chemistry chapter 1 -2. what is matter matter: anything that has mass and volume ex: air we...
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ChemistryChemistry
Chapter 1 -2Chapter 1 -2
What is MatterWhat is Matter
Matter:Matter: Anything that has mass and volumeAnything that has mass and volume
Ex:Ex: Air we breathe Air we breathe
When we blow up a balloon it has more mass When we blow up a balloon it has more mass and a greater volume than when it was deflated and a greater volume than when it was deflated
What is Matter?What is Matter?
Volume:Volume: Space that an object occupiesSpace that an object occupies
Ex:Ex: Textbook – It takes up spaceTextbook – It takes up space How do we measure the volume of a liquid?How do we measure the volume of a liquid?
Must be read the same way EVERY time!Must be read the same way EVERY time!
What is Matter?What is Matter?
Mass:Mass: Quantity of matter in an objectQuantity of matter in an object
How do we measure mass?How do we measure mass? Electronic balanceElectronic balance Triple beam balance’Triple beam balance’
Mass is related but not identical to weightMass is related but not identical to weight
What is Matter?What is Matter?
Weight:Weight: Force produced by gravity acing on massForce produced by gravity acing on mass
The weight of an object depends on where it is. The weight of an object depends on where it is. Whereas the mass of an object will always be the Whereas the mass of an object will always be the same no matter where it is in the universe.same no matter where it is in the universe.
Ex: An astronaut weighs about 6 times more on Earth Ex: An astronaut weighs about 6 times more on Earth than on the moon because the effect of gravity is less than on the moon because the effect of gravity is less on the moon. His mass though remains constant!on the moon. His mass though remains constant!
Units of MeasurementUnits of Measurement
In class we will use quantitative terms – In class we will use quantitative terms – numbers – to make descriptions more numbers – to make descriptions more accurate.accurate. Ex. 15 grams of sugar instead of a spoonfulEx. 15 grams of sugar instead of a spoonful
Quantity:Quantity: Has magnitude or sizeHas magnitude or size
Unit:Unit: Standard used when measuring a quanityStandard used when measuring a quanity
Units of MeasurementUnits of Measurement
Ex. You can measure the quantity mass Ex. You can measure the quantity mass with the unit kilogram. with the unit kilogram.
What quantity is measured with the unit What quantity is measured with the unit meters?meters?
Units of MeasurementUnits of Measurement
In 1960 the standard system of In 1960 the standard system of measurement units was adoptedmeasurement units was adopted
There are 7 base units which you can There are 7 base units which you can find in Table 1-3 on page 12find in Table 1-3 on page 12
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Units of MeasurementUnits of Measurement
We will be converting from 1 unit to We will be converting from 1 unit to another another
Conversion Factor:Conversion Factor: Mathematical expression that relates two Mathematical expression that relates two
unitsunits
Ex: Convert 1.5 kg to grams Ex: Convert 1.5 kg to grams
Units of MeasurementUnits of Measurement
Derived units:Derived units: Created from combinations of the base SI Created from combinations of the base SI
unitsunits
VolumeVolume Multiple length, width, and the height of an Multiple length, width, and the height of an
objectobject m x m x m = m^3m x m x m = m^3 Make sure when converting to do it 3 times to Make sure when converting to do it 3 times to
end up in m^3end up in m^3
Units of MeasurementUnits of Measurement
1000 cm^31000 cm^3 0.001 m^30.001 m^3 1000000 mm^31000000 mm^3
All of these equal 1 LAll of these equal 1 L
Properties of MatterProperties of Matter
Relationships between properties can be Relationships between properties can be represented by graphingrepresented by graphing
When you look at the graph on page 15 When you look at the graph on page 15 what do you notice?what do you notice?
The mass of the aluminum is directly The mass of the aluminum is directly proportional to its volumeproportional to its volume
Properties of MatterProperties of Matter
The slope of the line equals the ratio of The slope of the line equals the ratio of mass mass
Slope = y2 – y1/ x2 – x1Slope = y2 – y1/ x2 – x1
Density:Density: Ratio of mass to volumeRatio of mass to volume Density = mass / volumeDensity = mass / volume
DensityDensity
Unit for density is g/cm^3Unit for density is g/cm^3
Look at Figure 1-11 Look at Figure 1-11 Which substances have a density of less than 1 and Which substances have a density of less than 1 and
how do you know?how do you know?
We can also use density to figure out mass or We can also use density to figure out mass or volumevolume D X V = mD X V = m m / D = Vm / D = V
DensityDensity
If you found a bracelet on the street and you If you found a bracelet on the street and you wanted to find out if it was made of real silver wanted to find out if it was made of real silver what would be your first step?what would be your first step? Mass = 199.0 gMass = 199.0 g Volume = 20.5 cm^3Volume = 20.5 cm^3 D = m / VD = m / V
199.0 g / 20.5 cm^3 = 9.71 g/cm^3199.0 g / 20.5 cm^3 = 9.71 g/cm^3 Look at Table 1-5 to find the density of silver and Look at Table 1-5 to find the density of silver and
determine if the bracelet is actually made of silverdetermine if the bracelet is actually made of silver
Physical PropertiesPhysical Properties
Physical Property:Physical Property: Any property of matter that can be measured Any property of matter that can be measured
without changing its chemical nature. without changing its chemical nature.
Ex: Mass, volume, and densityEx: Mass, volume, and density Ex: Color, texture, melting point, and boiling Ex: Color, texture, melting point, and boiling
pointpoint
Physical PropertiesPhysical Properties
Physical Changes:Physical Changes: Change that affects only the physical Change that affects only the physical
propertiesproperties
Ex: Melt water to get ice Ex: Melt water to get ice you still have you still have H2OH2O
Ex: Boil water to get steamEx: Boil water to get steam
Physical ChangesPhysical Changes
Physical changes can involve changes in Physical changes can involve changes in energyenergy
Melting & Boiling are endothermic Melting & Boiling are endothermic changes because heat is transferred to changes because heat is transferred to the substance from the surroundingsthe substance from the surroundings
Freezing & Condensation are exothermic Freezing & Condensation are exothermic changes because heat is transferred changes because heat is transferred from the substance to its surroundings. from the substance to its surroundings.
Chemical PropertiesChemical Properties
Chemical Property:Chemical Property: Property of matter that can be observed only Property of matter that can be observed only
when substances interact with one another. when substances interact with one another.
Chemical Change:Chemical Change: A change that produces one or more new A change that produces one or more new
substances. substances.
Chemical PropertiesChemical Properties
Evidence a chemical change has Evidence a chemical change has occurred. occurred.
1.1. The evolution of a gas- we can see gas The evolution of a gas- we can see gas bubbling or the emission of an odor.bubbling or the emission of an odor.
2.2. Formation of a precipitate – insoluble Formation of a precipitate – insoluble solidsolid
3.3. Evolution or absorption of heat – Evolution or absorption of heat – increase or decrease in temperatureincrease or decrease in temperature
Chemical PropertiesChemical Properties
4. The emission of light – light is produced4. The emission of light – light is produced
5. Color change – look at Figure 1-13 letter 5. Color change – look at Figure 1-13 letter d. This shows the color change of an d. This shows the color change of an indicator in the presence of a base. indicator in the presence of a base.