Which of the following is a physical property?
1- NaCl dissolves in water
2- NaCl does not react with O2 (g)
1- NaCl dissolves in water
In the following reaction, if 4.00g of H2 reacts completely with 64.00 of O2, how much water is produced?

68.00 g water produced
(conservation of matter/mass)
How do you separate solids of different sizes?
Sifting/use mesh
Which of the following is the average kinetic energy?
1. Heat 2. Temperature 3. Kinetic Energy
2. Temperature
The temperature of a water sample changes from 10.°C to 20.°C when the water absorbs 420 Joules of heat. What is the mass of the sample?
420J= m(4.18 J/g°C)(20°C -10°C)
m= 10 g
Explain the difference in terms of particle distribution of a homogeneous and a heterogeneous mixture.
Homogeneous- uniform distribution of particles
Heterogeneous- non-uniform/variable distribution of particles
Which of the following is/are homogenous mixture(s)?
1. Soil 2. NaCl(aq) 3. Cu
2 - NaCl(aq)- the "aq" tells you it is NaCl AND water
How do you separate liquids with different boiling points?
Distillation
The act of hearing a car door slam involves which type of energy: kinetic or potential
Kinetic energy
A sample of 50.0g of copper changes from 75°C to 50°C. Is this an exothermic or endothermic change? Will the heat be positive or negative?
Exothermic, with a -q
Why? Temperature change is 50°C-75°C = -25°C
Identify the following as being able to be broken down chemically or not.
1. S8
2. H2S
1. S8 - can't be broken down chemically (element)
2. H2S- can be broken down chemically (compound)
Which of the following is/are heterogenous mixture(s)?
1. Air 2. A metal alloy 3. granite
3- granite, you can see the ribbons of different colors
Which is a diagram of two elements?

2- two diatomic elements
Object A has a temperature of 30 degrees C while object B has a temperature of 40 degrees. Describe the heat transfer when the two objects meet.
Heat flows from B to A
Sort the list of chlorine's properties by whether they are physical or chemical properties:
1. Reacts explosively with H in presence of light.
2. Soluble in organic solvents
3. When dissolved in water, will form HCl.
4. A greenish/yellowish gas
Physical: 2,4
Chemical: 1,3
A given substance contains two different elements in the same ratio in every sample. The given substance must be a....
Compound
Two students each have a sample of matter with the same components but with a different percent composition. What is the matter?
A mixture
What does this particle diagram represent? 
a solid mixture-
What is 65.00 OC in Kelvin?
338.15K
Explain the difference between exothermic and endothermic in terms of heat flow. Which one feels warm to the touch? Which one feels cool?
Exothermic- heat flows out and feels warm
Endothermic- heat flows in and feels coo.
Which of the following is a pure substance?
1. CO 2. Co
They both are! One compound and one element!
Explain in terms of composition, what is the same between a compound and a mixt\ure?
What is different?
Same - Both are composed of two or more substances
Different- Compounds have fixed composition
Mixtures have a variable composition
What is the name for the technique that separates components of a mixture based on their intermolecular attractions?
Chromatograhy
Which has the higher average kinetic energy:
1. 10g of water at 25 OC
2. 100g of water at 25 OC
They have the same average kinetic energy
Top
Bottom
What do these two particle diagrams represent?
Top: mixture of elements
Bottom: mixture of two elements and a compound