Chemistry 101 Final Exam

What is the formula for aluminum sulfate?

Al2(SO4)3

Which two have the same mass?

Atoms 2 & 4

The box for an element from the periodic table is shown. Which is the atomic number?

B

Place these five elements in order of electronegativity, with the highest electronegativity first.

B D C E A

The box for an element from the periodic table is shown. Which is the atomic mass?

D

This man was one of the first with the theory of the atom, but his ideas have been revised over time

Dalton

What is the Lewis structure of methanethiol, CH3SH?

H | .. H - C - S - H | .. H

The ionic compound magnesium hydroxide can be found in antacid tablets. What is the formula of magnesium hydroxide?

Mg(OH)2

What is the formula for dinitrogen trioxide?

N2O3

Which scientist described a positively charged core ("nucleus") in the middle of a lot of empty space?

Rutherford

What is the formula of the compound sulfur trioxide?

SO3

Which properly represents the Lewis structure of hydrogen sulfide, H2S?

.. H - S - H ..

What is the correct Lewis structure for hydrogen chloride, HCl?

.. H-Cl: ..

How many moles of LiF are present in 10.37 g?

0.3998 mol

Which is the number of protons in 56/26 Fe

26

How many molecules of water are present in a 5.64 mole sample of water?

3.40 x 10^24 molecules

What is the average atomic mass of this element? Isotope Mass (amu) % Abundance Phosphorus-29 29 5% Phosphorus-31 31 71% Phosphorus-32 32 24%

31.1 amu

How many neutrons are present in an atom of the isotope of Lithium-7?

4

What is the mass of 0.150 mole sample of sulfur?

4.81 g

Which is the sum of these values, to four significant digits

41.00

Which is the number of neutrons in 80/35 Br?

45

How many significant digits are in the value 0.0050340

5

Which is the correct measurement for the location marked by the arrow?

52

How many significant digits are in the value 530,405,000?

6

How many significant figures does the number 5.06304 x 10^4 contain?

6

What is the number 0.0062985632 written in scientific notation to three significant figures?

6.30 x 10^-3

Which value has only 4 significant digits

6.930

A pure sample of bromine was vaporized and injected into a mass spectrometer. The mass value for one isotope is Br with a mass of 78.918 amu at 51.5% abundance and another isotope of Br with a mass of 81.0 amu at 48.9%. What is the average atomic mass?

80.3 amu .515 x 78.918 = 40.64277 .489 x 81.0 = 39.609 = 80.25177 -> 80.3

Which is the correct symbol for the atom with 42 protons and 49 neutrons?

91 42 Mo

Americium-241 is an isotope used in smoke detectors. What is the composition of a neutral atom of Americium-241?

95 protons, 146 neutrons, 95 electrons

Name the compound CF4.

carbon tetrafluoride

When hydrogen and chlorine gases are mixed, hydrogen chloride is produced. Hydrogen chloride (HCl) is classified as what type of matter?

compound

What does the mass number minus the atomic number represent

number of neutrons

This studies carbon and its interactions with other elements.

organic chemistry

How is the reaction shown below best classified? Ca(s) + 2HCl(aq) -> CaCl2(g) + H2(g)

single-replacement

How is the reaction shown below best classified? 2NaCl(s) + F2(g) -> 2NaF(s) + Cl2(g)

single-replacement

What is the name of the ionic compound with the formula Na3PO4?

sodium phosphate

Which is the term used for the measurement of the average kinetic energy of the particles of a substance?

temperature

The identity of an atom is determined by which of the following?

the number of protons it has

What is always true about a neutral atom?

there is an equal number of protons and electrons

Which type of molecular shape is shown by this molecule?

trigonal bipyramidal

Which type of molecular shape is shown by this molecule?

trigonal planar

Which physical property of an astronaut will change depending on whether he or she is on Earth or in orbit?

weight

Name the compound Zn3(PO4)2

zinc phosphate

What term is used for the elements straddling the "staircase" boundary between the metals and nonmetals?

metalloids

The equation A+BX->AX+B is the general equation for a

single-displacement reaction

How may electrons are present in an atom of silicon?

14

What is the mass of 4.00 moles of helium, the gas commonly used to fill party balloons and lighter-than-air ships?

16.0 g

Given that helium has an isotope He-4, how many electrons does an atom of helium contain?

2

The chemical equation below is unbalanced. What is the coefficient of water when the equation is balanced? Mg(OH)2(s) + HCl(g) -> MgCl2(s) + H2O(l)

2

What are the correct coefficients when this equation is balanced? K+Br2->KBr

2,1,2

How many moles of NO2 are present in 114.95 g?

2.498 mol

What is the formula of the ionic compound formed when calcium and nitrogen combine?

Ca3 N2

What is the formula for the compound formed by calcium ions and chloride ions?

CaCl2

Which scientist described the existence of the neutron?

Chadwick

A measurement of 5.685 x 10^-6 is equivalent to 0.0000005685.

False

In most line graphs, the dependent variable is placed along the X-axis.

False

The thermometer shown is measuring the temperature in Fahrenheit.

False

What is the formula of Iron (III) bromide?

FeBr3

What is the name of Fe2(SO4)3

Iron III Sulfate

What is the proper name of Mg(CN)2?

Magnesium cyanide

In nature, the element neon exists as three different isotopes: Ne-20, Ne-21, and Ne-22. Which isotope would be the most abundant in a sample?

Ne-22

Which of the following is a nonmetal?

P

What is the correct formula of diphosphorus pentoxide?

P2O5

29 +4 Si 14

P=14 , N=15 , E=10

15 -3 N 7

P=7 , N=8 , E=10

Calculate the number of protons, electrons, and neutrons in an atom of the element Pb with mass number 207 and atomic number 82.

P=82 , N=125 , E=82

Which of the following has the highest atomic radius?

Rb

Who discovered that cathode rays consists of a stream of negative particles (electron)?

Thomson

Write the short hand electronic configuration for Copper.

[Ar] 4s^2 3d^2

How is the reaction shown below best classified? 2HgO(s) -> 2Hg(l) + O2(g)

decomposition

What is the proper name for N2O5.

dinitrogen pentoxide

Name the compound N2O3

dinitrogen trioxide

Classify the following reaction: H2SO4(aq) + 2KOH(aq) -> K2SO4(aq) + 2H2O(aq)

double replacement

What kind(s) of particles can be found outside the nucleus of an atom?

electrons

Which of the following is a chemical property?

flammability

A covalent bond is

formed when two nonmetals share a pair of electrons

In which state does matter have indefinite shape and indefinite volume?

gas

Which of the following is a characteristic of ionic bonds?

high melting points

Name the compound Fe(NO3)2.

iron (II) nitrate

What term is used to describe atoms of the same element that have different masses?

isotopes

A student records the measurement 4.8m. What type of measurement was made?

length

The drug "lithium" is often prescribed to treat mental illness. It is not the element lithium, but the ionic compound Li2CO3, that is actually administered. What is the name of this compound?

lithium carbonate

Which of the following is a characteristic of covalent bonds?

low melting points

Which of the following terms is defined as anything that has mass and takes up space?

matter

Which statement best describes the Law of Conservation of Mass?

matter is neither gained or lost in a chemical reaction

Which combination of atoms is most likely to form an ionic compound if they are allowed to react with each other?

metal and nonmetal

The following is the configuration for which of the following element: 1s^1 2s^2 2p63s^2 3p^3

phosphorus

What type of change alters the appearance, but not the composition or identity of the substance undergoing the change?

physical

Name the compound KClO3.

potassium chlorate

What kind of energy is stored as the result of position or composition?

potential energy

The accepted value is 15.63. Which correctly describes this student's experimental data?

precise but not accurate

What method is used by scientists as the systematic approach to the discovery of new information?

scientific method

Identify the element containing 34 protons.

selenium

A covalent bond involves which of the following?

sharing of electrons between two atoms

An object has a mass of 26.94 grams and a volume of 2.568cm^3. What material is it likely to be made of?

silver