Chemical changes
give an example of a chemical change
rust, vinegar and baking soda etc
Give an example of a physical change
cutting, melting, splitting, etc
True or false: when you mix baking soda and vinegar matter is destroyed causing the bubbling
false
does forming chemical bonds store or release energy?
forming bonds stores energy,
give an example of how cooking is just chemical changes
browning anything on the stove
make a physical change
folding clothes.
break a pencil
rip a paper
what is the smallest number of elements you need to make a mixture
2
give 3 signs that a chemical change happened
released bubbles
changed color
precipitate
gave off heat light, etc
cutting paper into strips
lighting paper on fire
putting paper in the freezer
lighting on fire = chemical
define a pure substance
every particle making up a substance is the same
Define "chemistry"
the study of matter and how it changes
explain why salt dissolving in water is NOT a chemical change
not making new chemicals, can just evap water and separate them
can be observed about a substance without creating a new substance
draw the particles in a mixture and a pure substance
all same type of molecule vs multiple different molecules
how many atoms are in the chemical formula: (also what is it?)
C6H12O6
24 atoms total, its glucose
Draw the particles in the 3 phases of matter
solid, liquid, and gas
write a chemical formula showing the process of rusting
iron + oxygen -> rust (iron oxide)
explain how sublimation is a physical change
Not making any new chemicals. If you get the CO2 gas super cold again it will form back into a solid block
Give an example of a homogeneous mixture and a heterogeneous mixture
salt water = homogeneous
salad dressing = heterogeneous
what 3 particles make up an atom?
protons neutrons and electrons
Draw and label a temperature vs time graph showing water changing from a gas into a liquid into a solid. (label your graph)
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