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Problems

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387 problems
Type:
1.
Count the valence electrons in the sulfate ion, SO₄²⁻. New
High School (11–12) · Chemical BondingStemPy LabStemPy Lab
Medium
2.
Nitrous oxide, N₂O, has the atoms in the order N-N-O. New
High School (11–12) · Chemical BondingStemPy LabStemPy Lab
Hard
3.
For each molecule, count the electrons around the central atom, and say whether it has an… New
High School (11–12) · Chemical BondingStemPy LabStemPy Lab
Medium
4.
Find the number of valence electrons in the Lewis structures of the chlorate ion, ClO₃⁻, the… New
High School (11–12) · Chemical BondingStemPy LabStemPy Lab
Easy
5.
For potassium chloride, in kJ/mol: sublimation of potassium +89, half the bond enthalpy of chlorine… New
High School (11–12) · Chemical BondingStemPy LabStemPy Lab
Medium
6.
Forming Mg²⁺ and O²⁻ seems costly. In kJ/mol: sublimation of magnesium +148; half the bond enthalpy… New
High School (11–12) · Chemical BondingStemPy LabStemPy Lab
Hard
7.
Arrange MgO, CaO, NaF and KBr in order of decreasing lattice enthalpy. Give a reason for each step. New
High School (11–12) · Chemical BondingStemPy LabStemPy Lab
Medium
8.
For lithium fluoride, in kJ/mol: sublimation of lithium +159, half the bond enthalpy of fluorine… New
High School (11–12) · Chemical BondingStemPy LabStemPy Lab
Easy
9.
Carbon to carbon bonds have these lengths and bond enthalpies: single, 154 pm and 348 kJ/mol… New
High School (11–12) · Chemical BondingStemPy LabStemPy Lab
Medium
10.
The carbonate ion, CO₃²⁻, has three canonical forms. New
High School (11–12) · Chemical BondingStemPy LabStemPy Lab
Medium
11.
Chlorine monofluoride, ClF, has a dipole moment of 0.88 D and a bond length of 163 pm. New
High School (11–12) · Chemical BondingStemPy LabStemPy Lab
Medium
12.
Silicon (4 outer electrons), phosphorus (5) and sulphur (6) each form a chloride: SiCl₄, PCl₃ and… New
High School (11–12) · Chemical BondingStemPy LabStemPy Lab
Easy
13.
Xenon is a noble gas with 8 outer electrons, yet it forms XeF₂, XeF₄ and XeF₆. New
High School (11–12) · Chemical BondingStemPy LabStemPy Lab
Medium
14.
Predict the shapes of the ammonium ion NH₄⁺, the hydronium ion H₃O⁺ and the amide ion NH₂⁻. New
High School (11–12) · Chemical BondingStemPy LabStemPy Lab
Medium
15.
Chlorine has 7 outer electrons. Find the electron pairs and lone pairs on chlorine in ClF₃. New
High School (11–12) · Chemical BondingStemPy LabStemPy Lab
Hard
16.
The bond enthalpy of hydrogen is 435.8 kJ mol⁻¹. New
High School (11–12) · Chemical BondingStemPy LabStemPy Lab
Easy
17.
Count the sigma and pi bonds in propene, CH₂=CH-CH₃, and in propyne, HC≡C-CH₃. New
High School (11–12) · Chemical BondingStemPy LabStemPy Lab
Medium
18.
Hydrogen chloride, chlorine and nitrogen are all covalent. New
High School (11–12) · Chemical BondingStemPy LabStemPy Lab
Medium
19.
In ethane, ethene and ethyne, the carbon atoms are sp³, sp² and sp. New
High School (11–12) · Chemical BondingStemPy LabStemPy Lab
Medium
20.
Ethene, CH₂=CH₂, is flat. What is the hybridisation of each carbon atom? New
High School (11–12) · Chemical BondingStemPy LabStemPy Lab
Medium
21.
Phosphorus is 3s² 3p³. Explain how it forms five bonds in PCl₅ and name the hybridisation. New
High School (11–12) · Chemical BondingStemPy LabStemPy Lab
Hard
22.
Two atoms of the second period come together, and each brings its 1s, 2s and three 2p orbitals. New
High School (11–12) · Chemical BondingStemPy LabStemPy Lab
Easy
23.
The C₂ molecule, found in flames and in comets, has 12 electrons. New
High School (11–12) · Chemical BondingStemPy LabStemPy Lab
Medium
24.
Two helium atoms have four electrons between them. New
High School (11–12) · Chemical BondingStemPy LabStemPy Lab
Easy
25.
Nitrogen, N₂, has 10 bonding and 4 antibonding electrons. New
High School (11–12) · Chemical BondingStemPy LabStemPy Lab
Medium
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Showing 1–25 of 387