BIOS251-EXAM 1 (WEEK 2-CHEM)
QUESTIONS WITH CORRECT ANSWERS
2025
Element - CORRECT ANSWER -
a form of matter that cannot be broken down any further by chemical reactions
Atom - CORRECT ANSWER -
the smallest particle of an element that still has the properties of that element
Protons - CORRECT ANSWER -+1 charge
Neutron - CORRECT ANSWER -neutral charge
Electrons - CORRECT ANSWER -much smaller mass than protons or neutrons; -1 charge
Atomic number - CORRECT ANSWER -number of protons in an atom
Mass number - CORRECT ANSWER -total number of protons and neutrons in an atom
Atomic weight - CORRECT ANSWER -average mass of an atom of that element
Molecules - CORRECT ANSWER -
atoms can react with either atoms of the same element or atoms of different elements to create molecul
es
-
molecules are atoms held together by electron based interactions called intermolecular bonds (electrons
interact with other atoms to form bondsgsince they are the outermost subatomic particle)
Ions - CORRECT ANSWER -
are atoms or molecules with an electrical charge which arises from an imbalance of protons and electron
s
, Electrolytes - CORRECT ANSWER -are any substance that gives off or forms ions when dissolved in water
Ionic bonding - CORRECT ANSWER -- typically btw metals and nonmetals
- form btw cations (pos charge) and anions (neggcharge)
- forms by the transfer of electrons
Covalent bonding - CORRECT ANSWER -- typically btw nonmetals
- nonmetals form covalent bonds by sharing electrons btw them, as opposed to transferring electrons
-
when one of thegatomsgin a bond has a higher affinity for electrons than the other (electronegativity), an
d a polar covalent bond is formed where electrons are shared unequally
-
when both nonmetals have similar electron affinity, a nonpolar covalent bond is formed, where the elect
rons in the covalent bond are shared equally
Metallic bonding - CORRECT ANSWER -- typically btw metals
- elements broadly classified as either metals or nonmetals; grouped on the periodic table as such
Mixture - CORRECT ANSWER -
a combination of more than one compound, physically mixed together, two types of mixtures
1. homogenous
2. heterogenous
Homogenous mixture - CORRECT ANSWER -
do not separate over time and cannot be separated by most membranes, also known as solutions
Heterogenous mixture - CORRECT ANSWER -not uniform in their composition
Solution - CORRECT ANSWER --
cannot be visually distinguished from solvent or one another; cannot be separated by a membrane; usua
lly transparent
QUESTIONS WITH CORRECT ANSWERS
2025
Element - CORRECT ANSWER -
a form of matter that cannot be broken down any further by chemical reactions
Atom - CORRECT ANSWER -
the smallest particle of an element that still has the properties of that element
Protons - CORRECT ANSWER -+1 charge
Neutron - CORRECT ANSWER -neutral charge
Electrons - CORRECT ANSWER -much smaller mass than protons or neutrons; -1 charge
Atomic number - CORRECT ANSWER -number of protons in an atom
Mass number - CORRECT ANSWER -total number of protons and neutrons in an atom
Atomic weight - CORRECT ANSWER -average mass of an atom of that element
Molecules - CORRECT ANSWER -
atoms can react with either atoms of the same element or atoms of different elements to create molecul
es
-
molecules are atoms held together by electron based interactions called intermolecular bonds (electrons
interact with other atoms to form bondsgsince they are the outermost subatomic particle)
Ions - CORRECT ANSWER -
are atoms or molecules with an electrical charge which arises from an imbalance of protons and electron
s
, Electrolytes - CORRECT ANSWER -are any substance that gives off or forms ions when dissolved in water
Ionic bonding - CORRECT ANSWER -- typically btw metals and nonmetals
- form btw cations (pos charge) and anions (neggcharge)
- forms by the transfer of electrons
Covalent bonding - CORRECT ANSWER -- typically btw nonmetals
- nonmetals form covalent bonds by sharing electrons btw them, as opposed to transferring electrons
-
when one of thegatomsgin a bond has a higher affinity for electrons than the other (electronegativity), an
d a polar covalent bond is formed where electrons are shared unequally
-
when both nonmetals have similar electron affinity, a nonpolar covalent bond is formed, where the elect
rons in the covalent bond are shared equally
Metallic bonding - CORRECT ANSWER -- typically btw metals
- elements broadly classified as either metals or nonmetals; grouped on the periodic table as such
Mixture - CORRECT ANSWER -
a combination of more than one compound, physically mixed together, two types of mixtures
1. homogenous
2. heterogenous
Homogenous mixture - CORRECT ANSWER -
do not separate over time and cannot be separated by most membranes, also known as solutions
Heterogenous mixture - CORRECT ANSWER -not uniform in their composition
Solution - CORRECT ANSWER --
cannot be visually distinguished from solvent or one another; cannot be separated by a membrane; usua
lly transparent
