Download Review Questions: Name Period 1. The atom (smallest unit of an

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_______________charge.
____________,_________________
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_______combination
______________?
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Review Questions:
Name
Period
1.
The atom (smallest unit of an element) is composed of 3 fundamental particles
and
2.
An atom of He on a distant star has (the same, a different)
of electrons and protons at
an atom of He on Earth.
3.
Each element has a unique number of protons and electrons in its atoms. Would it be possible to identify an
element if you know the number of protons and electrons in its atoms? Why?
4.
Unless otherwise stated, it is assumed that a given atom is neutral. Protons are positively charged and electrons are
negatively charged. If a boron atom contains 5 protons, how many electrons will it have_______________________
5.
An atom has eight electrons, how many protons will it have?_________________
6.
Using a periodic table, how many protons do the following atoms have Sodium, Gold, Oxygen, and
,
Silicon?
7.
The number of protons in an atom is called the atomic number. What is the atomic number of the following atoms
He,
Co,
Pr,
and
N?_____
,_____
8.
The element zinc (Zn> has an atomic number of 30. How many protons does it have?_______________
9.
How many electrons does an atom of zinc have?______________
10. How many electrons do the following atoms have carbon, lithium, sulfur, and
chlorine?
,
Bohr Mod&
11. What is the atomic number of the element represented?________________________
12. What is the atom represented in the Bohr model?______________________
13. An electron always carries a negative charge. A proton carries the exact opposite charge. A proton has a (positive,
negative, neutral)
14. It takes about 1836 electrons to equal the mass of one proton. Hydrogen atoms have one proton and one electron.
The greatest portion of mass comes from hydrogen’s (proton, electron)___________________
15. The element helium represented in the Bohr model above has what atomic number?____________
16. A neutral atom of oxygen has how many protons
? electrons
?
17. The mass of an atom is primarily derived from the proton and neutron. Since the proton has a positive charge which
equals out the negative charge of the electron, the charge on the neutron must be___________________________
18. In the Bohr model for helium pictured above, the 2 white circles represent electrons. Which particles are in the
center of this atomic model
,
19. If the charge on an electron is represented by -1, then the charge on a proton is
neutron is
?
The charge on a
______________protons
________
_________________neutrons.
______will
20. Neutrons can be found in all of the neutral atoms of the elements except
21. The number 16 represent in the box above represents the__________________________________
number of these subatomic particles.
,
22. The nucleus of an atom is made up of what two particles
,
,
it is also the
—.
These two particles
make up nearly 99,9% of an atom’s mass.
23. Adding the number of neutrons and
give you the atomic mass number for an element.
24. The atom Ar has 18 protons and an atomic mass number of 40. How many neutrons does it have?______________
r24
Cr
52
25. Chromium (Cr) has
and
26. The letter “A” represents an unknown element. Use a periodic table to identify the element.
27. Fill in the following information for hydrogen.
The atomic number is
The atomic mass number is
The number of protons
The number of neutrons