Chapter 2 - The Chemical Context Of Life Flashcards
What is matter ?
Anything that takes up mass and exits in many forms
What are elements ?
Any substance that can’t be broken down to other substances by chemical reactions
What are compounds ?
Substances that consist of two or more different elements
These 4 elements makes up 96% of all living matter.
Oxygen, Nitrogen, Hydrogen, and Carbon
This subatomic particle is positively charged ?
Proton
This subatomic particle is negatively charged ?
Electrons
This subatomic particle is neutrally charged ?
Neutrons
1.) ________ and 2.) __________ are densely packed in the atomic nucleus with 3.) __________ forming a cloud around the nucleus.
1.) Protons
2.) Neutrons
3.) Electrons
Every element has the same number of _________ and ___________.
Protons and electrons
Atomic number refers to the number of _____________ and is written at the bottom of the element.
Protons
Atomic Mass refers to the number of __________ + ____________ and is written at the top of the element.
Protons and Neutrons
Isotopes are different forms of the same element. Having the same protons and electrons but different __________.
neutrons
The 1st electron shell can hold up to ____ electrons.
2
The 2nd electron shell can hold up to _____ electrons. This is known as the ________.
8, Octet Rule
An atom with a complete valence shell (8) is ?
Non-reactive and will not interact with other atoms
Only atoms with incomplete valence shell (less than 8) can ?
Make chemical bonds
Covalent bonds
Share electrons by two atoms and makes a molecule
The attraction of atoms from the electrons of a covalent bond is called ____________.
ELECTRONEGATIVITY
The more electronegative an atom is the more __________ it pulls towards itself.
Electrons
Non-polar covalent bonds
Share equal parts of the electron because the electronegativity is the same
Polar covalent bonds
Do not share electrons equally or at all because one atom is more electronegative than the other.
Example : Oxygen (O) is more electronegative than Hydrogen (H) and pulls 2 H atoms towards itself making water (H2O)
Ionic Bonds
Atoms share or transfer electrons which makes an ion from an ionic bond
Positively charged ions that lose/transfer electrons are ?
Cations (+)
Negativity charged ions that gain/accept electrons are ?
Anions (-)
Hydrogen atoms bond to an electronegative atom, giving it _____________
partially charged positive areas
Hydrogen bonds are usually seen as _______ lines and bonded to oxygen with ________ lines.
Dotted, straight
