Name:_______________________
Period:______
Chemistry Test Review Unit 2
1 ) How many protons, electron and neutrons does gold-197 have?
2) How many protons, electron and neutrons does bromine-81 have?
3) How many protons, electron and neutrons does chromium-54 have?
4) What was Dalton’s model of the atom?
5) What was Thomson’s model of the atom?
6) What was Rutherford’s model of the atom?
7) What was Bohr’s model of the atom?
8) What was the chronological order of the four scientist we discussed?
9) If 69.15% of the isotopes of an element have a mass of 63 and 30.85% of the isotopes have a mass of
65, what is the average atomic mass of the element?
10) If 75.76% of the isotopes of an element have a mass of 35 and 24.24% of the isotopes have a mass of
37, what is the average atomic mass of the element?
11) What characteristic of an atom decides which element it is?
12) What was Thomson’s experiment? What were Thomson’s observations during this experiment and
what did he conclude/discover based on those observations?
13) What was Rutherford’s experiment? What were Rutherford’s observations during this experiment
and what did he conclude/discover based on those observations?
14) Which subatomic particles are in the nucleus and which are outside the nucleus?
15) What is true about the number of protons and electrons in a neutral atom?
59
16) How many neutrons, protons, and electrons are in 27
𝐶𝑜?
17) How many neutrons, protons, and electrons are in 39
19𝐾 ?
18) A sample of element X contains 50.69% 79X atoms and 49.31% 81X atoms. What is the average
isotopic mass?
19) A sample of element X contains 78.99% 24X atoms, 10% 25X and 11.01% 26X atoms. What is the
average isotopic mass?
20) What is an isotope?
21) What is the mass number and atomic number of Magnesium that has 12 protons, 12 electrons and
12 neutrons?
22) What is the mass number and atomic number of krypton that has 36 protons, 36 electrons and 48
neutrons?
23) What happens when an electron’s energy is increased? Decreased?
24) How do the mass of a proton, electron and neutron compare to one another?
25) This is a picture of an atom:
What is the atomic number? What is the mass number? What element is it?
26) What is the charge of the nucleus of an aluminum atom?
27) What is the charge of the nucleus of a titanium atom?