Chp 2 Chemistry Flashcards
Na
Both living and nonliving things are composed of _____ consisting of ______
Matter
Elementos
Most significant elements found in living organisms (6)
Carbon, hydrogen, nitrógen, oxygen, phosphorus, sulfur
Elements are I’D by a unique ______ such as Na for sodium.
Atomic Symbol
What are the charge of the following subatomic particles?
Protons
Neutrons
Electrons
Positive
Neutral
Negative
What determines the Mass Number of an atom?
Protons and Neutrons
What is the atomic number composed of?
Protons y Electrons
What is an atom of a single element that differ in number of neutrons?
Isotope
What makes up the atomic mass?
The average of naturally occurring isotopes
The number of electrons in the ______ determine the reactivity of an atom
Valence Shell
What does the octet rule state?
Atoms react with one another to have 8 electrons in their valance shell.
_______ and ______ are formed when elements associate with each other.
Compounds and Molecules
Atomic number
Number of protons in the nucleus, determines chemical properties of an element and place on the periodic table
Mass number
Protons and neutrons
Which term refers to the average mass for all the isotopes of an atom
Atomic mass
Which substances dissociate in water, releasing hydrogen ions H+
Acids
Which substance either take up hydrogen ions H+ o release Hydroxide ions OH-
Bases
Most significant elements found in living things
CHNOPS
Carbon, Hydrogen, Nitrogen, Oxygen, Phosphorus, Sulfur
Atomic mass
Average of naturally occurring isotopes
_____ are formed when atoms lose or gain 1 or more electrons
Ion
If a molecule forms a polar covalent bond, the more _____ atom carries a slightly negative charge.
Electronegative
The polarity of water molecules forms ______ between the water molecules.
Hydrogen bonds
A hydrogen bond is a weak attraction between a slightly _____ hydrogen atom and a slightly ______ oxygen o nitrogen atom
Positive/ Negative
5 properties of water
High heat capacity High heat evaporation Solvent Cohesion y Adhesion Less dense when frozen
Ph scale measures the concentration of _______ ions.
Hydrogen
_____ Release hydrogen ions in water
Acids
Bases either release ______ ions o take up ______ ions
Hydroxide/ Hydrogen
Example of isotopes:
Carbon 12,13,14
When an atom gains an electron it is called an?
Anion
When an atom loses an electron it is called a :
Cation
