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  1. Problems
  2. /The Periodic Table
  3. /Periodic Trends

Periodic Trends

Chemistry
+ Upload a Problem
More in The Periodic TableDevelopment of the Periodic TablePeriodic TrendsGroups and Families
21 problems
Type:
1.
On the Pauling scale sodium is 0.9, hydrogen 2.1, carbon 2.5 and chlorine 3.0. New
High School (11–12) · Periodic Trends, Groups and FamiliesStemPy LabStemPy Lab
Hard
2.
Sodium oxide, aluminium oxide and sulphur trioxide are each tested with water, with dilute acid and… New
High School (11–12) · Periodic Trends, Groups and FamiliesStemPy LabStemPy Lab
Medium
3.
Use the valences of the groups to write three formulas. New
High School (11–12) · Periodic Trends, Groups and FamiliesStemPy LabStemPy Lab
Easy
4.
The electron gain enthalpy of chlorine is -349 kJ mol⁻¹ and that of fluorine -328 kJ mol⁻¹. New
High School (11–12) · Periodic TrendsStemPy LabStemPy Lab
Hard
5.
The first ionisation enthalpy of nitrogen is 1402 kJ mol⁻¹ and that of oxygen is 1314 kJ mol⁻¹… New
High School (11–12) · Periodic TrendsStemPy LabStemPy Lab
Medium
6.
The first four ionisation enthalpies of an element are 578, 1817, 2745 and 11577 kJ mol⁻¹. New
High School (11–12) · Periodic TrendsStemPy LabStemPy Lab
Medium
7.
A sodium street lamp holds sodium vapour. New
High School (11–12) · Periodic TrendsStemPy LabStemPy Lab
Easy
8.
Suppose only the two 1s electrons shield the outer electrons of period 2, so S = 2. New
High School (11–12) · Periodic TrendsStemPy LabStemPy Lab
Hard
9.
The atomic radius of sodium is 186 pm. Potassium, below it in group 1, is 231 pm. New
High School (11–12) · Periodic TrendsStemPy LabStemPy Lab
Medium
10.
The ions S²⁻, Cl⁻, K⁺ and Ca²⁺ all have the same number of electrons. New
High School (11–12) · Periodic TrendsStemPy LabStemPy Lab
Medium
11.
The two nuclei in a bromine molecule, Br₂, are 228 pm apart. New
High School (11–12) · Periodic TrendsStemPy LabStemPy Lab
Easy
12.
The valency of oxygen is 2. Find the formula of the oxide of (a) sodium, (b) magnesium, (c)…
High School (9–10), General · Periodic TrendsStemPy LabStemPy Lab
Medium
13.
Which is more reactive, and why? (a) Ca or Mg, as metals. (b) Rb or K. (c) Cl or Br, as non-metals.
High School (9–10), General · Periodic TrendsStemPy LabStemPy Lab
Medium
14.
Say whether each oxide is acidic, basic or amphoteric: K₂O, CaO, CO₂, Al₂O₃ and SO₂.
High School (9–10), General · Periodic TrendsStemPy LabStemPy Lab
Medium
15.
Four elements have these electron arrangements: 2, 3; 2, 8, 6; 2, 1; and 2, 8, 4.
High School (9–10), General · Periodic TrendsStemPy LabStemPy Lab
Medium
16.
Arrange beryllium, magnesium, calcium and strontium (a) in increasing order of atomic size, and (b)…
High School (9–10), General · Periodic TrendsStemPy LabStemPy Lab
Medium
17.
Which atom is bigger? Give a reason for each. (a) Be or Ba. (b) Mg or Cl. (c) B or F. (d) Rb or Li.
High School (9–10), General · Periodic TrendsStemPy LabStemPy Lab
Medium
18.
The atomic radius of magnesium is 160 pm and of sulphur 103 pm.
High School (9–10), General · Periodic TrendsStemPy LabStemPy Lab
Easy
19.
Find the valency of the elements with these atomic numbers: 6, 9, 11, 13 and 15.
High School (9–10), General · Periodic Trends, Electronic Configuration and ValencyStemPy LabStemPy Lab
Medium
20.
Why do lithium, sodium and potassium all have a valency of 1?
High School (9–10), General · Periodic Trends, Electronic Configuration and ValencyStemPy LabStemPy Lab
Easy
21.
Selenium is in group 16, below sulphur. Its arrangement is 2, 8, 18, 6.
High School (9–10), General · Periodic Trends, Electronic Configuration and ValencyStemPy LabStemPy Lab
Easy