20 questions-chemical changes Flashcards
where in the reactivity series will you find copper
the bottom
which 2 nonmetals are found in the reactivity series
hydrogen and carbon
write a word for oxidation if magnesium to form magnesium oxide
magnesium + oxygen -> magnesium oxide
calcium is in group 2 of the periodic table ,what charge will be on a calcium ion
+2 since it loses 2 electrons
what ion is produced by acids
H+ (hydrogen ions)
whats the ph of a neutral solution
7
true of false,alkalis have a ph of more than 7
true
when an acid reacts with a metal which gas is produced
hydrogen
which acid has the formula h2s04
sulfuric acid
what ion is produced by all alkalis
OH-
whats a strong acid
an acid thats fully ionised in water
the ph of solution changes from 6 to 4 what happens to the concentration of hydrogen ions
decreases by 10
define oxidation in terms of electrons
the loss of electrons
define reduction in terms of electrons
the gain of electrons
Ca → Ca2+ + 2e-
2H+ + 2e- → H2, which is oxidised
calcium since it looses electrons in the reaction
Ca → Ca2+ + 2e-
2H+ + 2e- → H2 which is reduced
hydrogen since it gains electrons
whats the general ionic equation for neutralisation
H+ OH- -> H20
what do we call the molten ionic compound used in electrolysis
electrolyte
whatre the products of the electrolysis of the aqueous solution of sodium bromide
hydrogen and bromine
whatre the half equations for reactions that takke place at each electrode in the electrolysis of aq sodium bromide
At the cathode: 2H+ + 2e- → H2
At the anode: 2Br- → Br2
