Units A-C Flashcards
What is the formula to change a measured value into a required unit?
Measured Unit Multiplied by Conversion factor(s) = Required unit.
What is a conversion factor?
A fractional expression relating or connecting two different units.
Another way of writing the conversion formula?
Unknown amount = Initial amount X Conversion Factor.
What is Proper Scientific Notation?
a x 10^b
To convert from Scientific Notation to a number how should you move the decimal?
Move the decimal to the Right for Positive powers and to the Left for Negative powers.
Are Negative Powers of 10 converted into positive powers?
No, Never.
What is the first Exponent rule?
When multiplying with the same base, add powers.
What is the second Exponent rule?
When dividing with the same base, subtract powers.
What is matter?
Anything that has mass and takes up space.
What are the characteristics of a solid?
Fixed shape and volume
Particles touch
Particles don’t move
What are the characteristics of a liquid?
Fixed volume
No fixed shape, molds to container
Particles are touching and move fluidly
What are the characteristics of a gas?
No fixed shape OR volume
Fills container
Particles are apart and move freely (seldom touch)
What is physical change?
A reaction where the chemical composition of a substance is unchanged (ie ice melting)
What is a chemical change?
A reaction where the chemical composition changes and bonds between atoms break and form. These create new substances.
What is a pure substance?
A substance that can’t be separated into other materials by any physical means.
What is a mixture?
Two or more substances that can be separated by physical processes. These can be Homogeneous or Heterogeneous.
How are substances distributed in a Homogeneous mixture?
Evenly, like sugar and water.
How are substances distributed in a Heterogeneous mixture?
Unevenly, like oil and water.
What does amu stand for?
Atomic mass unit
Properties of electrons?
Symbol e-, charge -1, location outside nucleus
Properties of protons?
Symbol p, Charge +1, Location inside nucleus
Properties of neutrons?
Symbol n, charge 0, location inside nucleus
What does immiscible mean?
Insoluble
What does miscible mean?
Mutually soluble liquids in all proportions
A neutral atom has the same number of what?
Protons and neutrons
An ion has a different number of what?
Electrons and neutrons.
What is an ion and how do you tell what kind it is?
An ion is an atom with a charge (different number of electrons and neutrons). If there are more electrons it is negative, more protons and it’s positive .
What is another name for a positive ion?
A Cation (think CAT-ion)
What is another name for a negative ion?
An anion (think onion)
What is density?
The relationship between the mass and volume of an object.
What is the formula for density?
Density = mass / volume
What is an Isotope?
Two atoms that have the same number of protons but different number of neutrons (different mass)
Who was the first person to suggest the idea of the atom?
Democritus
Which atomic particle did J.J Thompson discover?
The electron.
How did Rutherford’s experiment help him discover the nucleus
Most of the alpha particles went through the gold sheet, some bounced back at large angles, suggesting a mass.
Who discovered the Chocolate chip/ plum pudding model of the atom?
J.J. Thompson
What causes fireworks?
Electrons shifting between energy levels
1L is how many mL?
1000mL
1cm cubed is how many mL?
1mL
1kg is how many g?
1000g
1g is how many mg?
1000mg
1m cubed is how many L?
10^3 L
1t (Tonne) is how many kg?
10^3 kg
