Chem101 Exam 1 Review Questions

How many unpaired electrons are there in a boron atom in its ground state?

1

How many unpaired electrons are there in a fluorine atom in its ground state?

1

How many liters (L) are there in 1 nanoliter (nL)?

1 * 10 ^-9

How many kiloliters (kL) are there in 1 microliter (μL)?

1 * 10^-9

How many millimeters (mm) are there in 1 megameter (Mm)?

1 * 10^9

Which of the following sets of numbers could be used to designate the principal energy levels (shells) in an atom? 1) -1, 0, 1, 2, 3 2) 1, 2, 3, 4, 5 3) 0, 1, 2, 3, 4 4) all of these

1, 2, 3, 4, 5

During its orbit, the Earth's minimum distance from the sun is approximately 148 million kilometers. What correctly represents this number in scientific notation?

1.48 * 10 ^8

Given the calculation: (2.33 × 10^7) × (6.7 × 10^5) = ?, what is the answer reported to the correct number of significant figures?

1.6 * 10^13

The area of Russia is approximately 17.1 million square miles. What represents this number in scientific notation?

1.7 * 10^7

The two most abundant naturally occurring isotopes of carbon are carbon-12 (98.90%, 12.000 amu) and carbon-13 (1.10%, 13.003 amu). What is the atomic weight of carbon, reported to the correct number of significant digits?

12.01 amu

The land surface area of the earth is approximately 1.49 × 108 km2. What is the correct way to write this in conventional notation?

149,000,000 km2

Given the calculation 5.63 + 2.302 - 3.1 = ?, how man sig figs should the answer have?

2

Given the calculation: 4.238 × 9.1 = ? how many sig figs should the answer have?

2

How many unpaired electrons are there in a carbon atom in its ground state?

2

Given the calculation: (3.83 × 10 ^-3) × (7.777 × 10^7) = ?, what is the answer reported to the correct number of significant figures?

2.98 *10^5

At the 2008 Olympics, the Jamaican runner Usain Bolt ran the 200-meter dash in world record time of 19.30 seconds. What is this speed in miles per hour? [1 mile = 1.609 km]

23.2 mph

How many unpaired electrons are there in a nitrogen atom in its ground state?

3

What Celsius temperature is the same as 86.0°F?

30.0°C

How many neutrons are present in a boron-10 atom?

5

Given the calculation: (12.02 × 10^23)/22.00 = ?, what is the answer reported to the correct number of significant figures?

5.464 * 10^22

What is the mass number of an atom that is made up of 27 protons, 32 neutrons, and 27 electrons?

59

What is the mass number of an atom that is made up of 38 protons, 49 neutrons, and 38 electrons?

87

Which of the following statements describes a compound? 1) a compound obeys the law of constant composition 2) a compound is a pure substance 3) a compound is both 4) a compound is neither

a compound is both

Which element is currently used to define the atomic mass unit?

carbon-12

which of the following is not a chemical change? 1) burning of paper 2) curdling of milk 3) evaporation of river water 4) rusting of an iron statue

evaporation of river water

What are the vertical columns of the periodic table called?

families

When a sample of a particular solid is examined under a microscope, clearly distinguishable black and yellow regions are observed. Which type of matter is this sample?

heterogenous mixture

Zinc can be mixed in differing amounts with copper to form an alloy called brass. Which of the following is brass an example of? 1) compound 2) homogenous mixture 3) element 4) heterogenous mixture

homogenous mixture

Which is the only nonmetal to appear on the left side of the periodic table?

hydrogen

Which of the following sets of elements is not included in the main body of the periodic table and is shown separately at the bottom?

inner transition elements

Which of the following is true of the atomic weight of an element? 1) it is a weighted average obtained from the weights and abundances of isotopes 2) it is the weight of the heaviest isotope 3) it is the weight of the most abundant isotope 4) it is the weight of the lightest isotope

it is a weighted average obtained from the weights and abundances of isotopes

What are the elements in the "A" columns of the periodic table called?

main group elements

the total number of protons and neutrons in the nucleus of an atom

mass number

Which of the following represents a physical change? 1) burning of fuel oil 2) melting of ice 3) both 4) neither

melting of ice

Which of the following statements is true of neutrons? 1) neutrons carry a positive charge 2) neutrons do not have mass 3) neutrons carry a negative charge 4) neutrons do not carry an electrical charge

neutrons do not carry an electrical charge

At what temperature do the temperatures on the Celsius and Kelvin scales have the same numerical value?

no value

Which of the following statements correctly describes an electron? 1) on the scale of subatomic particles, it is massive and has a +1 charge 2) on the scale of subatomic particles, it is massive and has a -1 charge 3) on the scale of subatomic particles, it is light and has a -1 charge 4) on the scale of subatomic particles, it is light and has a +1 charge

on the scale of subatomic particles, it is light and has a -1 charge

What are the horizontal rows of the periodic table called?

periods

If we consider the elements C, N, and O, which types of orbitals do these elements use in bonding?

s and p

Which of the following represents a physical change? 1) stretching of silverware 2) tarnishing of silver 3) both 4) neither

stretching of silverware

Which of the following is not an example of matter? 1) sunlight coming through the window 2) the blood in your arteries 3) the air in your lungs 4) none; they're all matter

sunlight coming through the window

Which of the following is not a physical property of copper? 1) characteristic color 2) density 3) electrical conductivity 4) tarnishing of copper

tarnishing of copper

which of the following is an example of matter? 1) the air you breathe 2) the sound of thunder 3) the light of a flame 4) none of the above

the air you breathe

Which of the following is true when comparing two electrons that are in different shells of an atom? 1) the electron in the higher-numbered shell is closer to the nucleus and is easier to remove 2) the electron is the higher-numbered shell is closer to the nucleus and is harder to remove 3) the electron in the higher-numbered shell is farther from the nucleus and is harder to remove 4) the electron in the higher-numbered shell is farther from the nucleus and is easier to remove

the electron in the higher-numbered shell is farther from the nucleus and is easier to remove

How are electrons distributed among orbitals of equal energy? 1) the electrons will occupy different orbitals and have like spins 2) the electrons will occupy different orbitals and have opposite spins 3) the electrons will occupy the same orbital rather than separate orbitals and have like spins 4) the electrons will occupy the same orbital rather than separate orbitals and have opposite spins

the electrons will occupy different orbitals and have like spins

Which of the following statements is true of the nucleus of an atom? 1) the nucleus occupies only a tiny fraction of the total volume of the atom, and most of the mass of the atom is concentrated in the region surrounding the nucleus 2) the nucleus occupies a large fraction of the total volume of the atom, and most of the mass of the atom is concentrated in the region surrounding the nucleus 3) the nucleus occupies a large fraction of the total volume of the atom, and most of the mass of the atom is concentrated in its nucleus 4) the nucleus occupies only a tiny fraction of the total volume of the atom, and most of the mass of the atom is concentrated in its nucleus

the nucleus occupies only a tiny fraction of the total volume of the atom, and most of the mass of the atom is concentrated in its nucleus

Which of the following defines the atomic number of an atom? 1) number of neutrons in the atom 2) the total number of protons, neutrons, and electrons in the atom 3) the number of protons in the atom 4) the total number of protons and neutrons in the atom

the number of protons in the atom

What defines the mass number of an atom?

the total number of protons and neutrons in the atom

Sodium is a highly reactive metal and chlorine is a toxic gas. When they are mixed, they form sodium chloride, which is essential for life. Which of the following statements is true when sodium and chlorine are brought into contact with one another? 1) they may form a heterogeneous or a homogeneous mixture depending on the conditions that prevail during the interaction 2) they form a heterogeneous mixture 3) they form a compound 4) they form a homogeneous mixture

they form a compound

Which of the following statements best characterizes the isotopes of an element? 1) they have different numbers of neutrons 2) they have different numbers of protons 3) they have different numbers of electrons 4) they have different numbers of protons, neutrons, and electrons

they have different numbers of neutrons