The purpose of this lab is to identify periodic trends in the activity of the main group
II. Data Tables
Comparison of Reactions Among Metals
Reaction with Water
Observatio ns (Compare the Rate of the Reactions) pH
Reaction with Acid
Observatio ns (Compare the Rate of the Reactions)
1. Determination of Percent Error % error =
Value(accepted) – Value(experimental) X 100 Value(accepted) % error =
5.91 g/cm^3 – 5.70 g/cm^3 X 100 5.91 g/cm^3 % error = 3.55% V. Questions 1. Which Group 1 metal, lithium, sodium, or potassium, is most active? Cite your evidence.
Potassium is most active, it reacted faster when placed in water and also, it is farthest down the periodic table, so it has the largest atomic radius.
2. Which Group 2 metal, magnesium or calcium, is more active? Cite your evidence.
Magnesium and Calcium are both in Group 2, meaning they have two valence electrons each, making them both very reactive, however, Calcium in more reactive of the two because it is farther down the group. Also, by comparison with the experiment, it shows that Calcium released gas faster and bubbles faster. 3. Write a general statement that describes the periodic trend in metal activity down a group (vertical column) of the periodic table. Is this consistent with the trend of ionization energy? Why or why not?
Electronegativity increases as you go up the group; ionization energy also increases are you go up a group. 4. Which Period 3 metal, sodium or magnesium, is more active? Which Period 4 metal, potassium or calcium, is more active? Cite your evidence.
Sodium and potassium are more reactive because they are closer to the left bottom of the periodic table than calcium and magnesium.
5. Write a general statement that describes the periodic trend in metal activity across a period
(horizontal row) of the