FLAME TEST AND CHEMICAL AND PHYSICAL TEST

Question 1

study of matter and the changes it undergoes

Answer 1

Chemistry

Question 2

Chemistry is the study of matter and the changes it undergoes. These changes can be broken down into two classes

Answer 2

Physical Change and Chemical change

Question 3

Grinding, melting, dissolving, and evaporating all are all what kind of change

Answer 3

Physical Change

Question 4

change results in the formation of one or more “new” substances. These new substances differ in chemical properties and composition from the original substance

Answer 4

Chemical Change

Question 5

The rusting of iron and the burning of paper are two examples of

Answer 5

Chemical Change

Question 6

an insoluble solid that emerges from a liquid solution

Answer 6

Precipitate

Question 7

The emergence of the insoluble solid from solution is called

Answer 7

Precipitation

Question 8

Often the precipitate emerges as a

Answer 8

Suspension

Question 9

this can form when two soluble salts react in solution to form one or more insoluble products

Answer 9

Precipitates

Question 10

can also form insoluble solid when the temperature of a solution is lowered

Answer 10

precipitate

Question 11

reduce the solubility of salts, which may result in their precipitation as solids

Answer 11

Lower Temperature

Question 12

the formation of gas bubbles in a liquid by a chemical reaction

Answer 12

Effervescence

Question 13

the release of carbon dioxide which bubbles as a gas from the liquid when limestone chips, which are composed of calcium carbonate, are added to dilute hydrochloric acid. It is an example of

Answer 13

Effervescence

Question 14

process resulting from random motion of molecules by which there is a net flow of matter from a region of high concentration to a region of low concentration

Answer 14

Diffusion

Question 15

meaning that this is completely saturated with carbon dioxide (CO2). Thus, the fizz is not effervescence, not a chemical change.

Answer 15

Carbonated drinks, such as soda, are in a state of supersaturation

Question 16

theorized that electrons have specific energy values

Answer 16

Bohr

Question 17

Bohr theorized that electrons have specific energy values, which he called

Answer 17

Energy levels

Question 18

meaning that only specific energy levels were possible around the nucleus of an atom

Answer 18

Quantized

Question 19

can absorb energy and undergo a transition to a higher energy level

Answer 19

electron in a low energy level

Question 20

True or False: Electrons move between energy levels by gaining or losing a specific amounts of energy. When this occurs, we say that the electron undergoes a transition from one energy level to another.

Answer 20

True

Question 21

When that electron returns to the ground state, what will happen

Answer 21

it loses energy by emitting a photon

Question 22

which is a tiny particle that behaves like a wave and travels at the speed of light

Answer 22

photon

Question 23

a procedure used to test qualitatively for the presence of certain metals in chemical compounds

Answer 23

flame test

Question 24

the presence of a potassium ion in a compound will color a flame

Answer 24

violet

Question 25

sodium ions in a compound produce a very strong what color flame

Answer 25

yellow

Question 26

the range of frequencies of electromagnetic radiation and their respective wavelengths and photon energies

Answer 26

Electromagnetic Spectrum

Question 27

7 types of electronic radiation

Answer 27

1. Radio Waves 2. Microwave 3. Infrared Radiation 4. Visible Light 5. Ultraviolet Radiation 6. X-ray 7. Gamma Ray

Question 28

a particular type of electromagnetic radiation that can be seen and sensed by the human eye, but this energy exists at a wide range of wavelengths

Answer 28

Light

Question 29

the basic unit for measuring the wavelength of electromagnetic waves

Answer 29

Micron

Question 30

The shortest waves which have wavelengths of 10e-6 microns or less

Answer 30

Gamma Rays

Question 31

The longest waves which have wavelengths of many kilometers

Answer 31

Radio Waves

Question 32

The range of visible consists of the narrow portion of the spectrum, from

Answer 32

0.4 microns (blue) to 0.7 microns (red)

Question 33

the portion of the electromagnetic spectrum that is visible to the human eye

Answer 33

Visible Spectrum

Question 34

The visible spectrum is the portion of the electromagnetic spectrum that is visible to the human eye. Electromagnetic radiation in this range of wavelengths is called

Answer 34

visible light or simply light

Question 35

A typical human eye will respond to wavelengths from about

Answer 35

380 to 740 nanometers

Question 36

Give the color: 400-430 nm

Answer 36

Violet

Question 37

Give the color: 430-490 nm

Answer 37

Blue

Question 38

Give the color: 490-560 nm

Answer 38

Green

Question 39

Give the color:

Question 40

Give the color: 560-580 nm

Answer 40

Yellow

Question 41

Give the color: 580-620 nm

Answer 41

Orange

Question 42

Give the color: 620-800 nm

Answer 42

Red

Question 43

a term meaning to "carry along gently as through the air"

Answer 43

Waft

Question 44

The term is commonly used to describe scents that have diffused into other parts of a room, or to describe smoke as being seen moving through the air

Answer 44

Waft

Question 45

Wafting may be used for everyday substances, to make sure they are

Answer 45

fresh, or consumable

Question 46

pass or cause to pass easily or gently through or as if through the air

Answer 46

Waft

Question 47

protein obtained by boiling skin, tendons, ligaments, and/or bones with water. It is usually obtained from cows or pigs

Answer 47

Gelatin

Question 48

gases which stays lightly over water are called

Answer 48

wafting gas

Question 49

These gases are harmful for people leaving in coastal areas. They are mainly released from industries and cause breathlessness; They are often colourless with pungent smell

Answer 49

Wafting gas

Question 50

When you are in the laboratory and take a direct sniff of the chemicals you are using, you run the risk of damaging your, what part

Answer 50

mucous membranes or your lungs

Question 51

an odor in a laboratory is best done using the technique of

Answer 51

Wafting

Question 52

involves drawing one’s hand across the opening of a container in order to push the odor towards the nose

Answer 52

Wafting

Question 53

quickly diffuse through air

Answer 53

Most gases, including noxious ones

Question 54

The lower the molecular weight of the gas, the faster its rate of what

Answer 54

Diffusion

Question 55

An increase in temperature will also increase the rate of

Answer 55

Gas Diffusion

Question 56

Gel air fresheners are able to scent the air for a long time because gelatin is a

Answer 56

polymer

Question 57

collagen, a protein that forms a matrix type structure, allowing the gelatin to hold its shape

Answer 57

polymer

Question 58

suspended in the matrix of the gel which keeps the scent trapped inside

Answer 58

fragrance oil particles

Question 59

what will happen if the gel evaporates

Answer 59

the scent particles are released from the matrix, causing a continuous scent to be released from the air freshener

Question 60

The chemical reaction in burning natural gas is the reaction of methane (CH4) with oxygen (O2) in the air. If excess oxygen is used, the products would be gaseous carbon dioxide (CO2) and gaseous water (H2O)

Answer 60

Complete Combustion

Question 61

If insufficient oxygen is available, we would have an incomplete combustion, producing

Answer 61

poisonous carbon monoxide (CO) and soot (C)

Question 62

Insufficient oxygen would also result in a cooler, yellow flame, called a

Answer 62

luminous flame

Question 63

due to small particles of soot being burned to incandescence

Answer 63

Yellow color

Question 64

what are we going to do if we need a hotter flame

Answer 64

we would need to introduce more oxygen, by mixing more air with the methane gas before combustion

Question 65

the hotter the flame what color it represents

Answer 65

blue

Question 66

what is the hottest part of the flame

Answer 66

the tip of the inner blue cone of the flame

Question 67

controls how much natural gas (methane) is piped to the Bunsen burner. When the handle is pointed straight at you, the valve is fully opened. You close the valve by turning the handle either left or right. The gas goes to the Gas Inlet through a piece of rubber tubing.

Answer 67

The Gas Valve

Question 68

at the bottom of the burner controls how much methane goes from the Gas Inlet into the Barrel

Answer 68

The Needle Valve

Question 69

control how much oxygen from the air is mixed with the methane. You adjust it by holding the Barrel (before it gets hot) and turning it either direction, to open or close the air vents. If you want a very hot flame, you would open this parts to allow a maximum amount of oxygen to mix with the methane. You might have to also use the Needle Valve to allow less methane in so that there is a higher ratio of O2 to CH4.

Answer 69

The Air Vents

Question 70

colourless, odourless gas that occurs abundantly in nature and as a product of certain human activities. This is the simplest member of the paraffin series of hydrocarbons and is among the most potent of the greenhouse gases. Its chemical formula is CH4.

Answer 70

Methane

Question 71

a chemical process in which a substance reacts rapidly with oxygen and gives off heat. The original substance is called the fuel, and the source of oxygen is called the oxidizer. The fuel can be a solid, liquid, or gas, although for airplane propulsion the fuel is usually a liquid.

Answer 71

Combustion

Question 72

the emission of electromagnetic radiation (including visible light) from a hot body as a result of its rising temperature.

Answer 72

Incandescence

Question 73

unique because the properties of water allow it to exist in all three states of matter

Answer 73

Water

Question 74

Water is usually a liquid, but when it reaches to what Fahrenheit (F), it freezes into ice.

Answer 74

32°

Question 75

the solid state of water

Answer 75

Ice

Question 76

When water reaches what F, it boils. When it begins to boil, some of the water turns into steam

Answer 76

212° F

Question 77

the gas state of water, and is also called water vapor

Answer 77

Steam

Question 78

Normally, when water reaches what F it begins to freeze.

Answer 78

32°

Question 79

it lowers the freezing point of water and is often used to melt dangerous ice off of roads and sidewalks in the winter.

Answer 79

Salt

Question 80

particles are very close together, so they cannot be squeezed. The attraction between nearby particles in a solid is usually strong. Because there are such strong bonds between the particles, solids usually have a fixed shape and a constant volume. The particles in solids cannot move freely; instead Particles in a solid they vibrate in a fixed position.

Answer 80

Solid

Question 81

particles are held together by attraction, but the bonds between them are weaker than those in solids. The particle attraction allows the particles to roll over each other, but they can’t ‘escape’. It have a fixed volume, but the rolling motion of the particles allows them to take up the shape of their container. As in solids, the particles are still very close together, so it is cannot be Particles in a liquid compressed into smaller spaces

Answer 81

Liquid

Question 82

spread out and will not stay in a container unless it has a lid. The particles have much more energy than those in solids or liquids, and are constantly moving. The attraction between the particles in this is so weak that they can move freely in all directions. They spread out and take up any space that is available, so this have no fixed shape or volume. Because of the large spaces between Particles, it can be compressed.

Answer 82

Gas

Question 83

composed of different types of atoms or molecules that are not chemically bonded

Answer 83

Mixture

Question 84

a mixture of two or more chemical substances where the various components can be visually distinguished

Answer 84

Heterogenous mixture

Question 85

a type of mixture in which the composition is uniform and every part of the solution has the same properties

Answer 85

Homogeneous mixture

Question 86

The scattering of visible light by colloidal particles. You have undoubtedly "seen" a light beam as it passes through fog, smoke, or a scattering of dust particles suspended in air. All three are examples of colloids. Suspensions may scatter light, but if the number of suspended particles is sufficiently large, the suspension may simply be opaque, and the light scattering will not occur

Answer 86

Tyndall effect

Question 87

the process that takes place when a substance (or substances) are brought into contact with each other and produce a new substance(s)

Answer 87

Chemical Reaction

Question 88

The substance (or substances) initially involved in the chemical reaction are called

Answer 88

reactants or reagents

Question 89

usually characterized by a chemical change, and they yield one or more products, which usually have properties different from the reactants

Answer 89

Chemical Reaction

Question 90

represented by Chemical Equations

Answer 90

Chemical Reaction

Question 91

balanced to show the same number of atoms of each element on each side

Answer 91

Chemical Equation

Question 92

states that matter cannot be created nor destroyed. What this means is that even though different substances are created during the process of a chemical reaction, none of the reactant atoms are lost. They are simply rearranged into the new substances

Answer 92

Law of Conservation of Mass

Question 93

any process which requires or absorbs thermal energy from its surroundings, usually in the form of heat. It may be a chemical process, such as dissolving ammonium nitrate in water, or a physical process, such as the melting of ice cubes

Answer 93

Endothermic

Question 94

describes a process or reaction that releases energy from the system to its surroundings, usually in the form of heat, but also in a form of light, electricity, or sound.

Answer 94

Exothermic