Chemistry-flashcards whole year
physical changes–>
*Create no new substances.
*Are usually easy to reverse.
*Absorb or release small amounts of energy
Chemical changes–>
*Create new substances.
*Are usually difficult to reverse.
*Absorb or release large amounts of energy.
Test for water
*Anhydrous copper (II) sulphate: turns from white to blue
This tells you that water is present, but not how pure it is.
Two physical tests for water:
*Melting point (MP) = 0 oC
*Boiling point (BP) = 100 oC
Purer water matches these properties more closely
Definition of an element
one type of atom
Definition of a compound
A compound is a substance containing more than one type of atom, chemical bonded together
Definition of a mixture
two or more substances that are mixed together but not chemically combined
How can compounds be formed
Compounds can often be formed by heating their elements together. e.g. For example: if you heat the elements zinc and sulphur, they form the compound zinc sulphide
Solute
The substance which is going to be dissolved
solvent
The liquid which is going to do the dissolving
solution
The resulting mixture of solute dissolved in solvent
soluble
A substance which can be dissolved
saturated
A solution in which no more solute can be dissolved
insoluble
A substance which cannot be dissolved
suspension
A solid floating in a liquid because it cannot dissolve
Salt = ?
Water =?
Saltwater = ?
*Salt = solute, it’s going to be dissolved
*Water = solvent, it’s going to do the dissolving
*Saltwater = solution, formed because some of the salt dissolves in the water
what do we measure solubility in
We measure solubility in g per 100 g of solvent.
solubility lines on graph=
on the line =?
under the line=?
above the line=?
on the line= saturated
under the line= soluble
above the line= insoluble
what is the relative mass of a proton
1.000
what is the relative mass of a neutron
1.000
what is the relative mass of an electron
0.0005
now bozo whats the relative charge of a proton bet you dont know this one
+1 IF YOU DONT PUT THE SIGN INFRONT YOU WILL WAKE UP IN THE BACKROOMS XOXO
whats the relative charge of a neutron
0 CUZ ITS NEUTRAL?!
what’s the relative charge of a electron
-1 DONT FORGET THE SIGN DUMMY
What are in the nucleus
protons and neutrons!
what are in the shells (energy levels)
ELECTRONS #ALONE#DEPRESSED
WHAT IS THE ATOMIC NUMBER
THE NUMBER OF PROTON
WHAT IS THE MASS NUMBER
THE TOTAL NUMBER OF NEUTRONS ANDDDD PROTONS
28
Si
14
How many neutrons?
14 (the bottom number is the number of protons and protons only) aka the atomic number
28
Si
14
How many neutrons?
14 since the mass number is protons AND neutrons so the mass number minus the atomic number will give us 14 ITS SO SIMPLE BRO
Number of electrons=?
number of electrons= number of protons
what are isotopes (istg if you dont include them two things your fish is gonna drown you)
isotopes are ATOMS that have the SAME NUMBER OF PROTONS BUT DIFFERENT NUMBER OF NEUTRONS
isotopes: Mass number Abundance
chlorine-35¦ 35 ¦ 75%
chlorine-37¦ 37 ¦ 25%
RAM= (75%x35) + (25%x37)
—————————— = 35.5
100
What is RAM
Relative atomic mass is the average mass of an atom of an element, taking into account the different masses of each isotope
