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Chapter

Cover Making the Transition to University Chemistry

Moles  

This chapter explores different types of formulae in chemistry: empirical formula and molecular formula. It defines empirical formula as the simplest whole-number ratio of atoms of each element in a compound. Molecular formula can be defined as the whole-number multiple of the empirical formula. The chapter also explains the value of the Avogadro constant, which is the number of atoms per mole. It notes the strategies for solving mass-to-mass calculations, ideal gas models, molar concentration, and molar volume. Molar mass is defined as the mass per mole of a substance. A solution is mostly expressed through mass concentration. This specifies the mass of the solute dissolved per cubic decimetre of the solution.

Chapter

Cover Making the Transition to University Chemistry

Instrumental Analysis  

This chapter expounds on the types of instrumental analysis used in chemical laboratories, especially those working with organic compounds. It also notes the fragmentation patterns that characterize a molecule. Mass spectrometry is utilized to search for a compound's molecular formula, while infrared spectroscopy involves the absorption of radiation in the electromagnetic spectrum's infrared region. The energy absorbed makes the bonds vibrate more energetically. Nuclear magnetic resonance (NMR) spectroscopy calculates nuclei's protons and neutrons that possess nuclear spins. The chapter also explains the process of spin-spin splitting or coupling in the NMR spectra as it depends on the number of adjacent protons.

Chapter

Cover Atkins’ Physical Chemistry

The internal energy and the entropy  

This chapter considers the molecular interpretation of thermodynamic properties, especially concerning internal energy and entropy. Any thermodynamic function can be obtained after the identification of the partition function. Moreover, the calculation of derived functions, like Gibbs energy, will be possible following the identification of internal energy and entropy. The chapter covers the calculation of internal energy, referencing that the total heat capacity of a molecular substance is the sum of the contribution of each mode. It discusses statistical entropy being defined by the Boltzmann formula and expressed through molecular partition function, while residual entropy refers to a non-zero entropy from molecular disorder.