SEMMELWEIS ENTRANCE EXAM CHEMISTRY

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SEMMELWEIS ENTRANCE EXAM CHEMISTRY

CORRECT SOLUTIONS.

The mole concept - correct answer- A method that allows the relative number of reactant particles involved in a chemical reaction to be known

Avogadro's number - correct answer- number of representative particles in a mole, 6.02 X 10^23

Basic structures of atoms - correct answer- There is a nucleus in the center surrounded by an electron cloud or field

Quantum numbers - correct answer- Quantum numbers describe values of conserved quantities in the dynamics of a quantum system. In the case of electrons, the quantum numbers can be defined as "the sets of numerical values which give acceptable solutions to the Schrödinger wave equation for the hydrogen atom"

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Common compounds - correct answer- Water (H2O), table salt (NaCL); carbon dioxide (CO2); baking soda (NaHCO3); carbon monoxide (CO); sand or glass (SiO2)

Periodic properties - correct answer- chemical or physical properties that vary among elements according to trends that repeat as atomic number increases

What are the periodic properties? - correct answer-

Element (on periodic table) - correct answer-

Atomic number is the same as - correct answer- number of protons

Atomic mass is the same as - correct answer- Number of protons and neutrons

Different types of chemical bonding - correct answer- metallic, covalent, ionic

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What is covalent bonding and how does it work? - correct answer- when atoms share one or more pairs of electrons.They have similar electronegativities

What is ionic bonding? - correct answer- when atoms transfer electrons. Large difference in electronegativity

Examples of ionic bonds - correct answer- NaCl Cs2O MgO

NH4NO3

Examples of covalent bonds - correct answer- F2, O2, N2, H2,

CL2, HCL, H2O

What is metallic bonding? - correct answer- the chemical bonding that results from the attraction between metal atoms and the surrounding sea of electrons

What is hydrogen bonding? - correct answer- Hydrogen bonding is the strongest intermolecular force. it only happens

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