p. 74 – 173 quantitative chemistry = analytical chemistry, assigning numbers
(quantifying) to a substance o the number of particles, measuring the mass, determining concentration, etc. o we have already done some analytical chemistry in this course (chromatography, % yield, % by mass, etc.)
 this unit focuses on assigning numeric values to substances like elements & compounds
 the “mole” is a quantitative measurement, just like a dozen o just like the term “organic”, the term “mole” means something entirely different to a chemist
 the mole is a measurement of quantity (the # of particles of a substance), not an animal

all matter is made of particles

analytical chemistry deals with determining how many particles (i.e. atoms of elements) are in a substance, how concentrated they are, how they interact with other particles o crucial for pharmaceutical industry o also useful in forensics, food science, agriculture, testing for environmental pollution

pharmacists must understand the chemical interactions of drugs o knowing what dosage to prescribe a person can mean the difference between life & death
 all of this is analytical, i.e. quantitative chemistry


helps to understand concentrations in solutions o concentration is normally in % or mol/L o important for:
 hairstylists colouring hair
 vet techs determining dosages of meds for animals or anaesthetic
 farmers fertilizing their fields with an artificial fertilizer or herbicide
 testing water quality (the amount of Pb 2+ , Hg 1+ ,
Cl 1, Fe 2+ , etc. in a body of water)

the mole is a common quantity for all matter o mass is not a common quantity
 e.g., 1 kg of lead vs. 1 kg of feathers o the mole measures the # of particles

the mole is a common measurement for chemists, like how we use a dozen to measure a quantity of eggs
 to understand particles, it’s useful to understand how they behave

there are 5 postulates (points) that all matter abides by:
1. All matter is made up of tiny particles that we call atoms.
2. All particles of one substance are the same. Different substances are made up of different particles.
3. Particles attract each other.

4. Particles are always moving. The more energy they have, the faster they move.
5. Particles at higher temperatures move faster than those at lower temperatures.

there are 3 ways particles can move: i. translate = move forward/back/left/right ii. vibrate = particles are pulsing, not really moving iii. rotate = turning but not really moving
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to summarize, all matter is made of particles that we call atoms o these particles are always in motion, even in a solid state o warmer particles take up more space than cold ones o warmer particles move faster than cold particles o when moving particles hit stationary objects, they create pressure

all states of matter can cause pressure o we’ll focus on gases for the first part of this unit
 focus is on gases because that’s where the concept of the mole started with

gases are affected by: a) temperature

measured in °C, K o the higher the temp., the faster they move and the more they expand
 warmer gas molecules occupy more space than cold ones
 if a gas is in a rigid container, molecules will bounce against the walls of it, increasing pressure within the container

b) pressure

measured in kPa, psi, mmHg or torr o is the amount of force applied per unit area o kPa is a derived unit (is N/m 2 = Pa)
 Pa = pascal, the SI base unit for pressure o old units of measurement are psi, mm Hg / torr
 psi still used for tire pressure
 mmHg used in medicine (sphygmomanometer) c) volume

measured in L, mL, m 3 , cm 3

because gases are affected by temperature & pressure, chemists needed to establish standard temperature & pressure values so they could compare results of different experiments on gases o this lead to STP, which is 0°C & 101.325 kPa

101.325 kPa is the same as 14.7 psi (psi, pounds per square inch, is the imperial unit of measuring pressure) o so just think: there is almost 15 lbs of pressure pushing against every square inch of your body at all the time!
 what would happen to us if we didn’t have that
15 psi pushing on us all the time???

the opposite of STP is RTP, relative temperature & pressure o temp is 25 °C, not 0°C


temperature o sometimes Kelvin (K) is preferable to degrees
Celsius ( °C) because there’s no “-” when using K o convert
°C to K
 add 273 to °C measurement to get temp. in K

pressure o 1 atmosphere = 101.325 kPa
= 14.7 psi
= 760 or mmHg o convert psi to kPA
DEMOS

vacuum jar (foam, marshmallow, balloon)

pop can crusher o heat pop can with water in it on a hot plate, then plunge it into ice water o Youtube “can crushing experiment” o Youtube “air pressure train car”

break the stick under the newspaper

2 balloons connected, 1 large/1 small
(stick the necks together)