Atoms are the fundamental components of all matter. A nucleus is found in every atom. Protons and neutrons make up the nucleus, which is surrounded by one or more electrons. The charge of protons is positive (+). The charge of electrons is negative (-). Neutrons have no electrical charge. Protons and electrons have equal magnitude opposing charges. Protons and neutrons are roughly the same size; however, an electron is significantly smaller.

A chemical compound containing atoms with the same number of protons in their atomic nuclei is known as an element. All compounds have elements as their building blocks. The element's mass number is A. In the nucleus, this is the total number of protons and neutrons. The atomic number is Z. The number of protons in the nucleus is this.

The number of protons in an element defines it. Every element has a specific number of protons. The number of neutrons or electrons in an element might vary, but the element's identity remains the same.

Isotopes are two atoms of the same element with differing mass numbers (different numbers of neutrons). Take, for example, carbon. 12C, 13C, and 14C are the three isotopes of carbon.

There are six protons in each carbon isotope (given the element identified is carbon). There are six neutrons in 12C, seven neutrons in 13C, and eight neutrons in 14C. An atom's atomic weight, or molar mass (M), is measured in atomic mass units (amu). Carbon-12 defines the amu, which is a ratio.

The atomic weight or molar mass of one atom of 12C is 12 amu. This standard is used to compare all other atomic weights. A mole is also defined by 12C. The number of carbon atoms in 12 grammes of 12C is measured in moles. The amount of carbon atoms in 12 g of carbon is 6 x 1023, according to Avogadro's number. In 12 g of 12C, there are 6 x 1023 carbon atoms. The formula that surrounds these concepts is as follows:

n = moles m = mass in grams M = molar mass (found on the periodic table for individual atoms)

Periodic table: The periodic table contains a list of all elements. From left to right, elements are listed according to their atomic number. A group or family is the vertical column of the periodic table, and a period or row is the horizontal row. Periods are numbered 1 to 7, while groups are numbered 1 to 18. The elements are divided into numerous categories in the periodic table above. Different colours in the periodic table above reflect these groupings.

Nonmetals, on the other hand, have lower melting points and produce negative ions.

Nonmetals are used to make most molecular compounds. H2O, for example, is made entirely of nonmetals (oxygen and hydrogen). To produce positive ions, metals lose electrons. Except for mercury, which remains a liquid at ambient temperature, all metals exist as solids.

The transition metals are sometimes left out of group numbers. Groups 1 and 2 are unchanged. Group 13 is referred to as group 3, group 14 as group 4, and so on until group 18, which is referred to as group 8.

When an element has more or less electrons than protons, it is called an ion. Positive ions are called cations, whereas negative ions are called anions. Metals form cations, whereas non-metals form anions.

Atomic size (radius) rises from the top to the bottom and from right to left. This is because as the effective nuclear charge (the number of protons) increases from left to right, each extra electron is drawn closer to the nucleus. Because the atom grows larger with each additional shell, the atomic radius increases from top to bottom.

As you move down the periodic table, you'll see that each underlying period has elements with an extra electron shell. Helium, for example, has one shell and lithium has two.

The energy required to remove an electron from an atom is known as ionisation energy. It takes more energy to remove an electron that is more tightly bonded to the nucleus. Ionisation energy rises from bottom to top and from left to right. From left to right, elements have a higher nuclear charge (more protons). As a result, there are more protons to produce a stronger attraction with the electrons around them, requiring more ionisation energy to remove the electron from the atom. The distance between the nucleus and the electron grows as one moves down the periodic table because there are more electron shells. Because the electric field intensity decreases as distance increases, less energy is required to remove an electron. This explains why as you move up the periodic table, the ionisation energy increases.

An atom's tendency to attract an electron in a bond it shares with another atom is known as electronegativity. From left to right and from bottom to top, electronegativity tends to increase.

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Atoms and molecules summary part 1

Module: General and Organic Chemistry (AOC106DI)

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University: Coventry University

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Atoms are the fundamental components of all matter. A nucleus is found in every atom.

Protons and neutrons make up the nucleus, which is surrounded by one or more electrons.

The charge of protons is positive (+). The charge of electrons is negative (-). Neutrons have

no electrical charge.

Protons and electrons have equal magnitude opposing charges. Protons and neutrons are

roughly the same size; however, an electron is significantly smaller.

A chemical compound containing atoms with the same number of protons in their atomic

nuclei is known as an element. All compounds have elements as their building blocks.

The element's mass number is A. In the nucleus, this is the total number of protons and

neutrons. The atomic number is Z. The number of protons in the nucleus is this.

The number of protons in an element defines it. Every element has a specific number of

protons. The number of neutrons or electrons in an element might vary, but the element's

identity remains the same.

Isotopes are two atoms of the same element with differing mass numbers (different

numbers of neutrons).

Take, for example, carbon. 12C, 13C, and 14C are the three isotopes of carbon.

There are six protons in each carbon isotope (given the element identified is carbon). There

are six neutrons in 12C, seven neutrons in 13C, and eight neutrons in 14C. An atom's atomic

weight, or molar mass (M), is measured in atomic mass units (amu). Carbon-12 defines the

amu, which is a ratio.

The atomic weight or molar mass of one atom of 12C is 12 amu. This standard is used to

compare all other atomic weights.

A mole is also defined by 12C. The number of carbon atoms in 12 grammes of 12C is

measured in moles.

The amount of carbon atoms in 12 g of carbon is 6.022 x 1023, according to Avogadro's

number.

In 12 g of 12C, there are 6.022 x 1023 carbon atoms.

The formula that surrounds these concepts is as follows:

n = moles

m = mass in grams

M = molar mass (found on the periodic table for individual atoms)

Periodic table:

The periodic table contains a list of all elements. From left to right, elements are listed

according to their atomic number. A group or family is the vertical column of the periodic

table, and a period or row is the horizontal row.

Periods are numbered 1 to 7, while groups are numbered 1 to 18.

The elements are divided into numerous categories in the periodic table above. Different

colours in the periodic table above reflect these groupings.

Atoms and molecules summary part 1

General and Organic Chemistry (AOC106DI)

Coventry University

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Atoms and molecules summary part 1

Module: General and Organic Chemistry (AOC106DI)

University: Coventry University

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