water concentrations, acids and bases Flashcards
what is the measured Molarity ratio?
solute:solvent
what is the equation to find the weight of a molecule?
N(number of moles)= mass(grams)/molecular weight (Da)
Is a dative bond reversible?
Yes
What would you call a concentration with high H+ (hydrogen ions)
Acidic
What would you call a solution with high OH- (Hydroxide ions)
Basic
What would you call a solution with equal H+ and OH- ions?
Neutral
What is the formula to find pH?
pH= - log(H+)
E.g. -log 10 (10-7) = -(-7)=7pH
Which way on the pH scale is more acidic?
A more acidic solution has a pH of 0-6.9
What is the pH scale of an alkaline (basic) solutions?
7.1 - 14
Is pH3 3 times more acidic than pH6 or 1000x? Why?
1000x because of the logarithmic scale (10x10x10)
What is a buffer?
A substance that minimizes changes in the concentrations of H+ and OH- by accepting and releasing hyrodogen ion when hydroxide ions are in excess or depletion.
What is the base equivalent of carbonic acid? H2CO3
Bicarbonate and a hydrogen ion
HCO3 + H+
What is Avogadros number?
6.022 x 10(23)
What is 6.022x 10(23) called?
Avogadros number
What is Molarity?
A concentration of moles in a solution
What is the formula for Molarity?
Concentration= number of moles/litres of solution
M= mol/L
what is the molecular weight of glucose?
C6H12O6
Carbon=12
hydrogen=1
oxygen=16
(6x12)+(12x1)+(6x16)
=72+12+96
=180g/mol
what is the molecular weight of sodium chloride?
NaCl
Sodium=23
Chlorine=35.5
(1x23)+(1x35.5)
=58.5 g/mol
what defines a strong base or acid?
when the compounds dissociate completely in water and cannot be reversed
example of a strong base
sodium hydroxide
example of a strong acid
hydrochloric acid
example of a weak base
ammonia
what defines a weak base or acid?
when they are able to accept back or release hydrogen ions, so reverse the dissociation
