Exam 1 Flashcards
(121 cards)
Molecule:
A group of atoms held together by bonds
covalent bond:
Single:
Double:
when atoms share electrons, a strong bond is made.
Single Bond: two electrons between 2 atoms
Double Bond: 2 pairs of electrons and 2 pairs of atoms
Ionic Bonds: does it dissolve in water?
forms in the transfer of an electron to another atom–> generated two oppositely charged ions attract each other
yes
Hydrogen Bond:
Important in bonding molecules together–> attraction between polar molecules in which hydrogen is bound to a larger atom, such as oxygen or nitrogen. Hydrogen bonds form an attraction between the positive and negative poles of charged atoms
Solute:
the substance being dissolved (ex: salt) molecule must have a charge (polar, or hydrophilic)
Solvent:
dissolving substance (ex: water)
Rank these terms from smallest to largest: compound, element, molecule, subatomic particle.
element–> Molecule–> compound–> Subatomic Particle
What is the function of a chemical bond? Hypothesize how bonding could be helpful to an organism?
Chemical bonds function are to hold together molecules and create temporary connections essential to life.—> can be used to fuel the bodies activities
Is the hydrogen bond stronger or weaker than covalent and ionic?
hydrogen bonds are weaker than both covalent and ionic compounds — they constantly are breaking and re forming.
What is one example of how hydrogen bonds are used in living things?
Hydrogen bond makes water cohesive, and is what allows certain animals to float on the water. Surface tension
What chemical properties make water polar?
the bent shape- it looks like a v and on one end there is a negitive charge from o2 and a positive charge from the 2 positive hydrogen molecules
How do these chemical properties help plants get water in their leaves? What is this process called?
Cohesion: Hydrogens stick together which allows them to be pulled up through the roots and up into the tree.
Why is water a good solvent?
Water molecules carry a charge- for example when waters negative charge meets that of a positively charged sodium molecule—> ionic bonds holding them together are broken.
Use the terms solute and solvent in a sentence.
A solvent is the liquid that is doing the dissolving. For example, water is a solvent. A solute is the substance that is being dissolved. Something like table salt is an example of a solute.
How are these terms related? Soluble, insoluble, nonpolar, polar, hydrophobic, hydrophilic
they all have to do with things either being able to dissolve, or not dissolve in water
Which property of water helps with heat loss from large bodies of water?
Large heat capacity
high heat capacity
Which subatomic particle determines the bond type?
=
an atoms electrons determine whether and how the atom will bond with other atoms
Lipid:
molecules that include fats, oils and some steroids. – almost all do not dissolve in water
phospholipid
tightly packed lipid molecules that create a layer surrounding the cell. – layer prevents leakage of fluid form cell
hydrophobic
Does not like water
Cell
the most basic unit in any organism, the smallest unit of life. function independently and perform all necessary functions
Plasma membrane
membrane that encompasses the cell
What are phospholipids used for?
Form the membrane that enclose cells.
What is unique about the structure of the phospholipid?
Phospholipids have a polar head, and a non polar tail- creates phospholipid bilayer