Science - Chemistry | Test #8

Question 1

What test do scientists use to measure the pH of something?

Answer 1

Litmus Test
First completed naturally using the extracts from some lichen species.

Can be completed at home using boiled Red Cabbage.

Question 2

pH Background

Answer 2

“pH” stands for “pouvoir Hydrogène” or Hydrogen Power
pH measures 3 levels on a scale from 0-14
Acids, Bases (Alkali), and Neutral

Question 3

Acids

Answer 3

Acids are chemicals that are composed mainly of Positive Hydrogen Atoms
Acids range from 0-7 on the pH Scale,
with the strongest(0) to weakest(7)

Question 4

Bases (Alkali)

Answer 4

Bases are chemicals that are mainly composed of Negative Oxygen-Hydrogen Atoms
Bases range from 7-14, strongest bases (14)to weaker bases (7)

Question 5

Neutrals

Answer 5

Neutral Chemicals are ones that are closer to 7
Distilled Water is considered the most neutral chemical with a pH exactly at 7
Acids and Bases of equal strength have the ability to neutralize each other, which usually results in a chemical ~7

Question 6

On the pH Scale, which numbers are associated with Acids, Bases and neutral?

Answer 6

Numbers 0-7 are associated with Acids

Numbers 7-14 are associated with Bases

The number 7 is associated with Neutral chemicals

Question 7

Synthesis

Answer 7

A synthesis reaction will allow two or more particles to combine into a single molecule
Most synthesis chemical reactions will be based on Covalent Bonds which allow atoms to share electrons with other atoms
e.g. Water
It is the synthesis of hydrogen and oxygen atoms

Question 8

Decomposition

Answer 8

Breaking down of molecules into smaller particles or atoms

e.g. Photosynthesis

Light Energy creates a chemical reaction that allows for water molecules and carbon dioxide molecules to break apart, and eventually become Glucose and Oxygen

Question 9

Combustion

Answer 9

substance reacting to Oxygen
Combustion usually involve Hydrocarbons as the main fuel source such as Methane, Propane, or Butane
The byproducts of most combustion reactions: Carbon Dioxide, Water, Heat and Light

Question 10

What is a Synthesis Chemical Reaction

Answer 10

A chemical reaction where you merge moleclues or atoms

Question 11

How does Temperatuure affect gas solutions

Answer 11

Increase temp = density decrease
Decrease temp = density increase

Question 12

What gas is associated with decompression sickness(aka the Bends)

Answer 12

nitrogen where an increase in pressure outside the body forces nitrogen to be absorbed in the tissue
If the nitrogen is not released slowly back into the bloodstream,creates nitrogen bubbles(joint pain, dizziness, and paralysis)

Question 13

What does an oxidizer do in Combustion

Answer 13

Sustains the combustion reaction

Question 14

Is Fire a Solid, Liquid, or Gas?

Answer 14

Fire is neither a Solid, Liquid, nor Gas, but a visual result of Combustion

Question 15

Combustion Elements

Answer 15

oxygen, fuel and heat source

Question 16

Fuel combustion

Answer 16

Fuels for combustion will often contain Hydrocarbons such as Methane or Butane, but they can also have resources such as Sugars

key element in a Fuel’s quality, accessible Hydrogen

Question 17

Oxidizer

Answer 17

Oxygen, it helps sustain or intensify the rate of Combustion

The Oxidizer will provide oxygen atoms that will combine with other atoms to create new molecules

Question 18

The third element in Combustion is a …

Answer 18

Heat Source

The Heat Source helps initiate the combustion reaction by allowing the atoms of the Fuel to be released from their bonds

The released atoms from the Fuel will combine with the oxygen atoms from the Oxidizer to produce Energy (Heat and Light), Carbon Dioxide, and Water

Question 19

Who is credited with creating the first modern Internal Combustion Engine?

Answer 19

The German Nicolaus Otto developed the
Internal Combustion Engine in 1876

Question 20

Types of Combustion Engines

Answer 20

External Combustion Engine
Internal Combustion Engine

Question 21

External Combustion Engine

Answer 21

The Combustion is created away from the moving mechanisms, and the energy is transferred to the engine

An example is a Steam Engine

The Boiler in steam engines allows for the heating of water, which will create an expansive gas that drive a piston to move

Question 22

Internal Combustion Engine

Answer 22

The Internal Combustion Engine works similarly to the general design of a Steam Engine, but creates the heat source within the engine instead of from an external source

The Piston creates a compressed chamber for the fuel-air mixture, and a spark-plug ignites the mixture, which forces the piston to move downwards

Question 23

Some Internal Combustion Engines provide
…

Answer 23

Continuous Combustion

Question 24

Continuous Combustion

Answer 24

An example would be Jet Engines

The Intake Air is compressed into the Combustion Chamber to provide constant Oxygen to allow for constant combustion

The combustion will create enough energy to spin turbines and create Thrust

Question 25

What is the purpose of the Pea in an Aerosol Can?

Answer 25

The Pea (usually a glass marble), is used to help mix the gases and liquids together

Question 26

What are the two main factors that affect the solubility of gas solutions?

Answer 26

Temperature and Pressure

Question 27

How does Temerature affect the solubility of gas solutions?

Answer 27

As temperature increases in a gas solution, the solubility of the solubility of the solution decreases, allowing for greater separation of the components of the solution

Question 28

How does Pressure affect gas solutions?

Answer 28

When external pressure is applied to a gas solution, it increases the solubility of the solution and allows for a greater mixture of the solution

Question 29

What are gases that aren't naturally reactive called?

Answer 29

Noble or Inert Gases

Question 30

What are some examples of Noble/Inert Gases?

Answer 30

Helium Neon Argon Krypton Xenon Radon

Question 31

What are gases like Argon ideal for and why?

Answer 31

What: Incandescent light bulbs Why: Since they wouldn't react to the heat from the tungsten filament and would also help slow the erosion of the filament

Question 32

What can Inert Gases also react to and what does it do?

Answer 32

What it reacts to: Electrical currents What it does: Forces the electrons of the gas to agitate and produce light

Question 33

What part of Red Blood Cells carry Oxygen and Carbon Dioxide?

Answer 33

Hemoglobin allows oxygen and carbon dioxide to bind with the red blood cells, and release the gases at the appropriate times

Question 34

What happens when

Answer 34

The lower the pressure in the lungs relative to outer environment, the more likely that air will be inhaled

Question 35

Ionic bond:

Answer 35

when something bonds but one is missing electrons or has too many

Question 36

photosynthesis decompisition

Answer 36

(e.g photosynthesis, eggs) Light energy creates a chemical reaction that allows for water molecules and carbon dioxide molecules to break apart, and eventually become glucose and oxygen

Question 37

Lowering of air pressure

Answer 37

lowering the diaphragm muscle

Question 38

Exhalation of carbon dioxide

Answer 38

the pressure of the gas itself within the lungs allows it to exhaled Dalton’s Law: “each gas within a solution exerts its own pressure relative to its concentration in the solution”

Question 39

Oxygen can be lethal for humans if

Answer 39

the pressure is twice as normal, The excess oxygen molecules can start to bind with tissues and cause the erosion of the tissue early symptoms: coughing, blurred vision and nausea red if received too much oxygen, Blue/purple when not receiving enough oxygen

Question 40

Carbon dioxide can be lethal for humans if

Answer 40

air inhaled is at least 10-15% Signs : dizziness, headaches, loss of consciousness