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  1. Problems
  2. /The Periodic Table
  3. /Development of the Periodic Table

Development of the Periodic Table

Chemistry
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More in The Periodic TableDevelopment of the Periodic TablePeriodic TrendsGroups and Families
21 problems
Type:
1.
An element of period 4 has the outer configuration 3d⁵ 4s². New
High School (11–12) · Development of the Periodic Table, Groups and FamiliesStemPy LabStemPy Lab
Medium
2.
A lanthanoid has the configuration [Xe] 4f⁷ 6s². New
High School (11–12) · Development of the Periodic Table, Groups and FamiliesStemPy LabStemPy Lab
Hard
3.
An element sits in period 5 and group 14. Write its outer configuration and find its atomic number. New
High School (11–12) · Development of the Periodic Table, Groups and FamiliesStemPy LabStemPy Lab
Medium
4.
Arsenic has Z = 33. Write its configuration with a noble gas core, and find its period, group and… New
High School (11–12) · Development of the Periodic Table, Groups and FamiliesStemPy LabStemPy Lab
Easy
5.
Period 6 begins with the filling of the 6s subshell. New
High School (11–12) · Development of the Periodic TableStemPy LabStemPy Lab
Medium
6.
Give the temporary IUPAC name and symbol of the elements with Z = 106, 109 and 120. New
High School (11–12) · Development of the Periodic TableStemPy LabStemPy Lab
Easy
7.
Three metals give these values of √(ν) for their strongest X-ray line: calcium (Z = 20), 9.46 ×… New
High School (11–12) · Development of the Periodic TableStemPy LabStemPy Lab
Medium
8.
Tellurium (127.6 u) is heavier than iodine (126.9 u). New
High School (11–12) · Development of the Periodic TableStemPy LabStemPy Lab
Hard
9.
Newlands' list, in order of atomic mass, began: H, Li, Be, B, C, N, O, F, Na, Mg, Al, Si, P, S, Cl… New
High School (11–12) · Development of the Periodic TableStemPy LabStemPy Lab
Medium
10.
In Mendeleev's table the gap for eka-silicon had silicon (28.09 u) above, tin (118.71 u) below… New
High School (11–12) · Development of the Periodic TableStemPy LabStemPy Lab
Medium
11.
Calcium (40.08 u), strontium (87.62 u) and barium (137.33 u) behave alike. New
High School (11–12) · Development of the Periodic TableStemPy LabStemPy Lab
Easy
12.
The periods of the modern table hold 2, 8, 8, 18, 18, 32 and 32 elements.
High School (9–10), General · Development of the Periodic TableStemPy LabStemPy Lab
Medium
13.
An element is in period 3 and group 16. Find its electron arrangement, its atomic number and its…
High School (9–10), General · Development of the Periodic TableStemPy LabStemPy Lab
Medium
14.
Six elements have these electron arrangements.
High School (9–10), General · Development of the Periodic TableStemPy LabStemPy Lab
Medium
15.
Find the electron arrangement, the period and the group of the element with the atomic number 15.
High School (9–10), General · Development of the Periodic TableStemPy LabStemPy Lab
Easy
16.
Argon has an atomic mass of 39.9 u and potassium 39.1 u.
High School (9–10), General · Development of the Periodic TableStemPy LabStemPy Lab
Medium
17.
Mendeleev left gaps in his table. Why was that important?
High School (9–10), General · Development of the Periodic TableStemPy LabStemPy Lab
Easy
18.
Mendeleev also predicted the oxide of eka-silicon.
High School (9–10), General · Development of the Periodic TableStemPy LabStemPy Lab
Medium
19.
The atomic masses of beryllium, magnesium and calcium are 9.0 u, 24.3 u and 40.1 u.
High School (9–10), General · Development of the Periodic TableStemPy LabStemPy Lab
Medium
20.
Give two reasons why Newlands' law of octaves was not accepted for all of the elements.
High School (9–10), General · Development of the Periodic TableStemPy LabStemPy Lab
Easy
21.
The atomic masses of potassium and caesium are 39.1 u and 132.9 u.
High School (9–10), General · Development of the Periodic TableStemPy LabStemPy Lab
Easy