Name: 
 

Ch 4 - Atomic Structure Test



Numeric Response (Value 5)
 

 1. 

Use the periodic table to determine the number of neutrons in nitrogen-14.

 

 2. 

What is the relative charge of a proton?

 

 3. 

Use the periodic table to determine the number of electrons in a neutral atom of lithium.

 

 4. 

Calculate the number of neutrons in nr004-1.jpgPb.

 

 5. 

What is the atomic number for an element with 41 neutrons and a mass number of 80?

 

Matching (Value 10)
 
 
Match each item with the correct statement below.
a.
proton
d.
electron
b.
nucleus
e.
neutron
c.
atom
 

 6. 

the central part of an atom, containing protons and neutrons
 

 7. 

a positively charged subatomic particle
 

 8. 

a subatomic particle with no charge
 

 9. 

the smallest particle of an element that retains the properties of that element
 

 10. 

a negatively charged subatomic particle
 
 
Match each item with the correct statement below.
a.
mass number
d.
atomic mass
b.
atomic mass unit
e.
isotope
c.
atomic number
 

 11. 

the weighted average of the masses of the isotopes of an element
 

 12. 

the number of protons in the nucleus of an element
 

 13. 

atoms with the same number of protons, but different numbers of neutrons in the nucleus of an atom
 

 14. 

one-twelfth the mass of a carbon atom having six protons and six neutrons
 

 15. 

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

Multiple Choice (Value 25)
Identify the choice that best completes the statement or answers the question.
 

 16. 

The comparison of the number of atoms in a copper coin the size of a penny with the number of people on Earth is made to illustrate which of the following?
a.
that atoms are indivisible
b.
that atoms are very small
c.
that atoms are very large
d.
that in a copper penny, there is one atom for every person on Earth
 

 17. 

The atomic number of an element is the total number of which particles in the nucleus?
a.
neutrons
c.
electrons
b.
protons
d.
protons and electrons
 

 18. 

All atoms are ____.
a.
positively charged, with the number of protons exceeding the number of electrons
b.
negatively charged, with the number of electrons exceeding the number of protons
c.
neutral, with the number of protons equaling the number of electrons
d.
neutral, with the number of protons equaling the number of electrons, which is equal to the number of neutrons
 

 19. 

If E is the symbol for an element, which two of the following symbols represent isotopes of the same element?
1. mc019-1.jpgE2. mc019-2.jpgE3. mc019-3.jpgE4. mc019-4.jpgE
a.
1 and 2
c.
1 and 4
b.
3 and 4
d.
2 and 3
 

 20. 

Which of the following is necessary to calculate the atomic mass of an element?
a.
the atomic mass of carbon-12
b.
the atomic number of the element
c.
the relative masses of the element’s protons and neutrons
d.
the masses of each isotope of the element
 

 21. 

Select the correct symbol for an atom of tritium.
a.
mc021-1.jpgn
c.
mc021-3.jpgH
b.
mc021-2.jpgH
d.
mc021-4.jpgH
 

 22. 

How is the number of neutrons in the nucleus of an atom calculated?
a.
Add the number of electrons and protons together.
b.
Subtract the number of electrons from the number of protons.
c.
Subtract the number of protons from the mass number.
d.
Add the mass number to the number of electrons.
 

 23. 

Which hypothesis led to the discovery of the proton?
a.
When a neutral hydrogen atom loses an electron, a positively-charged particle should remain.
b.
A proton should be 1840 times heavier than an electron.
c.
Cathode rays should be attracted to a positively-charged plate.
d.
The nucleus of an atom should contain neutrons.
 

 24. 

Which of the following is correct concerning subatomic particles?
a.
The electron was discovered by Goldstein in 1886.
b.
The neutron was discovered by Chadwick in 1932.
c.
The proton was discovered by Thomson in 1880.
d.
Cathode rays were found to be made of protons.
 

 25. 

Which of the following was NOT among Democritus’s ideas?
a.
Matter consists of tiny particles called atoms.
b.
Atoms are indivisible.
c.
Atoms retain their identity in a chemical reaction.
d.
Atoms are indestructible.
 

 26. 

Why do chemists use relative masses of atoms compared to a reference isotope rather than the actual masses of the atoms?
a.
The actual mass of an electron is very large compared to the actual mass of a proton.
b.
The actual masses of atoms are very small and difficult to work with.
c.
The number of subatomic particles in atoms of different elements varies.
d.
The actual masses of protons, electrons, and neutrons are not known.
 

 27. 

What does the number 84 in the name krypton-84 represent?
a.
the atomic number
c.
the sum of the protons and electrons
b.
the mass number
d.
twice the number of protons
 

 28. 

Using the periodic table, determine the number of neutrons in mc028-1.jpgO.
a.
4
c.
16
b.
8
d.
24
 

 29. 

Which of the following statements is NOT true?
a.
Atoms of the same element can have different masses.
b.
Atoms of isotopes of an element have different numbers of protons.
c.
The nucleus of an atom has a positive charge.
d.
Atoms are mostly empty space.
 

 30. 

Dalton hypothesized that atoms are indivisible and that all atoms of an element are identical. It is now known that ____.
a.
all of Dalton's hypotheses are correct
b.
atoms of an element can have different numbers of protons
c.
atoms are divisible
d.
all atoms of an element are not identical but they must all have the same mass
 

 31. 

Which of the following is NOT a part of Dalton's atomic theory?
a.
All elements are composed of atoms.
b.
Atoms are always in motion.
c.
Atoms of the same element are identical.
d.
Atoms that combine do so in simple whole-number ratios.
 

 32. 

Who was the man who lived from 460B.C.–370B.C. and was among the first to suggest the idea of atoms?
a.
Atomos
c.
Democritus
b.
Dalton
d.
Thomson
 

 33. 

The atomic mass of an element depends upon the ____.
a.
mass of each electron in that element
b.
mass of each isotope of that element
c.
relative abundance of protons in that element
d.
mass and relative abundance of each isotope of that element
 

 34. 

Which of the following equals one atomic mass unit?
a.
the mass of one electron
b.
the mass of one helium-4 atom
c.
the mass of one carbon-12 atom
d.
one-twelfth the mass of one carbon-12 atom
 

 35. 

In which of the following sets is the symbol of the element, the number of protons, and the number of electrons given correctly?
a.
In, 49 protons, 49 electrons
c.
Cs, 55 protons, 132.9 electrons
b.
Zn, 30 protons, 60 electrons
d.
F, 19 protons, 19 electrons
 

 36. 

Why did J. J. Thomson reason that electrons must be a part of the atoms of all elements?
a.
Cathode rays are negatively-charged particles.
b.
Cathode rays can be deflected by magnets.
c.
An electron is 2000 times lighter than a hydrogen atom.
d.
Charge-to-mass ratio of electrons was the same, regardless of the gas used.
 

 37. 

Dalton's atomic theory included which idea?
a.
All atoms of all elements are the same size.
b.
Atoms of different elements always combine in one-to-one ratios.
c.
Atoms of the same element are always identical.
d.
Individual atoms can be seen with a microscope.
 

 38. 

What is the relative mass of an electron?
a.
1/1840 the mass of a hydrogen atom
c.
1/1840 the mass of a C-12 atom
b.
1/1840 the mass of a neutron + proton
d.
1/1840 the mass of an alpha particle
 

 39. 

How many protons, electrons, and neutrons does an atom with atomic number 50 and mass number 125 contain?
a.
50 protons, 50 electrons, 75 neutrons
c.
120 neutrons, 50 protons, 75 electrons
b.
75 electrons, 50 protons, 50 neutrons
d.
70 neutrons, 75 protons, 50 electrons
 

 40. 

The range in size of most atomic radii is approximately ____.
a.
2 to 5 cm
c.
5 mc040-1.jpg 10mc040-2.jpg m to 2 mc040-3.jpg 10mc040-4.jpg m
b.
2 to 5 nm
d.
5 mc040-5.jpg 10mc040-6.jpg m to 2 mc040-7.jpg 10mc040-8.jpg m
 



 
Check Your Work     Start Over