Classification of Matter
What are the two main types of pure substances?
Elements and compounds
What are two types of energy?
KE, PE, TE, NE, etc.
What are the three common states of matter?
solid, liquid, gas
Is melting ice a physical or chemical change?
physical
Celsius and kelvins
What is the difference between homogenous and heterogeneous mixture?
homogeneous: uniform throughout
heterogeneous: visibly different parts
What is the study of energy movement and transformation called?
Thermodynamics
What causes a phase change in matter?
Adding or removing thermal energy
Which is a chemical property: flammability or density?
flammability
Why is the Kelvin used in Chemistry?
it is an absolute scale based on molecular motion
Is toxicity a physical or chemical property?
Chemical
What is thermal energy?
sum of the kinetic energy of particles in a substance
What does the kinetic-molecular theory say about matter?
Is rusting of a bicycle physical or chemical?
chemical
barely moving at all; actually if possible they would have zero motion
What is the fundamental particle of elements?
atom
What happens in an exothermic process?
energy is released
What is the process of a gas turning directly into a solid?
Deposition
A wafer of silicon being cut into chips is physical or chemical?
physical
What happens to a substance when thermal energy is added to it?
the particles move faster and spread out, the kinetic energy in the particles increases
Physical: observed without changing composition
Chemical: describe how matter reacts or changes composition
What is the second law of thermodynamics?
Energy naturally flows from high to low concentration; entropy in isolated system always increases
What is the process of a gas turning into liquid?
Condensation
Identify a process involving both physical and chemical.
dynamite exploding and building collapse
What are the fixed points for Kelvins?
373.15 K and 273.15 K