Atomic Structure
This sub-atomic particle determines the identity of an element.
What is a proton?
This type of mixture has parts you can see easily and separate, like a salad.
What is a heterogeneous mixture?
Two atoms bonded together is called this.
Answer: What is a molecule?
Bubbles forming in a mixture is evidence that this has occurred.
Answer: What is a chemical reaction?
The center of the atom is called this.
Answer: What is the nucleus?
This is the charge of an electron.
What is negative?
Salt water is this type of mixture because the components are evenly distributed.
What is a homogeneous mixture?
Water (H₂O) is this type of substance because it contains hydrogen and oxygen atoms bonded together.
Answer: What is a compound?
A sudden temperature change during mixing is a sign that this type of change is happening.
What is a chemical change/reaction?
This particle moves around the nucleus in energy levels or shells.
What is an electron?
If an atom gains two electrons but keeps the same number of protons and neutrons, this is its' charge.
What is 2 - ?
An element made of atoms bonded in pairs, like O₂ or N₂, is called this.
What is a molecular element?
We used this simulation to build molecules during class.
What is PHET “Build a Molecule”?
A solid that forms when two solutions are mixed is called this.
What is a precipitate?
Explain why salt water is not a pure substance.
Answer: It contains two substances physically mixed (salt + water) and can be separated
This is the difference between an element and a compound.
An element is made of one type of atom; a compound has two or more elements chemically bonded.
Molecules can have different shapes. This helps explain why some smell strong—this is the lab we ran about scent.
What is the odour lab?
List two signs that a chemical reaction has taken place.
Answer: Any two: colour change, gas produced, temperature change, new odour, precipitate, light produced.
Why does increasing temperature make reactions happen faster?
Particles move faster, causing more collisions with enough energy.
Changing the number of these two particles changes an atom's mass AND its charge without changing the type of element.
What are neutrons and electrons?
This term describes a substance made of two or more elements physically combined, not chemically bonded.
What is a mixture?
This is the reason carbon dioxide (CO₂) is a compound but oxygen (O₂) is not.
CO₂ has two different elements; O₂ has only one element.
In our reaction-identification lab, this type of evidence helped us determine if gases were produced.
Answer: Formation of bubbles (effervescence).
This is the difference between a chemical change and a physical change.
A chemical change forms a new substance; a physical change does not.
Describe what happens to an atom’s overall charge if it has 11 protons and 10 electrons, and explain why.
It becomes +1 because it has one more proton (positive) than electron (negative).
Explain why a compound cannot be separated by physical methods, but a mixture can.
Compounds have chemical bonds between elements; mixtures do not, so components can be separated physically.
Explain why molecular shape can affect a molecule’s smell, referring to how receptors in the nose detect molecules.
Answer: Molecules must match the shape of scent receptors; different structures fit differently, producing different smells.
Explain why a temperature increase during a reaction indicates that bonds are breaking and forming at the particle level.
Breaking and forming bonds releases or absorbs energy; if temperature increases, energy is released (exothermic reaction).
Explain how particle motion, atomic structure, or molecular shape connects two different topics from this unit.
motion affects reaction rate, while atomic structure determines how atoms bond, which affects molecular shape.