Physical/Chemical Changes
Lina left apples in a bowl for a week and they turned soft and brown; new materials with different characteristics formed. What happened?
the apples decayed (a chemical change)
Marco has magnets on toy train cars; which pole of one car will attract the opposite pole of another car?
the South pole attracts the North pole
Ryan needs boxes that take up the most space for a van. Which tool would best measure this directly?
a tape measure to find volume
In the Boat Distances table, which size boat consistently traveled the farthest distance?
Trial 1
Boat 1: 456 m
Boat 2: 567 m
Boat 3: 662 m
Trial 2
Boat 1: 422 m
Boat 2: 547 m
Boat 3: 609 m
Trial 3
Boat 1: 448 m
Boat 2: 573 m
Boat 3: 611 m
Boat 3
Which sport needs solid water (ice) as the surface?
ice curling
ice skating
snowboarding/skiing
Nia placed steel wool in vinegar; it turned reddish‑brown and flaky. What happened?
It rusted
Jordan found items stuck to a magnet in a backpack; which of these items is most likely attracted: iron paperclip, aluminum sharpener, or brass key?
the iron paperclip
A habitat for a frog is filled with 20 grams of pebbles, 10 grams of sand, and 100 grams of dirt. After 5 days what will the mass of the habitat be?
equal to the mass of the sum of the parts
From the Moving Water table, increasing water amount from 10 gallons to 20 gallons caused the logs to do what?
Trial 1: 10 gallons
Log 1: 5 m
Log 2: 6 m
Log 3: 4 m
Trial 2: 15 gallons
Log 1: 10 m
Log 2: 11 m
Log 3: 13 m
Trial 3: 20 gallons
Log 1: 15 m
Log 2: 16 m
Log 3: 15 m
move farther (greater distance)
Which sport requires liquid water as the surface?
barefoot water skiing
swimming
Students made a sandwich using 20 grams of bread, 10 grams of meat, and 5 grams of cheese. They cooked the sandwich and wondered about the mass. What will happen to the mass?
The mass stays the same as the sum of the parts
During a strong storm, a frisbee was blown onto a roof. Which form of energy caused the frisbee to move?
the energy of motion from the moving air
Students measured the time for a toy car down a ramp; which variable is most likely causing differences when every group used the same ramp and car but different people released it?
inconsistent starting method (different person releasing the car)
Drew put steel wool into different liquids and recorded the temperature. What claim can this data support?
Steel wool in water: 77 degreesSteel wool in Oil: 79 degrees
Steel wool in vinegar: 80 degrees
Different liquids can create different temperatures. Vinegar has the highest temperature and water has the lowest.
In a glass bottle, water droplets formed on the inside around the top. What is this called?
water vapor (gas) condensed to liquid
Kristen noted the steel wool in vinegar changed color, texture, and odor — which of these best indicates a chemical change?
The color change to reddish‑brown (or odor change)
Marlowe tosses a magnet into a school bag; which combination below contains mostly magnetic materials: iron paperclip, nickel hair clips, steel toy car; OR aluminum pencil sharpener, brass key?
iron paperclip, nickel hair clips, steel toy car
In the Car Racing table, which tire pressure had the greatest speed?
Car 1: 12 psi
Car 2: 15 psi
Trial 1: 12 psi 6.0 seconds 15 psi 4.0 seconds
Trial 2: 12 psi 5.0 seconds 15 psi 3.0 seconds
Trial 3: 12 psi 5.1 seconds 15 psi 2.0 seconds
Trial 4: 12 psi 6.3 seconds 15 psi 2.5 seconds
Trial 5: 12 psi 6.0 seconds 15 psi 2.2 seconds
15 psi because it has the lowest time
In the tire test, Sean claims that trial 3 had the fastest speed. What evidence supports this claim?
Car 1: 12 psi
Car 2: 15 psi
Trial 1: 12 psi 6.0 seconds 15 psi 4.0 seconds
Trial 2: 12 psi 5.0 seconds 15 psi 3.0 seconds
Trial 3: 12 psi 5.1 seconds 15 psi 2.0 seconds
Trial 4: 12 psi 6.3 seconds 15 psi 2.5 seconds
Trial 5: 12 psi 6.0 seconds 15 psi 2.2 seconds
Trial 3 has the lowest number of seconds for car number 2
Why is melting the chocolate a physical change and not chemical?
because chocolate changed state (solid → liquid) but did not form new substances
Give two observable signs from experiments that help distinguish a physical change from a chemical change.
changes in state, shape, or size (physical) versus new color, odor, gas production, or new material formed (chemical)
List 3 magnetic metals
Iron, nickel, steel, cobalt
Which physical property changes when the car’s tire air pressure is changed
C. Mass and volume changed when more air was added.
Give two reasons repeating trials improves experimental reliability.
Repeating trials prevent false results due to errors in experiments.
It gives scientist the most accurate results.
It leaves room for mistakes.Name the states of matter in order according to this scenario:
1. Lily poured a glass of lemonade into a cup.2. She then poured the lemonade into an ice mold and placed it in the freezer for 4 hours.
3. She took the lemonade ice cube and placed it out into the sunlight until it disappeared.
1. liquid
2. solid
3. gas