MAP Unit 2: Chemistry

What is matter?

Anything that occupies space and has mass.

What are the three states of matter?

Solid, liquid, and gas.

What is all matter composed of?

Chemical building blocks called elements.

What are examples of matter?

Humans, rocks, flowers, and trees.

What are elements?

The building blocks of matter.

Can elements be broken down into simpler substances by ordinary chemical reactions?

No, elements cannot be decomposed into simpler substances by ordinary chemical reactions.

What is an element?

A quantity of matter composed of atoms of the same type.

How many naturally occurring elements are mentioned in the notes?

92 naturally occurring elements.

How many total elements are mentioned in the notes?

109 individual elements.

How are elements represented?

By letter abbreviations derived from the first one or two letters of their Latin or English names.

Approximately how many elements are found in the human body?

26 elements.

What are the four most common elements in the human body?

Carbon, hydrogen, oxygen, and nitrogen (CHON).

What is an atom?

The smallest unit of matter that can enter into a chemical reaction.

What makes up an atom?

A nucleus and an electron cloud.

What is the nucleus of an atom?

The central part of an atom containing protons and neutrons.

What are protons?

Positively charged particles that contribute to the weight of an atom.

What charge do protons have?

Positive (+).

What determines the identity of an atom?

The number of protons.

What are neutrons?

Particles with no electrical charge that contribute to the weight of an atom.

What charge do neutrons have?

Neutral (no charge).

What is the electron cloud?

The area surrounding the nucleus where electrons move.

What are electrons?

Negatively charged particles that move around the nucleus.

What charge do electrons have?

Negative (-).

In a neutral atom, how many electrons are there compared to protons?

The number of electrons equals the number of protons.

Why is a neutral atom electrically neutral?

Because its positive protons and negative electrons balance each other.

What are ions?

Atoms that possess an electrical charge due to gaining or losing electrons.

What are electrolytes?

Ions dissolved in a solution.

What are common electrolytes in the body?

Sodium (Na+), potassium (K+), chloride (Cl-), and calcium (Ca2+).

What are the four major elements in the body?

Carbon, hydrogen, oxygen, and nitrogen.

What percentage of the human body is made up of carbon, hydrogen, oxygen, and nitrogen?

Approximately 96%.

What is a molecule?

Two or more atoms held together by covalent bonds.

Can a molecule contain atoms of the same element?

Yes. Examples include H2 and O2.

Can a molecule contain atoms of different elements?

Yes. Examples include NaCl and HCl.

What is a compound?

A substance composed of atoms of two or more different elements chemically combined.

What is an example of a compound?

Water (H2O).

Are all compounds molecules?

Yes, all compounds are molecules.

Are all molecules compounds?

No, not all molecules are compounds because molecules can contain atoms of the same element.

What is a cation?

An ion formed when an atom loses one or more electrons, creating a positive charge.

What is an example of a cation?

Sodium (Na+).

What is an anion?

An ion formed when an atom gains one or more electrons, creating a negative charge.

What is an example of an anion?

Chloride (Cl-).

What happens to electrons when atoms form chemical bonds?

Atoms share electrons or gain and lose electrons.

Why do atoms form chemical bonds?

To complete their outer electron shells and become more stable.

What is ionic bonding?

An attraction between atoms when one atom loses electrons and another atom gains electrons.

How is an ionic bond formed?

By the attraction between two oppositely charged ions.

What two types of ions form an ionic bond?

A cation and an anion.

What is an example of an ionic bond?

Na+ + Cl- = NaCl (table salt).

According to the notes, what is the strongest type of chemical bond?

Ionic bonding.

What is covalent bonding?

The sharing of electron pairs between two or more atoms.

What is a single covalent bond?

A bond formed by sharing one pair of electrons.

What is a double covalent bond?

A bond formed by sharing two pairs of electrons.

What is a triple covalent bond?

A bond formed by sharing three pairs of electrons.

Why is covalent bonding important in the body?

It forms long carbon chains that become the backbone of organic compounds.

What are the four major organic compounds formed using carbon chains?

Carbohydrates, lipids, proteins, and nucleic acids.

What are hydrogen bonds?

Weak attractions that often form between molecules when hydrogen is covalently bonded to another atom, usually oxygen or nitrogen.

How strong are hydrogen bonds compared to normal covalent bonds?

Approximately 5% as strong.

What is the purpose of hydrogen bonds?

They often serve as bridges between molecules.

What is an example of hydrogen bonding?

Bridges formed between amino acids in myoglobin.

What does pH describe?

The degree of acidity or alkalinity of a solution.

What determines the pH of a solution?

The relative amounts of hydrogen ions (H+) and hydroxide ions (OH-).

Why is pH important in the body?

Biochemical reactions are extremely sensitive to small changes in acidity and alkalinity.

What is the pH scale range?

0 to 14.

What determines the pH of a solution?

Primarily the number of hydrogen ions (H+) and hydroxide ions (OH-) in the solution.

What is an acidic solution?

A solution with a pH below 7.0 that forms hydrogen ions (H+).

What is the pH range of an acidic solution?

Below 7.0.

What are examples of acidic substances?

Lemons (pH 2), tomatoes (pH 4), and milk (pH 5).

What is a neutral solution?

A solution with a pH of exactly 7.0.

What is an example of a neutral solution?

Distilled water.

What is a basic or alkaline solution?

A solution with a pH above 7.0 that forms hydroxide ions (OH-).

What is the pH range of a basic solution?

Above 7.0.

What are examples of basic substances?

Eggs (pH 8) and drain cleaner (pH 13).

What is the neutral pH?

7.0.

What is the average pH range of blood?

7.35 to 7.45.

Is blood acidic, neutral, or basic?

Slightly basic (alkaline).

What is water known as?

The universal solvent.

Why is water called the universal solvent?

It dissolves many substances and provides an excellent suspension medium for transporting nutrients and wastes.

What is a solvent?

A liquid or gas in which another material is dissolved.

What is a solute?

The atom, molecule, or compound that is dissolved in a solvent.

What is a solution?

A combination of a solvent and a solute.

What is the role of water in transportation?

It helps transport molecules, nutrients, and wastes throughout the body through circulation.

How does water function as a lubricant?

It reduces friction and helps hold substances together in different areas of the body.

What body fluids contain water?

Blood plasma, mucus, saliva, bile, amniotic fluid, synovial fluid, and serous fluid.

How does water help regulate body temperature?

It absorbs and releases heat very slowly.

Why is water important for digestion?

It helps break larger molecules into smaller molecules.

Why is water important for waste removal?

It helps remove waste products from the body.

What are inorganic compounds?

Compounds that generally lack carbon atoms. If they contain carbon, they do not contain both carbon and hydrogen.

Are inorganic compounds important to the body?

Yes, they are vital for normal physiological functioning.

How are many inorganic molecules bonded?

Ionically bonded.

What are examples of inorganic compounds?

Carbon dioxide, water, and oxygen.

What are organic compounds?

Compounds that contain both carbon and hydrogen atoms.

How are organic compounds primarily bonded?

Almost exclusively by covalent bonds.

Why can carbon form large organic molecules?

Carbon atoms can bond together to form long chains and large molecules.

What are the four major organic compounds?

Carbohydrates, lipids, proteins, and nucleic acids.

What are carbohydrates also known as?

Sugars and starches.

What is the hydrogen-to-oxygen ratio in carbohydrates?

2:1.

What is the general formula for carbohydrates?

(CH2O)n.

What is one structural function of carbohydrates?

They provide structural units found in DNA and cell membranes.

What is the main function of carbohydrates?

They provide the body's major energy source.

How many kilocalories does one gram of carbohydrates provide according to the notes?

4.5 Kcalories.

What is the only energy source for brain and nerve cells according to the notes?

Carbohydrates.