Everything is made Atoms
What is the smallest unit of an element that retains the properties of that element?
Atom
What information is found in each box of the periodic table?
atomic number (number of protons), atomic symbol (a one- or two-letter abbreviation), element name, and atomic mass (average atomic weight)
What is an endothermic reaction?
a chemical process that absorbs energy, typically in the form of heat, from its surroundings, causing the surroundings to cool down
Bonus 300 points: Show the movement to remember an endothermic reaction
What is a physical change?
a type of change where a substance alters its physical properties—such as its state, shape, size, or color—but its chemical composition and identity remain the same
What does pH measure?
the acidity or alkalinity of an aqueous (water-based) solution by indicating the concentration of hydrogen ions (H+) it contains.
What particles make up an atom, and what are their charges?
Proton +
Neutron 0
Electron -
What are the three main categories of elements in the periodic table?
metals, nonmetals, and metalloids
What is an exothermic reaction?
a chemical process that releases energy into its surroundings, typically as heat, causing the surroundings to feel hotter
What is a chemical change?
a process, also called a chemical reaction, where atoms and molecules rearrange, breaking chemical bonds and forming new ones to create at least one new substance with entirely different properties from the original
What is the pH scale range, and what do the values represent?
0 to 14, measuring the acidity or basicity (alkalinity) of a solution based on its hydrogen ion concentration
What is the difference between isotopes of an element?
They have different neutrons
Bonus 500: What happens to an atom's charge when it loses an electron?
How are elements arranged in the periodic table?
By atomic number
Bonus 500: Do your best Jet 2 Holiday impression
How can you tell if a reaction is endothermic or exothermic based on temperature change?
by observing the temperature change of the surroundings:
Provide an example of a physical change and a chemical change.
When an ice cube melts, it changes from a solid to a liquid, which are different physical states, but the substance is still water (H₂O). Other examples include chopping wood, tearing paper, and boiling water.
Burning a piece of paper is a chemical change because the paper reacts to form new substances, such as ash, carbon dioxide, and water. Other examples include cooking an egg, rusting iron, and digestion.
Give an example of something that is acidic.
Lemons, vinegar, pickle juice, etc.
Bonus 400: Don't crash out and say the range of acids on the pH scale.
How do atoms bond to form molecules?
by creating chemical bonds through the interaction of their outermost electrons, called valence electrons
What are alkali metals, and where are they located on the periodic table?
elements in Group 1 of the periodic table, located in the far-left column
Give an example of an everyday endothermic reaction.
cooking an egg, the baking of bread, and photosynthesis by plants, the melting of ice
How can you tell if a chemical change has occurred?
if you observe a new substance forming, indicated by clues such as a color change, the production of a gas (like bubbles or fizzing), a change in temperature (heat or cold), the formation of a precipitate (a solid from liquids), or the release of light or sound. An odor change
What is a neutral pH, and what substances have this pH?
a pH of 7, indicating a balance between acidity and alkalinity. The most common substance with a neutral pH is pure water
Explain the concept of atomic mass and how it is calculated
the weighted average mass of an element's atoms, calculated by multiplying the mass of each isotope by its fractional abundance and summing these values
Where are noble gases located?
Far right of the table
Bonus 200 points: Name a noble gas
How do endothermic and exothermic reactions relate to energy changes in chemical reactions?
Endothermic reactions absorb energy from their surroundings, leading to a net decrease in the system's energy and often a cooling effect, while exothermic reactions release energy into the surroundings, resulting in a net gain of energy by the system and a warming effect
Explain how the law of conservation of mass applies to physical and chemical changes.
in a closed system, the total mass of reactants equals the total mass of products in both chemical changes and physical changes, meaning matter is neither created nor destroyed, only transformed
An unknow substance has a pH of 10. Is it acidic or basic/alkaline?
Alkaline
Bonus 300 points: You'll be cooking if you can say the range of the base scale on the pH table.