Chapter 1.1: What is matter?
What are some examples of a physical change?
1. A solid may melt 2. Alcohol in a thermometer may change volume as the temperature changes.
examples of how chemistry impacts your everyday life:
1. If you take a shower or bath in the morning, you probably use soap, shampoo, or both. These items contain chemicals that interact with the oil and dirt on your body and hair to remove them and wash them away. Many of these products also contain chemicals that make you smell good; they are called fragrances. 2. When you brush your teeth in the morning, you usually use toothpaste, a form of soap, to clean your teeth. Toothpastes typically contain tiny, hard particles called abrasives that physically scrub your teeth. Many toothpastes also contain fluoride, a substance that chemically interacts with the surface of the teeth to help prevent cavities. 3. Perhaps you take vitamins, supplements, or medicines every morning. Vitamins and other supplements contain chemicals your body needs in small amounts to function properly. Medicines are chemicals that help combat diseases and promote health 4. Perhaps you make some fried eggs for breakfast. Frying eggs involves heating them enough so that a chemical reaction occurs to cook the eggs. 5. After you eat, the food in your stomach is chemically reacted so that the body (mostly the intestines) can absorb food, water, and other nutrients. 6. If you drive or take the bus to school or work, you are using a vehicle that probably burns gasoline, a material that burns fairly easily and provides energy to power the vehicle. Recall that burning is a chemical change.
Which of the following is matter and not matter? 1. a hot dog 2. love 3. a tree
1. Matter: A hot dog has mass and takes up space, so it is matter. 2. NOT matter: Love is an emotion, and emotions are not matter. 3. Matter: A tree has mass and takes up space, so it is matter.
What are some examples of compounds?
1. water 2. penicillin 3. sodium chloride (the chemical name for common table salt).
What is a Physical Change?
A change that occurs when a sample of matter changes one or more of its physical properties.
What are Chemical Properties?
A characteristic that describes how matter changes form in the presence of other matter.
What are Physical Properties?
A characteristic that describes matter as it exists.
What is a compound?
A combination of more than one element.
What is a homogeneous mixture?
A combination of two or more substances that is so intimately mixed that the mixture behaves as a single substance (another name = solution)
What is a heterogeneous mixture?
A mixture composed of two or more substances.
What is a mixture?
A physical combination of more than one substance.
What is an element?
A substance that cannot be broken down into simpler chemical substances by ordinary chemical means.
What is a metal?
An element that conducts electricity and heat well and is shiny, silvery, solid, ductile, and malleable. 1. Element 2. conducts electricity and heat well 3. shiny and silvery 4. malleable (can be pounded into thin sheets) 5. ductile (can be drawn into thin wires) 6. solid at room temperature (although mercury is a well-known exception)
What is a nonmetal?
An element that exists in various colors and phases, is brittle, and does not conduct electricity or heat well. 1. Element 2. Does NOT conduct electricity or heat well 3. Exists in various colors and phases (At room temperature) 4. Brittle when solid 5. Cannot be pounded into thin sheets (not malleable) 5. Cannot be drawn into thin wires (not ductile)
What is a semimetal?
An element that has properties of both metals and nonmetals.
What is Matter?
Anything that has mass and takes up space.
Physical change or a chemical change? Bread dough becomes fresh bread in an oven.
Chemical change Because of the oven's temperature, chemical changes are occurring in the bread dough to make fresh bread. These are chemical changes. (In fact, a lot of cooking involves chemical changes.)
The fact that this match burns is a ___________________ of the match.
Chemical property
Key Takeaway: _________ is the study of matter and its interactions with other matter and energy.
Chemistry
Identify the following combination as a heterogeneous mixture or homogeneous mixture. a mixture of iron metal filings and sulfur powder (Both iron and sulfur are elements.)
Heterogeneous mixture Assuming that the iron and sulfur are simply mixed together, it should be easy to see what is iron and what is sulfur, so this is a heterogeneous mixture.
Identify the following combination as a heterogeneous mixture or homogeneous mixture: soda water (Carbon dioxide is dissolved in water.)
Homogeneous mixture Because carbon dioxide is dissolved in water, we can infer from the behavior of salt crystals dissolved in water that carbon dioxide dissolved in water is (also) a homogeneous mixture.
if you take salt crystals and dissolve them in water, it is a ___________ ____________?
Homogeneous mixture or solution The salt dissolved in water is a homogeneous mixture, or a solution because it is very difficult to tell that you have more than one substance present just by looking—even if you use a powerful microscope
What are some examples of elements?
Iron, carbon, and gold
Key Takeaway: ________ is anything that has mass and takes up space.
Matter
What is a substance?
Matter that has the same physical and chemical properties throughout. (Sometimes the phrase pure substance is used, but the word pure isn't needed.)
With what key terms can matter be broken down?
Matter: element, compound, one substance, more than one substance, heterogeneous mixture, homogeneous mixture
Physical change or a chemical change? Water in the air turns into snow.
Physical change Because the water is going from a gas phase to a solid phase
Physical change or a chemical change? A person's hair is cut.
Physical change Your long hair is being shortened.
What are the two basic ways to describe matter?
Physical properties and chemical properties
What is the first example of how certain fields define terms in specific ways?
The definition of the term "substance" as used in chemistry In many cases, the usage within the field is different from how that same term is used in daily life.
What is a Chemical Change?
The process of demonstrating a chemical property. (As the matter in the match burns, its chemical composition changes, and new forms of matter with new physical properties are created. Note that chemical changes are frequently accompanied by physical changes, because the new matter will likely have different physical properties from the original matter.)
What is Chemistry?
The study of the interactions of matter with other matter and with energy.
Key Takeaway: Physical properties and chemical properties of matter can __________.
change
Key Takeaway: Matter is _________ _____ elements and compounds.
composed of
Key Takeaway: Matter can be _______ in terms of physical properties and chemical properties.
described
The physical and chemical properties of a compound are ______________ from the physical and chemical properties of its constituent elements; that is, it behaves as a completely ____________ _____________
different; different substance
A physical change _________ affect the chemical composition of matter. "does" or "does not"?
does not
__________ ___________(left photo) is the only metal that exists as a liquid at room temperature. It has all the other expected properties of a metal. ___________ __________(right photo) is a yellow nonmetal that usually is found as a powder.
elemental mercury; elemental sulfur
Chemistry recognizes two different types of substances, what are they?
elements and compounds
Key Takeaway: ___________ can be _______ as metals, nonmetals, and semimetals.
elements; described
a combination of salt and steel wool is a ____________ ____________
heterogeneous mixture because it is easy to see which particles of the matter are salt crystals and which are steel wool.
What are the two types of mixtures?
heterogeneous mixture and homogeneous mixture
What is another name for a semimetal?
metalloids
We can usually divide elements into _______ and _______, and each set shares certain (but not always all) properties.
metals and nonmetals
Just about everything we come into contact with is a _______ of some sort.
mixture
Key Takeaway: Combinations of different substances are called _________
mixtures
An important physical property is the _____________ (or _______) of matter.
phase (or state)
Each element has its own unique set of ____________ and __________ ______________
physical and chemical properties
Solid ice melting into liquid water is an example of a ________________
physical change
What are some examples of physical characteristics of matter?
shape, color, size, and temperature.
What are the phases of matter?
solid, liquid and gas
Another word for a homogeneous mixture is ___________
solution
