PS Midterm Review

The graph shows the heating of an unknown substance. (It is not water!) Its melting point is ______.

• between 35 degrees C and 70 degrees C

• 70 degrees C

• 100 degrees C

• 0 degrees C

The diagrams show a sulfur ion and a chlorine ion. What is the main difference between these two ions?

• The number of atomic orbitals is different.

• The number of neutrons is different.

• The number of protons is different.

• The number of electrons is different.

An isotope of an unknown element has 17 neutrons and a mass number of 32. What is the symbol of this isotope?

Fluorine is an element that forms Fluoride. Fluoride is added to toothpaste to aid in protecting teeth. An atom of fluorine has the atomic number 9, and its mass number is 19 amu. Which of the following shows a neutral atom of fluorine?

• W

• X

• Y

• Z

Nuclear reactors use the transmutation of Uranium to produce the heat/steam that drives the turbines. Which type of reaction is this?

• Angry

• Fission

• Synthesis

• Fusion

What is the process shown in the diagram?

• Futile

• Fission

• Decomposition

• Fusion

Which process produces the energy in the Sun?

• Fusion

• Fission

The half-life of a radioactive isotope is the time required for one-half of the initial mass to decay into a different element. The radioactive decay of iodine is shown in the graph. What is the half-life of radioactive iodine?

• 8 days

• 16 days

• 32 days

• 48 days

A 100-gram sample of radium-226 has a half life of 1600 years. How long will it take before there are only 12.5 grams of the radioactive radium-226 remaining?

• 1600 years

• 3200 years

• 4800 years

• 6400 years

Nuclear equation below represents the beta decay of Lanthanum-144. What element will be represented by the blank?

• Cerium-58

• Barium-56

• Praseodymium-59

• Neodymium-60