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Ch1
Ch2
Ch3
Ch4
Ch5
100
Freezing 
Which of these is a physical change? 
100
Rubber

What is considered an Amorphous solid?

100
the atomic number of element is determined by the number of 
protons
100
valence electrons
An electron dot diagram shows an atom's number of?
100
Which of the following results in a chemical change in matter? 

A: bending a straw

B: Boiling water

C: Braiding hair

D: Burning wood 

D. Burning Wood
200
Evaporation or distillation 
How could you prove that dissolving table salt in water is a physical change?
200
Liquid 
When you see fog or clouds, you're seeing water in the ____ state. 
200
two isotopes of an element have the same number of the proton but different numbers
neutrons
200
ion
When an atom loses or gains an electron, it becomes a(n)?
200
How can you balance a chemical equation?
Change the coefficients
300
Rusting 
Which of the following is a chemical property?
300
Freezing
Which of the following changes of state is exothermic?
300
the rows in a periodic table are called 
periods 
300
non-polar bond 
A covalent bond in which electrons are shared equally is called a?
300
How does the energy of the products compare with the energy of the reactants?
Because all of the energy from the reactants are combined to make the product's energy. 
400
Kilogram 
What is the SI unit of mass?
400
Liquid water
The sample has a definite volume but no definite shape, which state of matter is it? 
400
unlike metals, solid nonmetals are 
dull and brittle 
400
metallic bonds
The metal atoms in iron are held together by?
400
Which of the following would increase the rate of reaction?

A: maintain a constant temperature 

B: increase the concentration of the reactants

C: increase the activation energy

D: add an inhibitor 

B: increase the concentration of the reactants
500
Can be observed without changing 
A substance can be classified by its physical properties, which are properties that 
500
The particles are closely locked in position. 
What describes a solid?
500
two elements that have properties similar to those of chlorine are 
bromine, and fluorine
500
3
How many sodium ions are needed to balance the change of one phosphate ion?
500

Which of the following is the best evidence for a chemical reaction? 
A: change in temperature

B: change of state

C: formation of a new substance

D: gas bubbles

A: change in temperature