Chemistry -remison Flashcards
(35 cards)
What are Reactants and Products in a Chemical reaction?
A reactant is one of the starting materials that undergoes a chemical change to form products during the reaction. Products are the new materials or compounds formed as a result of the reaction between reactants.
What is the Law of Conservation of Mass
matter cannot be created or destroyed in a chemical reaction
what are the 3 states of chemical substances
elements (one type of an atom), compounds (multiples variants of atom chemically bonded), mixtures (compounds or elements mixed together non chemically).
what are 6 indicators a chemical reaction has occurred?
- temp change
- gas release
- colour change
- precipitate in substance (solid forming)
- energy release (light and heat/explosion)
- original substance disappears
what is an isotope
An isotope is a variant of an element that has the same number of protons but a different number of neutrons in its atomic nucleus. This results in a different atomic mass for the isotope. Isotopes of the same element have similar chemical properties but may have distinct physical properties and varying levels of stability.
what are the 3 isotopes of hydrogen
protium/hydrogen (1H), deuterium (2H), tritium (3H)
How do you find the protons, neutrons and electrons in an atom
protons=atomic number
neutrons=atomic weight-atomic number
electrons=atomic number
what are the 7 groups of elements
alkali metals, alkaline earth metals, transition metals, halogens, noble gases, rare earth metals, actinides
what is a valence shell?
a valence shell is the outer ring of electrons in an atom, it also defines an atoms reactivity and tendency to form chemical bonds. a atom with more atoms in its valence shell is often more stable than one with less. atoms always want a full outer shell and will try get rid of electrons or add them to do this
what is an ion?
an ion is an atom that has a different amount if electrons than it’s regular self. if an ion gains an electron it becomes negatively charged (anion), if the ion loses an electron it becomes positively charged (cation)
how many electrons can fit in the first and second valence shell?
the first valence shell has a capacity of 2 electrons and the second, third, fourth, fifth, and so on shells will always have a capacity of 8 electrons.
what is ionic bonding
ionic bonds usually form with a metal and non metal. the metal donates one or more electrons to the non metal which makes an anion and a cation. these types of bonds are formed because of the attraction between the positive and negative charge. the name of these compounds always starts with the metal and ends with the non metal
what is the configuration of ionic compounds
ionic bonds form in a crystal lattice or hexagon lattice and are held together by electrostatic force which is stronger than a covalent bond.
what happens when you make sodium chloride
the sodium atom gives its electron to the chlorine atom and forms an ionic bond, the sodium atom becomes the cation and the chlorine atom become the anion
how to name ionic compounds
the positive ion always comes first and the negative ion comes second. the positive ion gets the element named and the negative usually has the work ‘ide’.
what is a covalent bond
a covalent bond is when two or more non metal atoms react together, atoms share electrons in this bond. covalent bonds often dissolve in water but don’t disassociate into their ions. for example sugar will dissolve in water but its still sugar. examples include [O2]-2, NH3.
what is a polyatomic ion?
A polyatomic ion is a group of 2 or more atoms bonded by covalent bonds with an unbalanced charge. examples include [NH4]+1, [OH]-1
metal+acid=
K+2HCl=
salt+hydrogen
KCl+H2
(metal and acid reaction)
acid+metal carbonate=
H2SO4+FeCO3=
salt+carbon dioxide+water
FeSO4+H20+CO2
(acid+metal carbonate)
acid+base=
2HNO3+MgO=
salt+water
Mg(NO3)2+H2O
(neutralisation reaction)
A neutralisation reaction is when an acid reacts with a base to produce salt and water. (acid is neutralised)
what are the 3 types of neutralisation reactions
acid+hydroxides, acid+oxides, acid+carbonates
what is a combustion reaction
CH4+2O2=CO2+2H2O
A combustion reaction is simply burning a substance in oxygen.
a complete combustion with hydrocarbons releases water and co2. an incomplete version will release carbon monoxide and water or carbon and water. the products of combustion have various effects
what is corrosion reaction
When a metal reacts with oxygen it forms a metal oxide and the process may be referred to as corrosion. This is because the metal oxide ‘eats away’ or corrodes the metallic element.
4Fe+3O2=2Fe2O3
what is a precipitation reaction
In a precipitation reaction two clear solutions mix to form an insoluble solid known as a precipitate.
AgNO3+NaCl=AgCl+AgNO3
