Chemistry of Life Flashcards
What is an element?
The simplest form of matter with unique chemical properties
What is the atomic number of each element?
The number of protons in its nucleus
What is the periodic table?
The letter symbols of elements arranged by its atomic number
How many elements have a role in our body?
24
How much of our body weight consists of Oxygen, Carbon, Hydrogen, Nitrogen Calcium, and Phosphorus?
98.5%
How much oxygen (O) is in the body?
65%
How much carbon (C) is in the body?
18.5%
How much Hydrogen (H) is in the body?
9.5%
How much Nitrogen (N) is in the body?
3.2%
How much Calcium (Ca) is in the body?
1.5%
How much Phosphorus (P) is in the body?
1%
How much Potassium (K) is in the body?
0.4%
How much Sulfur (S) is in the body?
0.3%
How much Sodium (Na) is in the body?
0.2%
How much Chlorine (Cl) is in the body?
0.2%
How much Magnesium (Mg) is in the body?
0.1%
How many trace elements are in the body?
Less than 1%
Give examples of some elements that may have traces in the body
Boron (B), Chromium (Ce), Cobalt (Co), Copper (Cu), Fluorine (F), Iodine (I), Iron (Fe), Manganese (Mn), Molybdenum (Mo), Selenium (Se), Silicon (Si), Tin (Sn), Vanadium (V), and Zinc (Zn)
What is the nucleus?
The center an atom contains
What does the atomic number represent?
The number of protons
What is a proton?
The positive charge
What is a neutron?
The neutral charge
How do you determine the atomic mass?
It is the total number of protons plus the total number of neutrons
What is an isotope?
It is the same element based on the number of protons, but with a different number of neutrons
What is an electron?
The negative charge
How do you determine if an atom has a neutral charge?
If the number of electrons and protons are equal to each other
True or false: The electrons closer to the nucleus have higher energy
False. Electrons further from the nucleus have higher energy, interact with other atoms, and determine chemical behavior
How do you determine if an atom has a negative charge?
If the number of electrons is higher than the number of protons
How do you determine if an atom has a positive charge?
If the number of protons is higher than the number of electrons
What is the smallest quantity of an element that retains the unique properties of that element?
Atoms are the smallest particles defining an element
What is the smallest independently functioning unit of an organism?
A cell
Together, just four elements make up more than 95% of the body’s mass. These include what?
Oxygen, carbon, hydrogen, and nitrogen
On the periodic table of the elements, mercury (Hg) has an atomic number of 80 and a mass number of 200.59. It has seven stable isotopes. The most abundant of these probably have what?
More than 80 neutrons
What cannot be made in our bodies?
Elements
The difference between the mass number and the atomic number for an atom is that:
A) The mass number includes all the subatomic particles while the atomic number only includes neutrons
B) The atomic number includes all the subatomic particles while the mass number only includes neutrons
C) The mass number includes both protons and neutrons while the atomic number only includes protons
D) The mass number includes all the subatomic particles while the atomic number only includes protons
E) The atomic number includes both protons and neutrons while the mass number only includes protons
C) The mass number includes both protons and neutrons while the atomic number only includes protons
The atoms of the element calcium have an atomic number of 20. Which electron shell is its valence shell?
The fourth electron shell
The atomic number designates the number of what in the atom?
Protons. The number of protons in the atom is the atomic number.
Nitrogen has an atomic number of 7. How many electron shells does it likely have?
Two
Only one of these elements is not a common element in the human body. Which element is the one that is not abundant in our bodies?
A) Oxygen (O)
B) Hydrogen (H)
C) Carbon (C)
D) Iron (Fe)
E) Nitrogen (N)
D) Iron (Fe)
Although our bodies use iron in trace amounts, it does not make up a significant portion of our bodies.
Nitrogen atoms have an atomic number of 7. How many more electrons would a nitrogen atom need to complete its valence shell?
3
Which of these atoms is stable and unreactive?
A) Sodium (Na, atomic number 11)
B) Carbon (C, atomic number 6)
C) Argon, (Ar, atomic number 18)
D) Hydrogen (H, atomic number 1)
E) Phosphorus (P, atomic number 15)
C) Argon, (Ar, atomic number 18)
Its valence shell is full with 8 electrons so it is unreactive
H2O is an example of?
A) An isotope
B) An ion
C) A molecule
D) A molecule and a compound
D) A molecule and a compound
H2O is a molecule since it is more than one atom held together by bonds, and a compound since the atoms are not all the same element
A hydrogen bond, like those found between water molecules, will bond a hydrogen atom to what?
A) A slightly positive atom
B) An electronegative atom
C) A polar atom
D) A non-polar atom
B) An electronegative atom
Hydrogen bonding will occur between the two
Which of the following is a molecule, but not a compound?
A) H2O
B) 2H
C) H2
D) H+
C) H2
Consider an atom with 6 electrons in its valence shell. When that atom becomes an ion, it is most likely to:
A) Donate 6 electrons and become a cation
B) Accept 2 electrons and become a cation
C) Accept 2 electrons and become an anion
D) Donate 6 electrons and become an anion
E) Donate 2 electrons and become a cation
C) Accept 2 electrons and become an anion