive centers containing protons and neutrons.”
The above statement is a/an
A. inferenceB. hypothesisC. theoryD. observation
Answer: C
In order to become a theory, a hypothesis should beA. obviously accepted by most people.B. a fully functional experiment.C. in alignment with past theories.D. repeatedly confirmed by experimentation
Answer: D
What is the density of a substance which has a volume of 100.0 mL and a mass of 85.5 g?
Answer: 0.855 g/mL
How many significant digits does this measurement have?
95.50 mL
Answer: 4
Calculate the % error of a measurement (0.90 g/mL) if the true value is 1.0 g/mL.
Answer: 10%
Which of these statements is NOT true about matter and energy?
A. All matter possesses energy.B. Matter can be changed into energy and energy can be
changed into matter.C. Energy can only be transferred from one sample of
matter to another when they are in direct contact with one another.
D. The total amount of matter and energy in the universe remains the same; they just change from one form to another.
Answer: C
Which of these is an exothermic process?A. Melting of iceB. Combustion (burning) of gasolineC. PhotosynthesisD. Evaporation of water
Answer: B
An endothermic reaction A. releases energy to the surroundings.B. causes a temperature increase in its
surroundings.C. absorbs energy from its surroundings.D. produces substances that have a lesser
energy than the starting materials.Answer: C
Which is true about metals?A. They are found on the right side of the periodic table.B. They are poor conductors .C. They have higher densities compared to non-metals.D. Most of them are liquids and gases at room
temperature.
Answer: C
The nucleus of an atomA. is negatively-chargedB. accounts for most of the atom’s massC. occupies most of the atom’s volumeD. contains electrons and protons
Answer: B
Give the number of protons, electrons and neutrons of 15
8O.
Answer: electrons- 8, protons- 8, neutron-7
Which of these is NOT true of the atom?A. It may be positively or negatively-
charged.B. It contains the same number of protons
and electrons.C. It is mostly empty space.D. It has a very dense center.
Answer: A
Isotopes of the same element always have the sameA. atomic numberB. mass numberC. atomic massD. number of neutrons
Answer: A
Some isotopes easily break down and emit radiation. Which type of radiation is the least penetrating?
A. betaB. alphaC. X-rayD. gamma
Answer: B
When a metal is heated in a flame, the flame turns a distinctive color. This information can be applied in the study of stars because
A. star color tells us how far it is from the earth.B. the color of the star tells us how big it is.C. the color of the star tell us how old it is.D. the color spectra of a star show which elements are
present in it.
Answer: D
How many valence electrons does nitrogen have?
Answer: 5
Draw the Lewis Dot diagram of carbon
Answer: C
Which element do you expect to have the same valence electrons as carbon?
A. calciumB. ironC. chlorineD. silicon
Answer: D
Write the electron configuration of potassium.
Answer: 1s2 2s2 2p6 3s2 3p6 4s1
Which of these is a halogen?A. heliumB. carbonC. lithiumD. iodine
Answer: D
To which family does the element krypton belong?
A. Alkali metalB. Alkaline-earth metalC. Transition MetalD. Noble gases
Answer: D
Which of these is true of noble gases?A. They have 8 valence electrons except for
helium.B. They belong to Group 2A.C. They easily form bonds with other
elements.D. They have very low ionization energies.
Answer: A
In general, how do atomic masses change throughout the periodic table of elements?
A. They increase from left to right and top to bottom.
B. They increase from left to right and bottom to top.
C. They increase from right to left and top to bottom.
D. They increase from right to left and bottom to top.
Answer: A
Why is cobalt (Co) placed before nickel (Ni) on the periodic table even though its atomic mass is higher than nickel’s?
A. Cobalt has more electrons.B. Nickel has a higher density.C. Cobalt was discovered first.D. Nickel has one more proton.
Answer: D
Which element is the least electronegative?A. NitrogenB. PhosphorusC. OxygenD. Sulfur
Answer: B
Which type of chemical bond exists between a metal and a non-metal?
Ionic
Answer: A
Metallic substances are usually good conductors of electricity because
A.of the loosely bonded electrons that move around the metal structure
B.of the closely packed atomsC.of the strong bonds that exist between atomsD.of the weak bonds that exist between atoms
Answer: A
Which of these is NOT an electrical conductor?
A. aluminumB. Alcohol (C2H5OH) solution
C. Potassium chloride (KCl) solutionD. Hydrochloric acid (HCl) solution
Answer: B
Which element can form long chains of atoms by forming single, double and triple bonds with itself?
A. oxygenB. nitrogenC. carbonD. hydrogen
Answer: C
What is the correct formula of sodium bromide?
A. NaBrB. Na2Br
C. NaBr2
D. Na2Br2
Answer: A
What is the chemical formula for sodium sulfate?
Na2SO4
What is the chemical formula for copper (II) nitrate?
Cu(NO3)2
Give the name of CaCl2
Calcium Chloride
Give the name of FeSO4
Iron (II) sulfate
What is the correct formula of sodium bromide?
A. NaBrB. Na2Br
C. NaBr2
D. Na2Br2
Answer: A
Which of these is an acid?H2SO4
KOHK2SO4
Answer: H2SO4
Which is a polar covalent bond?A. N-HB. As-HC. O-OD. Cl-Cl
A
Write the Lewis dot diagram of H2S.
H S H
How many non-bonding (unshared) pairs of electrons does sulfur have in
H2S?
2
How many non-bonding pairs does sulfur have in H2S?
2
What is the shape of the H2S molecule?
Bent
Is the H2S molecule polar or non-polar?
Polar
Which of these is a polar molecule?A. CO2
B. SF6
C. CH4
D. PCl3
D
Predict the shape of the NH3.
Trigonal Pyramidal
These pairs of atoms are covalently bonded. Arrange them according to increasing polarity.A. N-OB. Cl-FC. C-HD. C-Cl
C,D,A,B
Which of these is an alkene?A. C3H8
B. C4H8
C. C5H8
D. C6H14
B
B
NH3 + HCl → NH4Cl
How many grams of NH3 is needed to produce 25 g of NH4Cl?
8.0 g of NH3
