Unit 1: Atomic Structure and Properties.

1.1 Moles and Molar Mass.

Apply Avogadro’s number to calculate the number of moles given the number of particles (atoms, molecules, formula units, ions) in a substance and vice versa.

  1. How many moles are in 3.01x1023 molecules of CO2?

Understand that the mass of a single atom in amu is numerically equalivant to the mass of a mole of that substance in grams.

  1. The mass of a single molecule of methane (CH4) is 12.04 amu. What is the molar mass of methane?

Use molar mass to convert between mass and moles of a substance.

  1. How many moles are in 25.0 g of H2O?

Use subscripts to convert between molecules and the number of atoms of a given element.

  1. How many hydrogen atoms are in 2 molecules of NH3?

1.2 Mass Spectra of Elements.

Identify an element given its mass spectrum.

  1. What element is represented by the mass spectra?
    2. Mass spectrum example

Calculate the average atomic mass of an element given its mass spectrum.

  1. What is the average atomic mass of the element depicted in the mass spectrum below?
    Mass spectrum of Neon

1.3 Elemental Composition of Pure Substances.

Determine the empirical formula of a compound given data.

  1. A compound contains 40.0% carbon, 6.7% hydrogen, and 53.3% oxygen by mass.What is its empirical formula.

Apply the Law of Definite Proportions to determine the ratio of atoms in a compound when given mass amounts.

  1. How many grams of Oxygen (O) are in a 36 g sample of water (H2O)?

Determine the measurements/steps needed to determine the formula of a compound in the lab (gravimetric analysis).

  1. Magnesium metal (Mg) reacts with oxygen gas (O2) to form magnesium oxide (MgxOy) when heated. Use the lab data to determine the empirical formula of magnesium oxide. Mass of sample before heating : 1.00g, Mass of sample after heating: 1.66g.

1.4 Composition of Mixtures.

Compare and contrast pure substances and mixtures.

  1. Classify the following as a pure substance or mixture: (a) salt water (b) gold (c) air.

Perform calculations to determine the formula and/or purity of a compound by calculating/comparing relative amounts.

  1. A mixture of magnesium oxide (MgO) and sodium oxide (Na2O) contains the 25.0% Mg, 43.4% Na and 31.6% O. What percent by mass of the mixture is MgO?

1.5 Atomic Structure and Electron Configuration.

Identify the location of subatomic particles and the charge of areas of the atom.

  1. Summarize the location, charge, and relative mass of the subatomic particles.

Understand and apply the terms: shell (or energy level), subshell (or sublevel), and orbital in reference to the quantum mechanical model.

  1. Describe the atomic structure of Neon (Ne) using the terms: shell, subshell, and orbital.

Qualitatively apply Coulomb’s law and effective nuclear charge to justify differences in attractive force between nucleus and core vs. valence electrons.

  1. Why are valence electrons easier to remove than core electrons?

Write the electron configuration for an atom or ion.

  1. Write the electron configuration for Cl
  2. Write the electron configuration for O2-.
  3. Write the electron configuration for Mn2+

Determine the number of unpaired electrons in an atom.

  1. How many unpaired electrons are in a nitrogen atom?

Differentiate electronic structure in terms of shells and subshells.

  1. What is the difference between the 2s and 2p subshells in terms of energy and shape?

Qualitatively apply Coulomb’s law to discuss differences in ionization energy by comparing electron shells/subshells between atoms.

  1. Why does lithium (Li) have a higher ionization energy than potassium (K)?
  2. Why does lithium (Li) have a lower ionization energy than nitrogen (N)?

1.6 Photoelectron Spectroscopy.

Identify an element based on its PES (Photoelectron Spectroscopy).

  1. Identify the element shown in the PES below

    2. PES of a unkown element

Label the peaks on a PES spectrum with the corresponding subshell.

  1. In a PES spectrum of oxygen below , label which peaks correspond to 1s, 2s, and 2p electrons. PES of a unkown element 2p,2s,1s

    2. PES of a unkown element

Compare heights of peaks in the spectrum to determine the number of electrons in a subshell.

  1. If the 2p peak is three times the height of the 2s peak in a PES spectrum, how many electrons are in each subshell?

Explain differences between PES spectra of two atoms/ions.

  1. How would the PES spectrum of Na differ from that of Na+?

1.7 Periodic Trends.

Apply Coulomb’s Law and atomic structure features to compare atomic properties between two elements.

  1. Explain why fluorine has a smaller atomic radius than oxygen.

Use periodicity to predict or estimate values of properties of elements.

  1. Which element has a higher first ionization energy: Na or K?

1.8 Valence Electrons and Ionic Compounds.

Predict the type of bond that will form between two atoms based on their valence electrons.

  1. What type of bond is expected between magnesium and chlorine?

Choose a compound with similar properties to a given compound based on periodicity.

  1. Which compound has properties most similar to NaCl: KCl, CaCl2, or ClF?

Predict the charge on an atom by its location on the periodic table.

  1. What charge does a calcium atom form when it becomes an ion?
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