Science Skills
What is an independent variable in an experiment testing how caffeine affects sleep?
Caffeine intake
What type of graph would best show change in fruit rotting over increasing ethylene amounts?
Line graph
What is the simplest form of matter that cannot be broken down chemically?
Element
A neutral atom has 12 protons. How many electrons and neutrons would it have if its mass number is 24?
12 electrons, 12 neutrons
What is always true about mass in a chemical reaction?
Mass is conserved (stays the same)
What is the name of the following two compounds:
H2O AND CO2
Water and carbon dioxide
Which type of variable stays the same in a fair test? Give an example.
Controlled variable; e.g., volume of liquid used
Give an example of a compound and an element.
Element: oxygen (O), Compound: water (H₂O)
What is meant by a "balanced" chemical equation?
Same number of atoms on both sides of the equation
An atom has 17 protons and 18 neutrons. What is its mass number?
35 (17 + 18)
Balance: ___ H₂ + ___ O₂ → ___ H₂O
2H₂ + O₂ → 2H₂O
What is the name of the compound with the formula NaCl?
Sodium chloride
Rewrite this as a hypothesis: “Caffeine affects reaction time.”
If caffeine is consumed, then reaction time will increase
What variable is written on the X-Axis and Y-Axid
Independent on X
Dependent on Y
Compare the structure of elements and compounds using particle models.
Element = one type of atom; Compound = chemically bonded atoms of different elements
What are the 3 subatomic particles found in an atom?
Proton, neutron, electron
Write the balanced equation for: ___ Fe + ___ O₂ → ___ Fe₂O₃
4Fe + 3O₂ → 2Fe₂O₃
What is the correct name for the compound Ca(NO₃)₂
Calcium nitrate
Describe the correct order of steps in a scientific investigation (Scientific Method).
Ask a question → Form hypothesis → Plan investigation → Collect data → Analyse → Conclude
When drawing a scale on a graph, what are the rules?
Numbers have to increase evenly e.g. 1,2,3 OR 2,4,6 OR 3,6,9 etc.
Even spacing between numbers (e.g, one square space between each number, consistently)
Is CO₂ an element, compound, or mixture? Explain.
Compound – it's made of two elements chemically bonded
What is the name for the center of an atom?
The nucleus
Why do we balance chemical equations? Explain in terms of atoms.
To obey the law of conservation of mass; atoms cannot be created or destroyed
Name the compound P₂O₅ using prefixes.
Diphosphorus pentoxide
Reliability - Are the results repeated and is data consistent across trials
Validity - Does the experiment measure what it intends to measure (appropriate control variables in place)
Accuracy - Is the data close to the theoretical value, and is the equipment used precise enough?
What does the acronym D-TAILS stand for?
D- Data takes up 50% of the graphing area
T- title
A - Axis labels
I- Intervals are evenly space
L- Label the units
S - Scale increases evenly
Identify five groups on the periodic table
Five of the following:
Alkali metals, Alkane Earth Metals, Transition Metals, Metalloid, Metals, Halogens, Noble Gas, Lanthanide, Actinide
An atom has 11 electrons. How many electrons are in each electron shell?
2 in the first shell, 8 in the second shell, 1 in the third shell
___ C₃H₈ + ___ O₂ → ___ CO₂ + ___ H₂O
C₃H₈ + 5 O₂ → 3 CO₂ + 4 H₂O
What is the correct name for the compound N₂O₄?
Dinitrogen tetroxide