Which of the following statements is true?
The energy of electrons decreases with increasing distance
Electrons removed from atoms always increase the stability
Electrons circle the nucleus like Earth around the Sun
Valence electrons are in the outermost shell
Hydrogen bonds occur between hydrogen in one polar molecule and _____ in another polar molecule. I. Oxygen II. Fluorine III. Nitrogen
III only
I, II, and III
I and II only
II only
The reactant in a redox reaction that readily donates electrons is called a/an:
reducing agent
dehydrogenase
coenzyme
redox agent
All of the following statements are true, EXCEPT _____.
mammals store carbohydrates in the form of glycogen
pasta and cereals are good sources of carbohydrates
sugars are found only in plants
starch is composed of amylopectin and amylose
A polar molecule, such as the one involved in a hydrogen bond, is sometimes called _____.
a covalent bond
a dipole
simply, hydrogen
a tripole
Carlos just finished an exhausting workout. Which of the following carbohydrates can be readily used by his body as a source of fuel?
Dietary fiber
Any kind of polysaccharide.
Cellulose
Glucose
Proteins are biological molecules made of _____.
sugars
glycerol
amino acids
nucleotides
What does the atomic number represent?
total number of electrons and protons combined
number of protons
total number of protons and neutrons
number of neutrons
A hydrogen bond is _____.
a paramolecular force
a perimolecular force
an intermolecular force
an intramolecular force
Why is solid water (ice) less dense than liquid water?
It is actually more dense.
Liquid water does not form hydrogen bonds.
Hydrogen bonds are not able to be formed.
The hydrogen bonds between water molecules are spaced out.
Which of the following roles do lipids NOT play in our bodies?
Store energy
Make up part of our cell membranes
Act as hormones
Generate heat
Which of the following properties helps explain why a city near the Pacific Ocean experiences less dramatic changes in temperature during the day compared to a city farther inland?
Water has a high specific heat.
Water has high surface tension.
Water has a low specific heat.
Water forms covalent bonds
A redox reaction can easily be explained as:
forming a bond by sharing electrons
an attraction between opposite charges
transferring electrons between reactants
the breakdown of glucose in cells
If Argon is a noble gas and its atomic number is 18, how many electrons can be found in the valence level?
6
18
8
36
Lactose is composed of a glucose molecule and a galactose molecule, therefore, lactose is classified as a _____.
monosaccharide
disaccharide
trisaccharide
polysaccharide
What atoms are connected by a peptide bond?
Amine nitrogen and another amine nitrogen
Carbonyl carbon and carbonyl oxygen
Carbonyl carbon and amino group nitrogen
Side chain groups
What is the maximum number of electrons that can occupy the 2s orbital?
2
3
8
6
In covalently bonded molecules, oxidation and reduction are determined by:
enzymes and coenzymes
reactants that are broken down
products that are synthesized
uneven sharing of electrons
Why does soap remove grease from pans when we wash dishes?
The whole soap molecule is non-polar, so it breaks apart fat
Part of the soap is polar and part is non-polar
Soap sends a chemical message to fats to break up fat blobs
Soap molecules react with fats to break up fat blobs.
Particles that are found in the atomic nucleus are:
Protons and neutrons
Protons, neutrons and electrons
Neutrons and electrons
Protons and electrons
What is the definition of a chemical?
A material containing ionic bonds only
two or more molecules connected together by chemical bonds
A material containing only non-metals
Two or more atoms connected together by chemical bonds
Which of the following is NOT a type of chemical bond?
Covalent bond
Ionic bond
Polar covalent bond
Polar ionic bond
When a protein makes it easier for a biological reaction to happen, it is acting as _____.
a transporter
a messenger
an enzyme
a structural protein
All of the following statements are true about lipids, EXCEPT that _____.
all lipids are fats
lipids are good at storing energy
lipids are biological molecules that are insoluble in water
steroid hormones like testosterone are lipids
Water's ability to move against gravity in a narrow space, such as a tube, is called:
Cohesion.
Capillary action.
Osmosis.
Hydrogen bonding.
Proteins in our skin, hair, and nails are called what?
Storage proteins
Regulatory proteins
Transport proteins
Structural proteins
If only one type of atom makes up a substance, what can you call this substance?
an element
a proton
a neutron
a compound
Which of the following type of bond normally forms between two non-metal atoms?
Metallic
Ionic
Covalent
Plastic
Which set of functional groups is always found in sugars?
Amines and alcohols.
Ethers and carboxylic acids.
Hydroxyl groups and ethers.
Ethers and amines.