pH Scale
How many numbers are on the pH scale?
Fourteen
How many elements have been discovered?
118 elements have been discovered.
What is a mixture?
A mixture is a blend of two or more substances.
What is a heterogeneous mixture?
A heterogeneous mixture is a mixture that has separated or unevenly distributed components.
What are crystals?
Crystals are solids that have a repeating molecular structure.
Is black coffee acidic or basic?
Black coffee is acidic.
What is an element?
An element is a pure substance in which all atoms are the same.
What is an example of a homogeneous mixture?
Could be various things (i.e. blood, hot chocolate, or the mixture of gases in the air).
What are physical changes?
A physical change occurs when a physical property in a substance changes without the addition of another substance or chemical reaction.
What are the three most common ways that crystals form?
Crystals can form when magma cools, water cools, or when water evaporates.
What is milk rated on the pH scale?
Milk is rated 6 on the pH scale.
What is included in each element's square?
The name, symbol, atomic number, and atomic mass of an element is located in its square.
What is a chemical reaction?
A chemical reaction is a process in which two or more pure substances join their molecules to create a compound with different properties.
What are chemical changes?
A chemical change occurs in a chemical reaction or when any chemical property in a substance is altered. They often create new substances and are irreversible.
Why can crystals be made of washing powder, sugar, or salt?
Crystals can be made of washing powder, sugar, or salt because they consist of many, miniscule crystals.
What characterizes the behavior of an acid?
How many periods are in the periodic table?
Seven periods are in the periodic table.
What are the two parts in a chemical reaction?
A chemical reaction begins with reactants whose molecules collide to create the product.
What are evidence of chemical reactions?
Production of gas, light, heat, precipitate, or odours, and changes in colour or temperature are evidence of chemical reactions.
Why do crystals form on a string or stick when water evaporates or cools?
Crystals form on the stick or string because their molecules are attracted to it by electric charges.
Name a substance that has a pH of 14.
Drain Cleaner
Who created the periodic table and when?
Dmitri Mendeleev created the periodic table in 1869.
How do you you increase reaction rates?
You can increase reaction rates by adding heat, energy, pressure, or more of the reactants.
What is a catalyst?
Catalysts are substances that help chemical reactions occur effectively by providing an alternative path for the process or decreasing the activation energy.
How many lattices (kinds of shapes) do crystals form?
Crystals form seven lattices.