funamentals Flashcards
sulfuric acid formula and salt ending
H₂SO₄, sulfate
hydrochloric acid formula and salt ending
HCl, chloride
ethanoic acid formula and salt ending
CH₃COOH, ethanoate
nitric acid formula and salt ending
HNO₃ nitrate
acid definition
a substance that releases H+ ions in water (pH<7)
base definition
a substance that reacts with an acid to form a salt
bases examples
cc
alkali definition
a soluble base (pH>7)
indicator definition
a chemical that changes colour depending on whether its an acid or alkali
general equation for metal oxide + acid
metal oxide + acid -> salt + water
when reacting a metal oxide with an acid why will it not produce an alkali solution
when reacting a metal oxide with an acid it will not produce an alkali solution due to the excess metal oxide not reacting
general equation : metal + acid -> salt + hydrogen (MASH)
test for hydrogen
lit splint burns with a squeaky pop
general equation: metal carbonate + acid ->
general equation: metal carbonate + acid -> salt + water + carbon dioxide
test for carbon dioxide
limewater turns cloudy
general equation: metal hydroxide + acid ->
general equation: metal hydroxide + acid -> salt + water
colour and strength, pH1-2, 3-4, 5-6, 7, 8-10, 11-14
1-2 strong ,red, 3-4 weak, orange, 5-6 acid, yellow, 7 neutral ,green, 8-10 weak alkali, blue,11-14 strong alkali, purple
what is the pH scale a measure of
the pH scale is a measure of how acidic a substance is. Strong acids react more vigorously than weak acids
what is universal indicator
universal indicator is a mixture of many different indicators, the mixture gives universal indicator a wide range of colours most indicators have 2 or 3 diff colours but do not all change at exactly pH7. this means they will have 1 colour below a specific pH and a diff colour above that pH
solid to gas =
sublimation
solid to liquid = melting
liquid to solid =
freezing
liquid to gas
evaporating
gas to liquid =
condensation
gas to solid =
deposition
melting and boiling both require energy how much depends on…
the strength of the forces between the particles
the stronger the forces…
the more energy and therefore a higher melting point
limitations on diagram:
no forces shown between particles, particles show as inelastic spheres
state symbols: solid, liquid, gas, aqueos solution
s,l,g,aq all lowercase
atom definition
smallest part of an element that can exist
molecule definition
2 or more atoms chemically bonded together
compound definition
2 or more diff elements chemically bonded together
element definition
a substance that contains only one type of atom
carbon dioxide -CO2
nitrogen N
ammonia NH3
chlorine Cl2
CO carbon monoxide
CH4 methane
NaCl sodium chloride`
C6H1206 glucouse
sulfur dioxide S02
sulfur dioxide S02
Before electrons were discovered the pre thompson model was that an atom is an invisible sphere
Before electrons were discovered the pre thompson model was that an atom is an invisible sphere
the discovery of an electron led to Thompson’s plum pudding model of an atom
a sphere of positive charge with randomly moving negatively charged electrons
rutherford and marsden alpha scattery experiment expectations and reality
positive alpha particles fired at gold atoms should be deflected evenly by positive spheres however most α particles went through showing that most of the atom is empty space, some particles were deflected at extreme angles showing that the centre was positively charged and has a mass
the nuclear model was developed:
positive nucleus with a mass, cloud of randomly moving negative electrons
the bohr model showed electrons orbiting the nucleus in electron shells
positive protons, neutral neutrons, negative electrons
why does the centre of the nucleus have an overall positive charge
it contains positive protons and neutral neutrons
why does the centre of the nucleus have an overall positive charge
it contains positive protons and neutral neutrons
atoms have a radius of 0.1nm and a nucleus has a radius of 1/10,000th the size of an atom
the actual mass and charge of subatomic particles are so small that relative mass and charge are used
go to chem book for table
numbers of proton = atomic number
number of electrons = number of protons
the overall charge on an atom is neutral because there is the same number of positive protons as negative electrons
number of neutrons = mass number - atomic number
relative mass definition
the average atomic mass of all isotopes present in percentage
relative mass definition
the average atomic mass of all isotopes present in percentage
absolute mass definition
sum of numbers of protons and neutrons mass
electrons orbit the nucleus in shells
each shell is fully filled before moving on to the next the rule is called 2.8.8.18 rule
isotope definition
an atom of an element that has the same number or protons but a diff number of neutrons
