Atoms

Question 1

What are atoms

Answer 1

Atoms are the basic building blocks of matter and are composed of three primary subatomic particles: protons, neutrons, and electrons.

Question 2

What are atoms made of

Answer 2

Protons:
Charge: Positive (+1).
Location: Found in the nucleus (the center) of the atom.
Mass: Approximately 1 atomic mass unit (amu).
Role: The number of protons in an atom determines the element’s identity (e.g., hydrogen has 1 proton, helium has 2).
Neutrons:
Charge: Neutral (0).
Location: Also found in the nucleus of the atom.
Mass: Approximately 1 amu (slightly more than a proton).
Role: Neutrons contribute to the atomic mass and stability of the nucleus. Different numbers of neutrons in the same element create isotopes.
Electrons:
Charge: Negative (-1).
Location: Orbiting the nucleus in electron shells or energy levels.
Mass: Much smaller than protons and neutrons (approximately 1/1836 amu).
Role: The number of electrons determines the atom’s overall charge and its chemical behavior.

Question 3

What is a compound

Answer 3

Compounds are substances formed when two or more elements chemically combine in fixed ratios. Examples include:
Water (H₂O): Composed of hydrogen and oxygen.
Carbon Dioxide (CO₂): Composed of carbon and oxygen.
Sodium Chloride (NaCl): Common table salt, composed of sodium and chlorine.

Question 4

What is a mixture

Answer 4

Mixtures consist of two or more substances that are physically combined but not chemically bonded. They can be homogeneous (uniform composition) or heterogeneous (distinct, separate components). Examples include:
Air: A homogeneous mixture of gases.
Salad: A heterogeneous mixture of various vegetables.
Sand and salt: A mixture that can be separated by physical means.

Question 5

What is an element

Answer 5

Elements are pure substances that cannot be broken down into simpler substances by chemical means. Each element is defined by its atomic number (number of protons).
Examples include:
Hydrogen (H)
Oxygen (O)
Gold (Au)
Carbon (C)
There are currently 118 known elements, organized in the periodic table.

Question 6

how to Find the Number of Protons, Neutrons, and Electrons

Answer 6

Number of Protons:
The number of protons in an atom is equal to the atomic number of the element. You can find the atomic number on the periodic table.
Trick: Look for the element symbol and find its corresponding atomic number. For example, carbon (C) has an atomic number of 6, meaning it has 6 protons.
Number of Electrons:
In a neutral atom, the number of electrons is equal to the number of protons. If the atom is an ion (charged), you need to consider the charge.
Neutral Atom: Electrons = Protons.
Positively Charged Ion (Cation): Electrons = Protons - Charge.
Negatively Charged Ion (Anion): Electrons = Protons + Charge.
Trick: For neutral atoms, just remember that the number of electrons equals the atomic number.
Number of Neutrons:
The number of neutrons can be found using the formula: Number of Neutrons = Atomic Mass - Atomic Number
The atomic mass is usually a decimal number found on the periodic table, representing the weighted average of all isotopes of the element.
Trick: Round the atomic mass to the nearest whole number to get the mass number (total of protons and neutrons), then subtract the atomic number (protons) to find the number of neutrons.

Question 7

Example:

Answer 7

Atomic Number: 6 (from the periodic table, so it has 6 protons).
Atomic Mass: Approximately 12 (rounded from 12.01, so the mass number is about 12).
Electrons: In a neutral carbon atom, it has 6 electrons.
Neutrons: Using the formula: [ \text{Number of Neutrons} = 12 - 6 = 6 ] Thus, a neutral carbon atom has 6 protons, 6 electrons, and 6 neutrons.

Question 8

Summary

Answer 8

Protons = Atomic Number (found on the periodic table).
Electrons = Protons (for neutral atoms) or adjusted for charge (for ions).
Neutrons = Atomic Mass (rounded) - Atomic Number.