Unit 2

Question 1

What two forms of matter formed right after the big bang approximately 13.7 billion years ago?

Answer 1

Quarks and electrons

Question 2

What formed protons and neutrons?

Answer 2

Quarks formed protons and neutrons

Question 3

What is our star made mostly of?

Answer 3

Our star is mostly made out of hydrogen

Question 4

What reaction combines atoms to make bigger atoms in stars?

Answer 4

The reaction that combines atoms to make bigger atoms in stars is nuclear fusion.

Question 5

What is the maximum sized atom that can be made in a star before it collapses?

Answer 5

The maximum sized atom that can be made in a star is iron.

Question 6

What is the origin of all the other atoms?

Answer 6

The origin in all other atoms is the big bang

Question 7

What are the 4 most common elements in living organisms? (over 90%)

Answer 7

The four most common elements are carbon, hydrogen, oxygen, and nitrogen.

Question 8

What does the atomic number tell you about the atom?

Answer 8

It tells you the number of protons in the nuclei

Question 9

How do you know how many electrons an atom has?

Answer 9

You have to look at its atomic number

Question 10

How does the atomic mass tell you how many neutrons are in the atom?

Answer 10

It represents the sum of protons and neutrons.

Question 11

What is in the nucleus of an atom?

Answer 11

Protons and neutrons are in the nucleus of an atom

Question 12

How many electrons max can be held in the first orbital around the nucleus? The second? The third?

Answer 12

The first orbital can hold 2, the second orbital can hold 8, and the third orbital can hold 18.

Question 13

Why do bonds form?

Answer 13

It allows them to reach the most stable state they can get.

Question 14

Why do ions form?

Answer 14

Ions form when an atom loses or gains electrons.

Question 15

What kind of bonds form between two ions?

Answer 15

Ionic bonds form between 2 ions

Question 16

What type of bond forms when the electrons are being shared?

Answer 16

Covalent bonds happen when electrons are shared

Question 17

What 4 atoms make 1, 2, 3, 4 covalent bonds?

Answer 17

Hydrogen, oxygen, nitrogen, and carbon

Question 18

Why is water considered a polar molecule?

Answer 18

It is considered a polar molecule because of the uneven distribution of the electrons

Question 19

What are the bonds between water molecules called?

Answer 19

They are called hydrogen bonds

Question 20

Distinguish cohesion from adhesion.

Answer 20

Cohesion is two of the same molecule forming bonds while adhesion is two different molecules forming bonds.

Question 21

What is transpiration?

Answer 21

Transpiration is the process where plants release water into the atmosphere

Question 22

Why does ice float?

Answer 22

It floats because it is less dense than water

Question 23

What does it take so much energy to heat water?

Answer 23

It takes so much energy because we need to break the hydrogen bonds

Question 24

What is the percentage of water in a human body?

Answer 24

70% is the percentage of water in a human body

Question 25

Why does water have such a high heat of vaporization?

Answer 25

It's because they have to break the strong hydrogen bonds

Question 26

What is the solute and solvent in ocean water?

Answer 26

Water is the solvent and salt is the solute

Question 27

What are the two ions of water?

Answer 27

Oxygen- and hydrogen +

Question 28

Which one is usually measured? Hydrogen+ or Oxygen-

Answer 28

Hydrogen +

Question 29

What is the pH scale?

Answer 29

The pH scale measures how acidic or basic a substance is, ranging from 0 to 14, with a pH of 7 considered neutral; a pH less than 7 indicates an acid, while a pH greater than 7 indicates a base

Question 30

What do we call chemicals that can resist pH change?

Answer 30

We call them buffers

Question 31

What is the pH range in human blood?

Answer 31

Although the pH of blood ranges from 7.35-7.45, the pH levels drop below 6.9, it can lead to coma.

Question 32

What pH buffers do we have in our body?

Answer 32

The primary pH buffer system in the human body is the bicarbonate buffer system

Question 33

How does fast breathing affect the pH of your blood?

Answer 33

Rapid breathing can raise your blood pH by causing you to exhale too much carbon dioxide, which is known as respiratory alkalosis.

Question 34

What is the pH of your stomach?

Answer 34

It is between 1.5 and 3.5

Question 35

Why do people take TUMS?

Answer 35

People take TUMS because it's an antacid that neutralizes stomach acid to treat heartburn, indigestion, and upset stomach.

Question 36

In general, foods are normally considered acidic, neutral or basic?

Answer 36

Foods are mainly considered acidic

Question 37

Why is the ocean acidifying?

Answer 37

The ocean is acidifying because it absorbs large amounts of carbon dioxide from the atmosphere

Question 38

How does acid rain affect forests?

Answer 38

Acid rain that seeps into the ground can dissolve nutrients, such as magnesium and calcium, that trees need to be healthy.

Question 39

Why is carbon the central atom in organic molecules?

Answer 39

Carbon is the central atom in organic molecules because it has the unique ability to form four covalent bonds with other atoms

Question 40

What atom most commonly bonds with carbon chains?

Answer 40

The atom that most commonly bonds with carbon chains is hydrogen

Question 41

Why are certain atoms called functional groups?

Answer 41

They are responsible for the characteristic chemical reactions of a molecule

Question 42

Distinguish monomer from polymer.

Answer 42

Monomers are simple molecules that are the building blocks of polymers, which are large molecules made up of many monomers

Question 43

What reaction bonds monomers?

Answer 43

Dehydration bonds monomers

Question 44

What reaction splits polymers?

Answer 44

The reaction that breaks down polymers is called hydrolysis

Question 45

What is the energy in kcal/g for carbohydrates, proteins and fats?

Answer 45

Carbohydrates provide 4 calories per gram, protein provides 4 calories per gram, and fat provides 9 calories per gram.

Question 46

free question yay

Answer 46

:)

Question 47

Which reaction do our digestive enzymes use?

Answer 47

Digestive enzymes primarily use a hydrolysis reaction to break down food molecules into smaller components during digestion

Question 48

What are the monosaccharides of carbohydrates?

Answer 48

The monosaccharides of carbohydrates are the simplest units of sugar, including glucose, fructose, and galactose

Question 49

What are the three most common disaccharides?

Answer 49

The three most common disaccharides are sucrose, lactose, and maltose

Question 50

What are the structural polysaccharides?

Answer 50

The primary structural polysaccharide is cellulose, found in plant cell walls, while the energy storage polysaccharide in plants is starch and in animals is glycogen

Question 51

How do you test for the presence of a mono/di saccharide?

Answer 51

To test for the presence of monosaccharides or disaccharides, you can use the Barfoed's test or Benedict's test

Question 52

How do you test for the presence of a starch?

Answer 52

To test for the presence of starch, you can use an iodine solution, which will turn blue-black when it reacts with starch

Question 53

Explain the symbiosis between fruits and animals.

Answer 53

Some plants depend on animals to help spread their seed.

Question 54

Why can we thank plants for our amazing color vision?

Answer 54

Color can even be an indicator of plant nutrition and overall plant health.