Module 1: Properties and Structure of Matter
The number of protons in an atom defines this.
What is the atomic number?
6.022 x 1023
What is Avogadro's Number?
This type of reaction involves a single substance breaking down into two or more simpler substances.
What is a decomposition reaction?
This element’s symbol is the same as the first two letters of the word No.
What is Nobelium (No)?
The law that allows enthalpy changes to be calculated indirectly through a series of steps.
What is Hess' Law?
Write the electron configuration of magnesium (Mg, Z = 12).
What is 1s² 2s² 2p⁶ 3s²?
The substance that is totally consumed when the chemical reaction is complete, while other reactant remains
What is the limiting reagent?
This type of reaction decreases enthalpy and releases energy to the surroundings
What is an exothermic reaction?
This gas makes up about 78% of Earth’s atmosphere.
What is nitrogen (N₂)?
Explain why an exothermic reaction can be non-spontaneous.
If entropy decreases and TΔS > ΔH, then ΔG is positive.
Heterogenous Mixture
What is a mixture of two substances that stay physically separate?
Shorthand diagrams for showing how electrons are shared in a covalent bond
What are Lewis Dot diagrams?
Balance this equation:
Al + O₂ → Al₂O₃
4Al + 3O₂ → 2Al₂O₃
Discovered in 1898, this radioactive element’s symbol is Ra and it was famously studied by Marie Curie.
What is radium?
Calculate q when 50.0 g of water is heated from 25.0 °C to 45.0 °C.
q ≈ 4.18 × 50 × 20 = 4180 J (4.18 kJ)
The bonds that hold atoms together within a molecule
What are intramolecular bonds?
Explain how flame tests can be used to identify metal cations.
Different cations emit characteristic colours due to electron excitation and relaxation.
Activation Energy
The minimum amount of energy that is required for a set of reactants to begin reacting?
This element, with symbol Au, has been used for coins and jewellery for thousands of years.
What is gold?
State the relationship between activation energy and reaction rate.
Lower activation energy → faster rate, because more particles have sufficient energy to react.
A 0.350 g sample of sodium reacts completely with chlorine to form NaCl. Calculate the mass of NaCl produced.
m ≈ 0.89 g NaCl.
A sample of hydrochloric acid solution has a concentration of 0.250 M. What volume (in mL) is required to completely neutralise 25.0 mL of 0.100 M sodium hydroxide?
Volume HCl = n / c = 0.00250 / 0.250 = 0.0100 L = 10.0 mL
A sample of calcium carbonate (CaCO₃, 10.0 g) decomposes completely. Calculate the mass of calcium oxide produced.
m ≈ 5.6 g CaO.
The “father of modern chemistry,” famous for the law of conservation of mass.
Who is Antoine Lavoisier?
For a reaction: ΔH = -125 kJ/mol, ΔS = -220 J/mol·K. Determine if the reaction is spontaneous at 298 K.
ΔG = -125 kJ – (298 × -0.220 kJ) = -59.4 kJ.
Yes, spontaneous.