yearly year 10 chemical cauldron Flashcards
what is the law of conservation of mass
Mass in an isolated system is neither created nor destroyed
how does the law of conservation of mass relate to chemical reactions
during a chemical reaction things get bigger and smaller but mass is never destroyed or created.
what are reactants
they are substances that are used in a chemical reaction
what are products
products are the end result of a chemical reaction
what is valency
a measure of its combining power with other atoms when it forms chemical compounds or molecules.
what is an ionic bond
the metal loses electrons to become a positively charged cation, whereas the nonmetal accepts those electrons to become a negatively charged anion.
what is a covalent bond
haring of electron pairs between atoms two have full valency shells
what is a metallic bond
force that holds atoms together in a metallic substance.
give an example of ionic bonds
NACL
NA loses one electron whereas CL gains an electron
what is an example of covalent bonding
H20 share electrons to become stable
what is an example of a metallic bond (4)
Cu, Al, Au, Ag
what is precipitation
is the emergence of a insoluble solid in a liquid
what is the importance of the activity series
By using the reactivity series of metals, one can predict the products of displacement reaction.
give an example of the effect of the activity series of metals
magnesium metal can displace zinc ions in a solution.
what is the metal displacement reaction
Displacement reaction is a chemical reaction in which a more reactive element displaces a less reactive element from its compound.
give an example of the displacement reaction
Reaction of iron nails with copper sulphate solution
what is a combustion reaction
an burning reaction in which something reacts with oxygen.
what is neutralisation
a type of chemical reaction in which a strong acid and strong base react with each other to form water and salt.
give an example of neutralisation
HCl + NaOH ->NaCl + H20
Properties of Acids (4)
turn blue litmus red
taste sour
acids corrode metals
Positively charged hyrdogen ions (H+)
properties of Bases
turn red litmus blue taste bitter negatively charged hydroxide ions ( OH-) feel slippery strong bases are caustic
what happens when metals react to acids
Acids react with most metals to form a salt and hydrogen gas
what happens in a reaction between acids and carbonates
salt, water and carbon dioxide gas are formed.
