What is the difference between an element and a compound?
Compounds are made of 2 or more elements
Elements can't be broken down
A student observes a solid, and notes that it looks bright yellow, is very hard, and not shiny. What type of properties did the student observe, chemical or physical?
Physical
Are particles in a gas close together, somewhat spread out, or very far apart?
Very far apart
What were the four greek elements? (Hint, avatar!)
Fire, Earth, Air, and Water
Which chemical family contains the elements Li, Na, K, Ru and Cs?
The Alkali Metals
Is Kool Aid an element, compound, heterogeneous mixture, or homogeneous mixture?
A homogeneous mixture
A student tries to pour honey out of a jar and notices that it flows very slowly.
What is the name for this property, and is it physical or chemical?
Viscosity, and it is physical
Which state of matter (in general) has the lowest amount of energy?
Solids
What is the name of the element that has the symbol Br on the periodic table?
Bromine
Which chemical family does not react at all, is tasteless, colourless, odourless, and non toxic?
The Noble Gasses
If a nickel coin is melted down into a liquid, is this liquid an element, compound, homogeneous mixture, or heterogeneous mixture?
Element - melting it does not change it chemically.
A student roasts marshmallows over a campfire to make smores.
What type of change is this? Physical or chemical?
Which state of matter has particles moving somewhat quickly, and are somewhat spread out?
A liquid
What is the chemical symbol for the element Gold?
Au
A scientist discovers a new element! This element reacts violently with water, and is soft, and can be cut with a knife. What family does this new element likely belong to?
The Alkali Metals
A student mixes two chemicals. Afterwards, they observe a bright blue solid powder floating in a clear liquid.
Is this an element, a compound, a homogeneous mixture, or a heterogeneous mixture?Heterogeneous mixture - two distinct phases.
Iodine is called a "volatile" solid. At room temperature, the solid crystals slowly turn into a bright purple gas.
What is this transition directly from solid to gas called? Is this process a physical, or chemical change?
Sublimation
Physical change - the iodine is changing state but its chemical properties are the same.
Why does dew on the grass in the morning eventually go away by the afternoon?
Use Kinetic Molecular Theory to explain
Some particles in the liquid dew have enough energy to become a gas and evaporate.
When the sunlight hits the dew, it gives it enough energy for the remaining water to move faster and turn into a gas and evaporate.A scientists discovers a new element! It is dull, has a low melting point, and does not conduct heat or electricity.
Is this new element likely a metal, non-metal, or metalloid?
non-metal
Is the cooking of pancakes on the stove a chemical property, physical property, chemical change, or physical change?
A chemical change
Carbon dioxide can be written as CO2 . It consists of one carbon atom (an element), and two oxygen atoms (also elements) stuck together. It is used to make fizzy drinks!
Is carbon dioxide an element, compound, homogeneous mixture, or heterogeneous mixture?
A compound - it is made of two different kinds of elements
Hair spray is flammable. If hair spray is heated, it can explode.
Is the burning of hair spray a chemical change a physical change, a chemical property, or a physical property?
The ability to burn (flammability) is a chemical property but actually burning the hair spray is now preforming a chemical change to the hair spray itself.
A dented basketball can be fixed (reinflated) by placing it in a tub full of hot water.
How can kinetic molecular theory help us explain why this happens?
The gas particles in the basketball move faster when they are heated (they gain energy) and spread out and push against the outside of the ball.
This pushing against the ball causes the ball to "reinflate" again. (but when the ball cools, it can deflate! Temporary fix)
What is the name of the scientist who developed the first modern periodic table? (Hint, we learned about him from the movie, and he is Russian!)
Dimitri Mendeleev
How many elements naturally occur on earth? Did scientists know about every element when the periodic table was first created?
92
No, many elements were not discovered yet