Name This Reaction
Periodic Table
Chemical and Physical Changes
Miscellaneous
100
Fill in the blank
2H2 + ___ -> 2H2O
Bonus Point if you can tell me how many of the mystery particle is needed, and what conservation law needs to be followed.
O2
2H2 + O2 -> 2H2O
Bonus points for diatomic Oxygen, and Law of Conservation of Mass
100
True or False: All particles are atoms but not all atoms are particles.
False, all atoms are particles, not all particles are atoms.
100
Do chemical changes form new substances?
Yes
100
Is Chlorophyll green in all plants?
No.
While chlorophyll is responsible for the green in most plants, not all plants contain the same type of chlorophyll. The structure can be different - making different colours, or some plants like red cabbage can have different pigments (anthocyanin) that can give them a red, purple, or yellow hue.
200
What is the only state of matter that can be compressed?
Gas
200
What is the correct way to write the chemical symbol for Iron.
a) Ir b) Fe c) FE d)fe
b) Fe
200
What does the law of conservation of mass state?
That matter can neither be destroyed or created - but can be rearranged into new substances.
200
How many weekends in a row have we had thunderstorms in SE Queensland?
Hint: Answer is between 0-10
5 Weekends (Isn't that crazy)
300
Write a reaction for freezing water?
Water(l) - heat -> water(s)
300
What is the term for a solid that dissolves in a liquid to form a solution?
Solute
300
Which of the following observations would NOT be considered a sign of a chemical change?
A) noticing a solid forming
B) seeing a substance catch fire
C) cutting a solid into smaller pieces
D) seeing permanent colour change
C) Cutting a solid into smaller pieces.
This is a physical change because no new substances are created.
300
Would you use a metal or non-metal for the following applications:
a) the element in a heater
b) a fishing rod
c) an oven mitt
a) metal - it needs to conduct electricity and heat
b) non-metal - it needs to be light and flexible (not bend permanently)
c) non-metal - it should not conduct heat
400
HCl + Mg -> MgCl + H2
Name all the reactants and products.
Bonus marks if you can balance the equation (write down complete balanced equation)
HCl + Mg -> MgCl + H2
Hydrochloric acid + Magnesium -> Magnesium Chloride + Hydrogen (gas)
Bonus:
2HCl + 2Mg -> 2MgCl + H2
400
Can a compound exist in a mixture? Explain.
Yes, it is only if the compounds are not chemically bonded that it is considered a mixture.
400
Why is cooking an egg a chemical change?
Cooking an egg is a chemical change because proteins denature and new substances form; it’s irreversible.
400
Name a cool weather fun fact:
Coolest fact gets bonus points
Answers can include:
Flash-Bang effect
Can tell age of Hail from concentric circles
Can tell the temperature by counting cricket's chirps
There are approximately 20000 thunderstorms in progress worldwide at any given time
Other planets in our solar system also have lightning, including gas giants Jupiter and Saturn. There are also bright flashes in dust storms on Mars, which some scientists believe to be evidence of lightning.
500
Name this reaction?
Elephant Toothpaste
2H2O2 -> 2H20 + 02
(Hydrogen peroxide -> water + oxygen)
500
Explain why a gas being produced is not always a sign that a chemical change is taking place.
It might also be a physical change such as evaporation or sublimation.
500
If salt dissolves in water and the mixture looks different... is it a physical or chemical change? and how can you prove the change?
Salt-Water is a Physical Change.
You can evaporate the water and recover the salt, showing that no new substance was created — just a mixture formed.
500
Answer one of the following questions:
Where was Helium first discovered (not on Earth)?
Approximately when was it first observed? Write to the closest 100's (eg 1600's)
(no marks deducted for this question, if both correct, then bonus marks will be awarded)
Helium was first discovered in the Sun in 1868 (1800's).
It was identified with a yellow spectral line observed during solar observations.