Chemistry Test on Chapter 1/2

formed at high temperatures, ionized phase of matter as found in the sun

plasma

Can elements be broken down, what about compounds?

Compounds can be broken down into simpler substances by chemical means, but Elements cannot.

separates a solid from the liquid in a hetereogernous mixture and by size

Filtration Some can be separated easily by physical means: rocks and marbles, iron filings and sulfur (use magnet). Differences in physical properties can be used to separate mixtures.

takes advantage of different boiling points

distillation

Substances are either __________ or _______.

elements, compounds

a substance without definite volume or shape and can flow

gas

ocean, one set of properties

homogenous

another form of energy light electric, elastic, nuclear, sound, gravitional, thermal, smell, chemical change, smell, firewood/rust, not irreversible boiling water bubbles= h20 bubbles are wage rvaor bubbles of water

indications of a chemical change

during any chemical reaction, the mass of the products is always equal to the mass of the reactants

law of conservation of max

during any chemical reaction, the mass of the products is always equal to the mass of the reactants, all the mass can be accounted for

law of conservation of max

definite volume but takes the shape of its container- flows

liquid

anything that takes up space

matter

atoms/molecules measurement of heat

matter temperature

components of dyes such as ink may be separated

paper chromatography

describe any part of a sample with uniform composition of properties

phase

will change the visible appearance without changing the composition of the material, includes boiling, melting cutting, bending, splitting, cracking, can be reversible or irreversible

physical change

a property that can be observed and measured without changing the material's composition examples include color, hardness, MP, BP

physical properties

started with, and on left

reactants

homogenous

same throughout, see one thing, the same solution

matter is made up of almost everything, therefore it can not be neither be created nor destroyed , concise statement that summarizes the results of many observations and experiments

scientific law

Mixxtures can be ______

separated

How many phases does a homogenous mixture consist of?

single

well-tested explanation of a broad set of observations.

theory

How many phases does a heterogenous mixture consist of?

two or more

a substance that is currently a gas, but normally a liquid or solid at room temperature what is correct, water gas or water vapor

vapor

What is the formula for density?

Formula= Mass/Volume

What are the three states of matter?

Solid, Liquid, Gas (sublimation, depostiition, melting, evaporation, boiling, condensation, freezing)

Properties of compounds are different than their components elements, due to a chemical change, the resulting compound has new and different properties

Table sugar - carbon, hydrogen, oxygen Sodium chloride - sodium, chlorine Water - hydrogen, oxygen

Properties used to describe matter can be classified as extensive or intensive

True

what is made, on right

products

developed the tools and techniques for working with chemicals

alchemists

Name indications of a chemical change.

change in temperature, smell/taste, volume, melting point.boiling point, color change, bubble of gas, formation of precipiton, oxynthesis, decomposition, cooking idation, photos, neutralization

a change where a new form of matter is formed examples include rust burn decompose ferment

chemical change

ability of a substance to undergo a specific chemical change, iron plus oxygen forms rust, so the ability to rust is a chemical property of iron, during a chemical change- also called chemical reaction, the composition of the matter always changes

chemical change

burnig wood, dissolving salt in water hemical change is any change that results in the formation of new chemical substances. At the molecular level, chemical change involves making or breaking of bonds between atoms. These changes are chemical: iron rusting (iron oxide forms) a usually irreversible chemical reaction involving the rearrangement of the atoms of one or more substances and a change in their chemical properties or composition, resulting in the formation of at least one new substance: The formation of rust on iron is a chemical change. (chemistry) any process determined by the atomic and molecular composition and structure of the substances involved e say there us a chemical change in a matter when the internal make-up (molecules) of the object changes. Unlike a physical change, chemical changes cannot be reversed. Changes that cannot be reversed are called Non-reversible Change. There are usually one or more new substances formed or created from that change. You can tell there is chemical change when it produces a gas, light, smell, fire (heat) or color change. A chemical change may also be accompanied by the formation of a solid in the form of precipitate, and in some cases, accompanied by a gain or loss of energy. A good example is the change that occurs when you fry an egg: frying an egg is chemical change Here is another example: Think of the dry wood in the fireplace. When we light the wood up, it burns gently and after a while it turns into ashes. As it burns, it produces heat, light and smoke which escapes through the chimney. The heat, light, fire and smoke are all good characteristics of a chemical reaction, which result in a completely new matter—ashes. Note that the ashes from the burning wood has an entirely new molecular composition. It can never be turned back into wood again. Here are 10 common examples of Chemical Change you can find in your home. examples of chemical changeBaking cakes examples of chemical changeRusting nails or metals or aluminium examples of chemical changeBurning wood/log or lighting a match examples of chemical changeExploding Fireworks examples of chemical changeRipening and rotting bananas examples of chemical changeDigesting food in your tummy examples of chemical changeMixing an acid with a base, producing water and a salt examples of chemical changeBaking turkey or grilling chicken examples of chemical changeChanging color of autumn leaves examples of chemical changeMilk going/gone bad... Physical change rearranges molecules but doesn't affect their internal structures. Some examples of physical change are: whipping egg whites (air is forced into the fluid, but no new substance is produced) magnetizing a compass needle (there is realignment of groups ("domains") of iron atoms, but no real change within the iron atoms themselves). boiling water (water molecules are forced away from each other when the liquid changes to vapor, but the molecules are still H2O.) dissolving sugar in water (sugar molecules are dispersed within the water, but the individual sugar molecules are unchanged.) dicing potatoes (cutting usually separates molecules without changing them.)

chemical change

change that produces mater with a different composition than the original manner change in which one or more substances are converted into different substances

chemical change

a property that can only be observed by changing the composition of the material, examples include ability to burn, decompose, ferment, reactivity, etc.

chemical properties

heat of combustion, reactivity with water, PH, and electromotive force. Properties that do change tha chemical nature of matter. reactivity with other chemicals Gas toxicity coordination number flammability enthalpy of formation heat of combustion oxidation states chemical stability Flammability - How easily something will burn or ignite, is a chemical property because you can't tell just by looking at something how easily it will burn. Fire testing is done to determine how difficult or easy it will be to get a certain material to burn. Information about flammability is used in building codes, fire codes, insurance requirements, and storing, handling, and transporting highly flammable materials. Heat of Combustion - This chemical property is the amount of energy that is released as heat when a substance is burned with oxygen. Examples of this chemical property is a calorie which converts to energy within the body and the amount of heat generated by the burning of various fuels. Toxicity - How much a substance can damage an animal, plant, cell, organ, or other organism is its toxicity. Materials with the chemical property of toxicity include lead, chlorine gas, hydrofluoric acid, and mercury. Toxicity is measured by how the lead, chlorine gas, mercury, or other substance affects the organism - basically, by how much damage it does to the organism and how quickly that damage occurs. For example, lead is a toxic substance that can damage various parts of the human body, including bones, the heart, kidneys, intestines, and the nervous and reproductive systems. Ability to oxidize - This is what takes place by gaining oxygen, losing hydrogen, or losing electrons, and is a chemical property that results in the oxidation number of a substance being changed. An example of this is rust. Over time, iron and steel (which is made of iron) will rust. However, they will rust more quickly if they are combined with pure oxygen. Examples of oxidation include the way an apple turns brown after it has been cut, the way a penny turns green, and the way a fender on a car can become rusty. Radioactivity - The emission of radiation from an atom with an unstable nucleus, is a chemical property. On the periodic table of elements, the elements that have no stable isotopes are considered radioactive. Some of the most radioactive elements are hydrogen, beryllium, carbon, calcium, cobalt, zinc and iron. Chemical stability - This chemical property in a given environment, also referred to as thermodynamic stability of a chemical system, refers to the stability that takes place when a chemical system is in its lowest energy state - a state of chemical equilibrium, or balance, with its environment. This equilibrium will last indefinitely unless something happens to change the system. Half-life - This chemical property is the amount of time it will take for half of the original substance to decay. It is used in nuclear chemistry and nuclear physics to describe the time required for half of the unstable radioactive atoms in a sample to experience radioactive decay. Each of these are chemical properties. Now you can better understand what a chemical property is. Read more at http://examples.yourdictionary.com/examples-of-chemical-properties.html#Tlz79DxdhfoAbCkO.99 Physical Changes: A physical change takes place without any changes in molecular composition. The same element or compound is present before and after the change. The same molecule is present through out the changes. Physical changes are related to physical properties since some measurements require that changes be made. Melting Point: As solid matter is heated it eventually melts or changes into a liquid state at the melting point. Ice (a solid form of water) melts at 0 oC and changes to the liquid state. Carbon dioxide melts at -56.6oC Boiling Point: As the liquid matter is heated further it eventually boils or vaporizes into a gas at the boiling point. Liquid water boils and changes into a gas, usually called steam or water vapor at 100 oC. In all three states the same molecules of water (H2O) are present. Carbon dioxide boils at -78.5oC In the graphic on the left a block of dry ice as a solid is changing to the gaseous state. The molecules of CO2 are present throughout.

chemical properties

the products will have new properties different from the reactants you started with. Arrow points from the reactants to the new products

chemical reactions

when one of more substances are changed into new substances

chemical reactions

made up of one kind of material, made by a chemical change, definite composition

compound

substances that can be broken down only by chemical methods, when broke down the pieces have completely different properties than the original compound, made of two or more atoms, chemically combined

compound

simplest kind of matter, can not be broken down any simpler and still have properties of that element, all one kind of atom

element

How can you recognize a chemical change?

energy is absorbed or released (temperature changes-hotter or colder), color changes, Gas production (bubbling, fizzing, or odor change; smoke). Formation of a Precipitate - a solid that separates from solution (won't dissolve) Irreversibility - not easily reversed. There are examples of these that are not chemical changes, e.g.boiling water bubbles

List four evidences of a chemical reaction reactants are on left, yield, product on right

energy, odor changes, color changes, gas production, formation of a precipitate-liquid turns into a solid

depends on the amount of matter in the sample, examples include mass volume, calories

extensive

What are two evidences of a chemical change

heat and light

mixture is not uniform in composition and examples include chocolate chip cookies, gravel, soil

heterogenous

not the same, different

heterogenous

ocean/oil in water

heterogenous

same composition throughout called solutions, kool aid, air, salt water, every part keep its own properties solutions are homogenous mixtures Mixed molecule by molecule, thus too small to see the different parts. Can occur between any state of matter: gas in gas; liquid in gas; gas in liquid; solid in liquid; solid in solid (alloys), etc.

homogenous

depends on the type of matter, not the amount present, examples include hardness, density, boiling point

intensive

made up of more than one kind of material, made by a physical change, variable composition

mixture

physical blend of at least two substances, have variable composition can be heterogeneous or homogenous

mixtures

crumpling a sheet of paper, melting a ice cube, he measurement of a physical property may change the arrangement of matter in a sample, but not the structure of its molecules. In other words, a physical property may involve a physical change, but not a chemical change. substances that undergo changes even though the chemical composition of the substance remains unchanged Any change that occurs without altering the chemical composition of a substance is a physical change. Physical changes can include changing the color, shape, state of matter, or volume of a substance. a usually reversible change in the physical properties of a substance, as size or shape: Examples of physical properties include mass, density, color, boiling point, temperature, and volume. Freezing a liquid is a physical change. A physical change is any change in matter that involves the substance going from one physical state to another. The reference to a physical state involves solids, liquids, and gases. When a substance undergoes a physical change it does not lose its original properties when changing from one phase to another. The types of physical changes can vary. A substance can go from a solid to a liquid, a liquid to a gas, a gas to a liquid, a liquid to a solid, a solid to a gas, or a gas to a solid. Examples of Physical changes: 1. Ice melting involves a change from a solid to a liquid and the substances maintain the properties of water because the molecules never change. 2. Water boiling is a physical change as water molecules vibrate faster, they enter the gas phase and become water vapor. 3. Rubbing alcohol left uncovered will evaporate quickly into the air. It turns to a gas but maintains the properties of alcohol. 4. Hot molten iron is a liquid and when left to cool will from solid steel and can take many forms. 5. Dissolving sugar in water is a physical change. The solid sugar never loses its properties, the molecules become separated by water and the sugar can easily be recovered by evaporating the water. hysical properties can be observed or measured without changing the composition of matter. Physical properties are used to observe and describe matter. Physical properties include: appearance, texture, color, odor, melting point, boiling point, density, solubility, polarity, and many others.

physical change

ppearance, texture, color, odor, melting point, boiling point, density, solubility, polarity, and many others. color, smell, freezing point, boiling point, melting point, infra-red spectrum, attraction (paramagnetic) or repulsion (diamagnetic) to magnets, opacity, viscosity and density. There are many more examples. Note that measuring each of these properties will not alter the basic nature of the substance. Properties that do not change the chemical nature of matter

physical properties

The two general steps in successful problem solving is effective _______________ that involves developing a plan and then _____________ that plan. What are the steps to solving numeric word problems? What are two steps to solving conceptual problems

problem solving, implementing, analyze, calculate, evaluate, analyze/solve

matter that can not flow- definite shape, and has definite volume

solid

What are the three states of matter

solid, liquid, gas