Everyday Science Quiz

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Date:

Instructions: Why does bread rise, why is the sky blue, and what makes ice float? Test the science behind daily life.

1.
Why does bread rise when you bake it?
A
Yeast produces carbon dioxide gas bubbles that get trapped in the dough
B
The flour absorbs water and swells up
C
Baking soda melts and creates steam
D
Heat causes the gluten to stretch and pull the bread upward
2.
Why is the sky blue on a clear day?
A
The ocean reflects blue light upward into the atmosphere
B
Sunlight bounces off blue-colored air molecules
C
The atmosphere scatters blue light more than other colors of sunlight
D
Oxygen gas is naturally blue when spread out thinly
3.
Why does ice float on water instead of sinking?
A
Ice is colder than water, and cold things always rise
B
Ice contains trapped air bubbles that make it buoyant
C
Frozen water expands and becomes less dense than liquid water
D
Salt in tap water pushes ice to the surface
4.
What makes a cut apple turn brown after you slice it?
A
The apple is reacting with the nitrogen in the air
B
Enzymes in the apple react with oxygen in the air
C
Sugar in the apple caramelizes when exposed to light
D
Bacteria from the knife immediately begin to digest the apple
5.
Why does a woolen sweater make crackling sounds and sparks when you pull it off in the dark?
A
Wool fibers contain tiny amounts of flammable lanolin oil
B
Static electricity builds up as the sweater rubs against your hair and skin
C
The wool contracts rapidly in cool air and releases energy as light
D
Tiny metal particles woven into wool cause electrical sparks
6.
Why does a mirror show your face reversed left-to-right but not upside down?
A
Mirrors only reflect horizontal light waves
B
The silver coating on the back of a mirror selectively blocks vertical reflection
C
A mirror actually reverses front-to-back, not left-to-right — your brain interprets this as a left-right flip
D
Your eyes are positioned side by side, causing them to flip horizontal images only
7.
Why does rubbing your hands together make them feel warm?
A
Skin cells release stored chemical energy when compressed
B
Friction converts the energy of motion into heat energy
C
Blood rushes to the surface of the skin more quickly when rubbed
D
The moisture between your palms heats up from the pressure
8.
What causes the familiar smell just before or during a rainstorm?
A
Ozone produced by lightning high in the clouds drifting down
B
A chemical called geosmin released by soil bacteria, mixed with rain hitting dry ground
C
Water vapor reacting with dust particles in the air
D
Pollen grains bursting open when they absorb moisture
9.
Why does a boiled egg become hard, while a raw egg is runny?
A
Heat drives off the water inside the egg
B
Heat causes the egg proteins to unfold and bond together permanently
C
The egg shell absorbs heat and transfers it as pressure to solidify the interior
D
Boiling converts liquid fat in the yolk into solid fat
10.
Why does a wooden door sometimes stick and become hard to open in humid summer weather?
A
Heat causes the metal hinges to expand and press the door into the frame
B
Wood absorbs moisture from the air and swells slightly
C
The paint on the door softens in heat and acts like glue
D
High humidity makes the air denser, creating extra pressure against the door
11.
What actually happens inside a microwave oven to heat your food?
A
Infrared rays from a hidden heating coil warm food from the outside in
B
Radio waves excite water molecules in food, causing them to vibrate rapidly and generate heat
C
A concentrated beam of light focuses on the center of the food and radiates outward
D
Electrical currents pass through the metal turntable and heat the food by conduction
12.
Why does a drinking straw work? What force actually pulls the liquid up?
A
Suction — your lungs create a pulling force that drags liquid upward
B
Atmospheric air pressure pushes the liquid up once you remove the air inside the straw
C
Capillary action draws liquid up through the narrow tube
D
Gravity is reversed inside a sealed straw, causing liquid to rise
13.
Why does a loaf of bread go stale after a few days?
A
Mold spores immediately begin breaking down the bread's structure
B
The bread dries out completely as all moisture evaporates
C
Starch molecules in the bread recrystallize and become firm over time
D
Yeast in the bread continues to ferment and hardens the loaf
14.
Why do your eyes take a little while to adjust when you walk into a dark room?
A
Your pupils need time to physically widen to their full size
B
The retina switches from cone cells to rod cells, and the rod cells need time to build up light-sensitive pigment
C
The brain gradually increases the sensitivity of the optic nerve signal
D
Tears spread across the eye surface to improve low-light focusing
15.
Why does a can of soda fizz and overflow when you open it after it has been shaken?
A
Shaking warms the liquid and hot liquid holds less dissolved gas
B
Shaking creates tiny bubbles that merge into one large burst when the seal is broken
C
Shaking causes the carbon dioxide to chemically react with the sugar and produce extra gas
D
Shaking coats the inside walls with liquid, blocking the carbon dioxide from escaping slowly

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