Chemical Reactions Test

What is the Law of Conservation of Matter?

Atoms can neither be created nor destroyed

3 requirements of chemical reactions

Correct alignment, collision, and sufficient energy

Toast burning (chemical?)

Yes

Chopping firewood (chemical?)

No

Mixing red and blue to make purple (chemical?)

Yes

Blowing bubbles in milk (chemical?)

No

Ice cubes cooling hot chocolate (chemical?)

No

Smell given off from a stink bomb (chemical?)

Yes

Fe+S=FeS

Synthesis

2HgO=Hg2+02

Decomposition

Zn+CuSO4=ZnSO4+Cu

Single replacement

KCl+AgNO3=KNO3+AgCl

Double replacement

Fuel+O2=CO2+H2O

Combustion

Endothermic reaction

Requires heat, surroundings become cool

Exothermic reaction

Gives off heat, surroundings become warm

What are the 5 indicators of chemical reactions?

Smell, color, gas, temp, and new substance

What CAN be changed in a chemical reaction?

Coefficients- tell you the number of molecules in a reaction

What CANNOT be changed in a chemical reaction?

Subscripts- tell you the number of atoms in an element

What are the 4 things that can affect the rate of a collision?

Increased temperature, concentration, surface area, and a catalyst

What does using catalyst do to a reaction?

It lowers the activation energy

What is concentration?

An increased amount of reactions

What is collision theory?

When particles collide with sufficient energy with the correct alignment