Identify X in the Expression X

Q3: Which is expected to be the most

Q4: Which of the following pairs are isotopes?<br>A)

Q5: How is the term "atomic number" defined

Q6: Ionization energy _ from top to bottom

Q7: Fr+ is called _.<br>A) a cation<br>B) an

Q9: The breakthrough Dmitri Mendeleev had when constructing

Q10: What is the atomic number of uranium-235?<br>A)

Q11: What name is commonly given to the

Q12: Barium is an alkali earth metal.

Q13: An alpha particle consists of two protons