unit one - 1.1 (fundamental ideas in chemistry) and 1.2 (limestone and building materials) Flashcards
relative charge of a proton
+1
relative charge of a neutron
0
relative charge of an electron
-1
overall electric charge of atom
neutral
number of electrons is equal to
number of protons
particular elements have the same number of
protons
atomic number
number of protons
mass number
sum of protons and neutrons
elements in the same group will have
same number of electrons in their highest energy level
group 0
noble gases
why are noble gases unreactive
full highest energy level (8)
how many electrons does helium (noble gas) have in it’s highest energy level
2
how do atoms join together to form compounds
give, share or take to form ions/molecules
compounds of non-metals and metals form
ions
compounds of non-metals form
molecules (held together by covalent bonds)
metals …… electrons
lose
non-metals ….. electrons
gain
why does the mass of products equal the mass of the reactants?
atoms cannot be lost or made
limestone is needed for
buildings, positive benefits of using this material outweigh negatives of quarrying
limestone is composed of
calcium carbonate (CaCO3)
how can calcium carbonate be decomposed
thermal decomposition (heating) which makes calcium oxide and carbon dioxide
what does calcium oxide react with to make calcium hydroxide
water
limewater is used as a test for what? what is the effect?
carbon dioxide, limewater goes cloudy
limestone is heated with …. to make …..
heated with clay to make cement
