We love science
Atoms are the smallest unit of an ________
Molecules are the smallest unit of an _______
Element
Compound
What is a covalent bond?
when atoms share electrons
What is Miss. Abdo's 3 favorite pies?
Buttermilk
Pumpkin
Lemon
What is an ionic bond?
When atoms give and take electrons.
which bond is between 2 nonmetals?
covalent
which bond is between a metal and a nonmetal?
Ionic bond
What is the difference between the atomic number and the atomic mass?
Atomic number is where it is on the periodic table and refers to the number of protons but the atomic mass is the protons plus the neutrons.
What is the region called where electrons are located?
Electron cloud
______a substance that cannot be broken down into simpler substances by chemical means. Each _____ is made of one kind of atom.
Element
Chemistry studies four things what are they?
Chemistry is the study of matter, its properties, changes, and classification
_____is a substance made up of 2 or more different atoms bonded together
compound
True or False:
When elements combine to make a compound, they always do it in exact proportions.
True
The chemical formula has a coefficient and a subscript. What does the coefficient tell us? what does the subscript tell us?
Coefficient= number of molecules
Subscript= number of atoms
________is matter that has a fixed composition and definite properties.
________is a combination of substances that are not chemically combined
Pure substance
Mixture
______substances in the mixture are NOT evenly distributed.
_______substances in the mixture ARE evenly distributed
Heterogeneous mixture
Homogeneous mixture
What is the difference between physical and chemical properties?
Physical properties don't change the identity of a substance but chemical properties do.
How do we observe physical properties?
5 senses
What are the 7 diatomic molecules
O2, N2, Cl2, F2, H2, Br2, I2
True or False:
A physical property of a substance can be observed WITHOUT changing the substance.
True
Things that float are more or less dense?
less dense
Solid ----- liquid is _____
Liquid ----- gas is ______
Solid ------ gas is _______
Liquid ----- solid is _______
Gas ------- liquid is _______
Gas ------- solid is ________
Solid ----- liquid is melting
Liquid ----- gas is evaporation
Solid ------ gas is sublimation
Liquid ----- solid is freezing
Gas ------- liquid is condensation
Gas ------- solid is deposition
What are the 3 equations for density?
What are the units for density?
What are the units for volume?
What are the units for mass?
d=m/v
v=m/d
m=d x v
g/cm3, cm3, g
What is flammability?
What is reactivity?
Give me an example of each.
Flammability= the ability to burn
Reactivity=the capacity of a substance to combine with another substance to make new substance(s)
Flammability= skin, hair
Reactivity= rust...
Give me 5 examples for separating out mixtures?
•Mechanical means (picking and sorting)
•Sifting
•Filtration
•Evaporation
•Magnetism
•Centrifugation
•Distillation
•Fractional recrystallization
What is conservation of matter?
No matter how you break things down or what kind of reaction you create, there is always the same amount of matter before and after the reaction.