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Simplified Chemistry

Mole and chemical formulas

Because the individual atoms in a compound are combined in integer ratios, and each element has a specific atomic mass, it is possible to use mole calculations to determine chemical formulas. The two types of chemical formulas are molecular formulas and the empirical formulas. – Often, the empirical formula is …

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The Mole Concept

The concept of mole is extremely useful in chemistry. The mole is a term like dozen. Dozen means 12. The mole means 6.02 x 1023. It is convenient for chemists to use a concept like mole which represents such a large number since they deal in very small and very …

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Chemical Formulas

There are two types of compounds: molecular and ionic compounds. For molecular compounds, a molecular formula represents the number and kinds of atoms in the molecule. The molecular formula also tells us the lowest whole number ratio between the atoms in the compound. For example, water is represented by the …

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compounds

Compounds Compounds are pure substances that differ from elements because they contain more than one kind of atom. The Law of Definite Composition (or the Law of Definite Proportions) applies to compounds. For example, sodium chloride contains one atom of sodium for each atom of chlorine. Water contains two atoms …

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isotopes and isobars

Isotopes: Isotopes are atoms of the same element having the same atomic number but different atomic masses. Note that the difference in the masses of isotopes is due to the different number of neutrons in their nuclei. Isotopes have the same chemical properties . because they have the same number of …

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Structure of the Atom

Each atom is made up of an inner core called the nucleus.  – Most of the atom’s mass is located in the relatively small nucleus.  – The rest of the atom is comprised of a relatively large region outside the nucleus where the electrons are found. – The atom is …

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Atomic Theory

Dalton’s Model of the atom. It is the basis of our understanding of the nature of matter. The following four statements comprise Dalton’s Model: a –  All matter is made up of extremely tiny. particles. called atoms. b-  Atoms are indivisible. c – Atoms of the same element are alike. …

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