Grade
Which of the following is the best description of an alpha particle?
- correct answer A helium nucleus.
An ancient human skull was found in the foothills of Rexburg. In an attempt to determine when the
person had lived the skull was carbon dated. It was determined that the skull contained 80% of the 14C
that is normally found in living tissue. Approximately how old is the skull. The T1/2 for 14C is 5730 years.
- correct answer 1845 years
Lead-210 (Z=82) decays by alpha emission. What is the mass number of the resulting atom.
- correct answer 206
Carbon-14 ( 146C) is a radioactive element that emits beta particles as it decays. What does Carbon-14
decay to?
- correct answer Nitrogen-14
Which of the following is not one of the elements making up 96% of living matter?
- correct answer Na
Sodium has an atomic number of 11, How many electrons does sodium have in its 3rd shell?
- correct answer 1
Which of the following elements has a valence of two
- correct answer Nitrogen, Carbon, Hydrogen
Which of the following is the best definition of an electron orbital?
- correct answer A three dimensional space where electrons reside