What are atoms made of?

Atoms are composed of a core containing protons and neutrons, surrounded by electrons.

How do elements differ in the periodic table?

Elements in the periodic table vary by the number of valence electrons.

Water is a polar molecule due to electronegativity differences.

Chemical bonds include covalent, ionic, and metallic bonds.

Catalysts reduce activation energy for faster reactions.

The number of protons in an atom defines its elemental identity, with elements arranged in the periodic table based on their valence electrons, leading to similar chemical behaviors within groups, except for helium.
Chemical reactions aim to achieve stability, requiring balancing based on stoichiometry and conservation of mass, with catalysts reducing activation energy, and enthalpy and Gibbs Free Energy determining reaction spontaneity, while equilibriums involve reversible reactions with constant concentrations.

What are atoms made of?
Atoms are composed of a core containing protons and neutrons, surrounded by electrons.
How do elements differ in the periodic table?
Elements in the periodic table vary by the number of valence electrons.
What determines the polarity of water?
Water is a polar molecule due to electronegativity differences.
What are the different types of chemical bonds?
Chemical bonds include covalent, ionic, and metallic bonds.
What role do catalysts play in chemical reactions?
Catalysts reduce activation energy for faster reactions.

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Atoms are composed of a core with protons and neutrons, surrounded by electrons.
The number of protons in an atom determines the element it is.
Elements are listed in the periodic table, with each element having a specific number of valence electrons.
Elements in the same group have the same number of valence electrons, except for helium which has 2.
Elements with the same number of valence electrons exhibit similar chemical behavior.
Atoms with the same number of electrons and protons are neutral, while those with more or less are ions.
Different types of bonds include covalent, ionic, and metallic bonds, each with distinct characteristics.
Water is a polar molecule due to the electronegativity difference between hydrogen and oxygen.
Intermolecular forces like hydrogen bonds and Van der Waals forces play a role in molecular interactions.
Chemical reactions occur to reach a more stable state, with reactions needing to be balanced based on stoichiometry and conservation of mass.

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To balance a chemical reaction, start with metals, then nonmetals, and end with hydrogen and oxygen, using trial and error until balanced.
To ensure the correct ratio of reactants in a lab, look up the atomic mass of each and use that amount in grams to get the right number of particles.
Differentiate between physical and chemical changes, with reactions only occurring in the latter, often accompanied by bubbles, smells, or explosions.
All chemical reactions require activation energy, with catalysts reducing this energy needed for reactions to occur faster and easier.
Enthalpy measures the internal energy or heat content of a system, determining if a reaction is exothermic (heat released) or endothermic (heat absorbed).
Gibbs Free Energy considers enthalpy and entropy changes, determining if a reaction is spontaneous (exergonic) or not (endergonic), dependent on temperature.
Chemical equilibriums occur in reversible reactions where concentrations remain constant, often seen in phase changes and acid-base chemistry.
Understanding redox reactions involves knowing oxidation numbers, with rules for assigning them and balancing charges in acidic or basic solutions.