Matter & Change
Atomic Structure
Periodic Table
Counting Atoms
Chemistry Challenge
100
What is a pure substance made of only one type of atom
Element
100
What subatomic particle has a negative charge and is found in orbitals/shells?
Electrons
100
What chemical family is very unreactive and have a full outer electron shell?
Noble Gases (Group 18)
100
How many total atoms are in:
H₂O
3
2H + 1O
100
What term describes the ability of a metal to be hammered, pressed, or bent into different shapes
Malleability
200
Salt completely dissolves in water and the mixture looks the same throughout. Classify the final substance as an element, compound, homogenous mixture, or heterogenous mixture
Homogenous Mixture
200
An atom has an atomic mass of 23 and an atomic number of 11. How many neutrons does it have?
12 Neutrons
200
An element is shiny, conducts electricity well, and is found on the left side of the periodic table. What big category does it most likely belong to?
Metals
200
For Na₂CO₃, how many Carbon atoms do I have?
1
200
A student mixes two clear solutions. A cloudy solid suddenly appears and settles at the bottom.
Name the indicator of a chemical change?
Formation of a precipitate
300
A student describes a substance as
- shiny
- melts at 660°C
- reacts with acid
Identify ONE physical property and ONE chemical property
Physical: Shiny/Lustre or Melting Point
Chemical: Reacts with acid
300
Draw the Lewis Dot Diagram for Phosphorus (P)
300
An unknown element is in Group 17.
Predict:
- its family name
- its number of valence electrons
Halogens
7 Valence electrons
300
How many molecules do I have here?
3 Ca(OH)₂
3
300
A student says
"If two substances have the same mass, they must have the same density"
Explain why this statement is incorrect
Density depends on both mass and volume
400
A colourless liquid is heated. Bubbles form, but when the gas cools it becomes the same liquid again. Is this evidence of a physical or chemical change? Explain
PHYSICAL CHANGE
No new substance is formed. Just a change in state
400
An atom contains:
- 17 protons
- 18 neutrons
- 17 electrons
Identify the element AND its atomic mass (whole #)
Chlorine
Atomic mass: 35
400
An unknown element is in Period 3, Group 2
What element is it, and how many electron shells does it have?
Magnesium
3 shells
400
Tell me what elements are present and how many atoms of each:
(CH₃)₂CHOH
C= 3
H= 8
O=1
400
A mystery element:
- conducts electricity
- can be bent without breaking
- has lustre
- reacts strongly with water
- has one valence electron
Which chemical family does it belong to? Explain using 2 pieces of evidence
Alkali metals (Group 1)
- 1 Valence electron
- Very reactive
- Metallic properties
500
A metal sample has a mass of 54g and a volume of 20mL. Calculate its density. Include units
2.7g/mL
500
What atom is this Bohr-Rutherford diagram representing?
Argon
500
An element is in Period 4 and Group 1.
What element is it and describe its properties
Potassium (K)
Properties: Shiny, Silvery, Soft, Highly Reactive
500
A sample contains 3 molecules of Zn(NO3)2
How many atoms of each element?
Zn=3
N=6
O=18
500
A mystery element has:
- 4 electron shells
- 2 valence electrons
- Metallic properties
What element is it, and what family does it belong to?
Calcium (Ca)
Alkaline earth metal