Question

test periodic table and trends
put the letter of the answer in the blank.

1. which elements are metalloids?

• krypton, neon, radon
• chromium, cobalt, zinc
• arsenic, antimony, silicon
• sodium, potassium, rubidium

1. which of the following elements is a non - metal?

• magnesium
• boron
• carbon
• calcium

1. which of the following elements is a metal?

• p
• n
• k
• si

1. how did mendeleev arrange the first periodic table?

• in order of increasing density
• in order of increasing atomic number
• in alphabetical order
• in order of increasing atomic mass

1. what two elements have properties most similar to sodium (na)?

• lithium and potassium
• selenium and scandium
• magnesium and aluminum
• krypton and xenon

1. examine the periodic table below and determine the correct answer.

• i. element d is a halogen
• ii. element f is a good conductor
• iii. elements c and d share similar properties
• iv. element g has 3 valence electrons
• v. elements a and c are alkali metals
• a. i, ii, iii and iv are true
• b. i, iv and v are true
• c. i, iii are iv true
• d. i, iii are iv true

1. which of these elements has the larger atomic radii and why? li vs rb

• a. rb is the largest because it has the most principal energy levels or shells.
• b. li is the largest because it has the least amount of shielding effect.
• c. rb is the largest because it has the least amount of shielding effect.
• d. li is the largest because it has the most principal energy levels or shells.

1. element a and b are in the same period. element a has 2 valence electrons and element b has 5 valence electrons. which would have a smaller radius (size)?

• a. element a because it has fewer valence electrons.
• b. element b because it has a greater shielding effect.
• c. element a because it has a greater shielding effect.
• d. element b because more electrons create a stronger pull towards the nucleus.

1. in general, how does ionization energy change within groups and across periods?

• a. it increases from top to bottom within a group, and increases from left to right across a period.
• b. it increases from top to bottom within a group, and remains about constant throughout a period.
• c. it increases from bottom to top within a group, and increases from left to right across a period.
• d. it increases from top to bottom within a group, and decreases from left to right across a period.

1. compare the bohr models for d and e only. which would have a higher ionization energy?

• a. e because it is easier to remove its valence electron.
• b. d because it is easier to remove its valence electron.
• c. d because it is harder to remove its valence electron.
• d. e because it is harder to remove its valence electron.

*note these models are not drawn to scale

Explanation:

1. Metalloids include silicon, germanium, arsenic, antimony, etc. So the answer for question 1 is the option with arsenic, antimony, silicon.
2. Non - metals like carbon are known. Magnesium is a metal, boron has some metallic and non - metallic properties but carbon is a typical non - metal for question 2.
3. Potassium (K) is a metal. Phosphorus (P) and nitrogen (N) are non - metals, and Si is a metalloid for question 3.
4. Mendeleev arranged the first periodic table in order of increasing atomic mass for question 4.
5. Elements in the same group have similar properties. Sodium is in Group 1, and lithium and potassium are also in Group 1 for question 5.
6. Analyzing the periodic table characteristics: Halogens are in Group 17, alkali metals in Group 1. Based on the positions of elements in the table for question 6.
7. Atomic radius increases down a group. Rubidium (Rb) is below lithium (Li) in the alkali metal group, so Rb has more principal energy levels and a larger atomic radius for question 7.
8. In the same period, as the number of valence electrons increases, the nuclear charge attracts the electrons more strongly, reducing the atomic radius. Element B with more valence electrons has a smaller radius for question 8.
9. Ionization energy increases from bottom to top within a group and from left to right across a period due to changes in nuclear charge and electron shielding for question 9.
10. Ionization energy is the energy required to remove a valence electron. A smaller atom with a more strongly held valence electron has a higher ionization energy. Analyzing the Bohr models of D and E for question 10.

Answer:

1. C. Arsenic, antimony, silicon
2. C. Carbon
3. C. K
4. D. In order of increasing atomic mass
5. A. Lithium and potassium
6. B. I, IV and V are true
7. A. Rb is the largest because it has the most principal energy levels or shells.
8. D. Element B because more electrons create a stronger pull towards the nucleus.
9. C. It increases from bottom to top within a group, and increases from left to right across a period.
10. C. D because it is harder to remove its valence electron.