Unit 3 ExamFamous scientists

Periodic table arrangementPeriodic Trends

Atomic structureCalculations: light and atomic mass

1. Which scientist is credited with discovering the nucleus?

2. The existence of _________ disproved Dalton’s theory that all atoms of an element were identical.

3. Which scientist studied experiments with light to describe the orbits (or energy levels) where electrons exist?

4. Which scientist proved the existence of negatively charged subatomic particles?

5. What element is in group 16 of period 4?

6. What halogen is located in period 2?

7. What element has 5 valence electrons in the 2nd energy level?

8. A group on the periodic table contains the most reactive metals. How many valence electrons do these elements have?

9. Which of the following elements would have properties similar to calcium and why?

aluminum potassium

sulfur strontium

Set up your paper like this

# protons # neutrons # electrons

For the following atoms or ions, give the numbers of protons, neutrons, and

electrons.

10. a neutral atom of helium with a mass number of 4

11. sodium-23

12. a rubidium-85 ion with a +1 charge

12. aluminum-27

13. carbon-14

14. a -3 anion of nitrogen-14

15. 9Be2+

4

Periodic Trends

Find these elements on the periodic and compare their location to answer

the questions.

16. Which of the following elements would have the largest atomic radius?

Li Na Rb Cs

17. Which of the following elements would have the smallest atomic radius?

Mg Si Al Cl

18. Which of the following elements would have the lowest ionization energy?

Li Be B O

19. Which of the following elements would have the highest ionization energy?

I Cl F Br

20. ___________ is the tendency of an element to attract shared electrons.

21. Which of the following elements has the lowest electronegativity?

Cs K Li Na

22. Which of these elements would make a bond with nitrogen? (similar to P bonding with B)

Al Mg Ba C

23. Which of these elements would make a bond with chlorine? (similar to K bonding with Br)

O F Li Xe

Get a calculator so we can practice some of the math

problems that will be on the test

24. What is the frequency of light with a wavelength of 5.60 x 10-7 m?

25. Calculate the energy of a photon with a frequency of 7.35 E 8 Hz

26. The % abundance and atomic mass of isotopes of element Z are given in the table. Calculate the average atomic mass of the element.

Isotope % abundance Atomic mass (amu)

35Z 75.53% 34.96937Z 24.47% 36.966