Basic Chemistry and The Human Body

Comprehensive practice flashcards covering basic chemistry, atomic structure, the periodic table, chemical bonding, pH, and physiological buffer systems based on the lecture transcript.

According to the lecture, what three subatomic particles make up the entire human body?

Protons, electrons, and neutrons

What is the elemental composition by mass of Oxygen in the human body?

65%

What is the elemental composition by mass of Carbon in the human body?

18%

What is the elemental composition by mass of Hydrogen in the human body?

10%

What is the atomic number of Nitrogen according to the elemental composition list?

$$7$$

What are the building blocks of all Matter?

Elements

What is the charge of a proton?

Positive (+)

What is the charge of an electron?

Negative (-)

What is the charge of a neutron?

No charge

How is the mass number of an atom calculated?

$$\text{mass number} = \text{protons} + \text{neutrons}$$

The atomic number of an element is determined by the number of which subatomic particle?

Protons

Usually, the number of protons in an atom is equal to the number of which other particle?

Electrons

What occurs to an atom when the number of protons is changed?

It becomes a new element

What is created when an atom has an uneven number of electrons and protons?

An Ion

What is the definition of an isotope?

Atoms of an element with a different number of neutrons

In the periodic table, what does the column number represent?

The number of electrons in the outer shell

In the periodic table, what does the row represent?

The number of shells

What is the 1st ionization energy unit used in the periodic table notes?

$$kJ/mol$$

Why do atoms try to fill vacancies in their outer shells?

To achieve greater stability

What are the three ways atoms fill their outer shells?

Sharing electrons, donating electrons, and accepting electrons

What is the Octet rule?

The principle that most outer shells hold 8 electrons

What is a Cation?

A positively charged ion that has lost an electron

What is an Anion?

A negatively charged ion that has gained an electron

Sodium ($Na$) and Chlorine ($Cl$) forming a bond is an example of what bond type?

Ionic Bond

Which bond type is characterized by the sharing of electrons?

Covalent Bond

Which types of bonds are the strongest and most common in living organisms?

Covalent Bonds

How do covalent bonds behave in water compared to ionic bonds?

They do not disassociate in water

What are the two types of covalent bonds mentioned in the notes?

Polar and Nonpolar

What is a Hydrogen bond?

A weak bond between polar covalent bound molecules containing hydrogen

What causes the attraction in a Hydrogen bond?

The positive charge of a Hydrogen atom is attracted to the negative charge of a molecule

What causes Van Der Waals interactions?

Partial charge due to the movement of electrons

What subatomic particle do neutrons decay into in radioactive isotopes?

Protons

What is the half-life of Carbon-14?

$5,730$ years

Into what element does Carbon-14 decay?

Nitrogen-14

How does carbon dating determine the age of remains?

By comparing the concentration of $C14$ in remains to $C14$ in the atmosphere

Water constantly splits and reforms into which two ions?

$H^+$ and $OH^-$

What is the definition of pH?

The measure of Hydrogen ion concentration ($H^+$)

What pH value is considered neutral?

$$7$$

What characterizes a substance with a pH less than 7?

Acidic (more $H^+$)

What characterizes a substance with a pH greater than 7?

Basic (more $OH^-$)

On the pH log scale, what does a 1 unit change represent?

A $10 \times$ change

What is the mathematical formula for pH?

$$pH = -\text{log}_{10}(H^+)$$

What is the normal pH range for the human body?

$7.2$ to $7.6$

What is the function of buffers in the body?

To keep pH stable

Which compound is vital to the human buffer system?

$$CO_2$$

What happens in the Carbonic Acid-Bicarbonate Buffer System when blood pH rises?

Carbonic acid dissociates to form bicarbonate and $H^+$

What is the chemical reaction when blood pH rises?

$$H_2CO_3 \rightarrow HCO_3^- + H^+$$

What happens in the Carbonic Acid-Bicarbonate Buffer System when blood pH drops?

Bicarbonate binds $H^+$ to form carbonic acid

What is the chemical reaction when blood pH drops?

$$HCO_3^- + H^+ \rightarrow H_2CO_3$$

According to the notes, what is the atomic weight or most stable mass number of Hydrogen?

$$1.00794$$