Chapter 2 Mastering A&P Homework

All salts are ions, but not all ions are salts. True or False?

True

Which of the following statements is true concerning the differences between compounds and mixtures?

Compounds are all homogeneous

Calcium's atomic number is 20. It forms ions with 18 electrons. What is the electrical charge of a calcium ion?

+2

Which of the following correctly ranks the types of chemical bonds, in order, from strongest to weakest?

Covalent, ionic, hydrogen

Nonpolar molecules are the result of unequal electron pair sharing. True or False?

False

Except for elements 1 and 2, all other elements are stable with how many electrons in their outermost (valence) energy level?

8

An atom of oxygen has an atomic number of 8 and a mass number of 18. How many of each type of subatomic particle does it contain?

8 protons, 8 electrons, and 10 neutrons.

After the transfer of the electron, sodium will form an ion with ___________.

A charge of a +1

In plasma, a typical body fluid, protein floating around would be considered to be which of the following?

A solute, specifically both a colloid and an electrolyte

What is the primary energy-transferring molecule in cells?

ATP

What is the classification of a solution with a pH of 8.3?

Alkaline solution

What is an ion?

An atom that has either gained or lost electron(s)

Which of the following best describes an isotope?

An atomic structural variation in which atoms have differing numbers of neutrons.

Smallest particle of an element that retains its properties.

Atom

Number of protons in an atom.

Atomic number

Usually, the first one or two letters of an element's name.

Atomic symbol

Which of the following is not produced through chemical bonding?

Atoms

Water is an important molecule because it ______________.

Can form hydrogen bonds

Which four elements comprise approximately 96% of our body weight?

Carbon, oxygen, hydrogen, and nitrogen

Electrically charged particle due to loss of an electron

Cation

Electrolytes are charged particles called ions that are dissolved in body fluids. Which of the following ions would be considered a major anion in the body?

Chloride

A weak base buffers an acid by completely dissociating and accepting of all the acid's H+. True or False?

False

Atomic weight is equal to the number of protons and neutrons in the nucleus. True or False?

False

In a solution, the solute is the substance present in the greatest amount. True or False?

False

What type of bond if formed between the oxygen atom of one water molecule and the hydrogen atom of another water molecule?

Hydrogen bond. (The attraction between the slightly negative oxygen atom of one molecule and the slightly positively charged hydrogen atom within a separate water molecule is the basis of hydrogen bond formation. It is a form of dipole-dipole interaction.)

Rank the chemical bonds from relatively weakest to strongest.

Hydrogen, Ionic, Covalent

Which of the following is NOT one of the three major types of chemical reactions?

Hyperbolic

Sodium has one valence electron, while chlorine has seven. What type of chemical bond is most likely to occur between sodium and chlorine?

Ionic

How do ions form ionic bonds?

Ions of opposite electrical charges are attracted to each other to balance the charges.

Which is response provides the best explanation as to why ionic compounds easily dissociate in water?

Its unusual polar arrangement allows more substances to dissolve in water than in any other chemical.

What is the difference between kinetic and potential energy?

Kinetic energy is energy in action, while potential energy is stored energy.

Combined number of protons and neutrons in an atom.

Mass number of an element

Which of the following is NOT a difference between a compound and a mixture?

Mixtures are homogeneous while compounds are heterogeneous.

Combination of two or more atoms of the same element held together by chemical bonds.

Molecule

Which of the following is NOT a subatomic particle?

Molecule

Neutral subatomic particle

Neutron

Which subatomic particles contribute to an atom's mass number but not its atomic number?

Neutrons

Atoms of oxygen have a total of 8 electrons. Are these atoms stable, and why or why not?

No, because the atoms have only 6 valence electrons, but need 8 for stability.

Which of the following is NOT a fundamental subatomic unit of an element?

Nucleus

Which of the following disinguishes hydrogen bonds from covalent bonds?

Only hydrogen bonds can form between molecules

What explains the negative charge on the oxygen atom within the water molecule?

Oxygen atoms have a stronger pull on the electrons shared within a covalent bond formed between oxygen and hydrogen.

Which of the following is NOT a compound?

Oxygen gas

A molecule of water (H2O) is formed by what type of bond?

Polar covalent bonds

Formation of hydrogen bonds requires hydrogen atoms and what else?

Polar covalent bonds

Which organic molecules form the major structural materials of the body?

Proteins

Which type(s) of subatomic particles can be located within the nucleus of an atom?

Protons and Neutrons

Which of the following is true of protein structure?

Secondary protein structures are caused by hydrogen bonding between adjacent amine and carboxyl groups.

Which of the following statements about the polarity of covalent bonds is correct?

Small elements with 6 or 7 electrons are electron-hungry and usually become electromagnetic after attracting electrons.

Cortisol is a type of lipid hormone. Which type of lipid would cortisol be classified as?

Steriod

Which of the following is a FALSE statement about carbohydrates?

The chemical composition of carbohydrates includes two oxygens and one hydrogen for every carbon present.

Which of the following is true of covalent bonds?

The electrons are shared unequally

When an ionic bond forms, which part(s) of the atoms are directly involved?

The outermost electrons

Which of the following is true?

The reactivity of an atom is based on the number of electrons in its outer valence.

Which of the following is NOT one of the three basic steps involved in enzyme activity?

The substrate absorbs chemical energy from the enzyme after binding to its active site.

Which of the following is FALSE?

The weight of matter remains constant wherever it is located.

Which of the following is true about lipids?

Triglycerides are composed of three fatty acids and one glycerol and are stable because they do not dissolve in water.

ATP is an unstable, high-energy molecule that provides body cells with a form of energy that is immediately usable. True or False?

True

The major function of DNA is to store the genetic instructions that are used during protein synthesis. True or False.

True

Which of the following is not a result of hydrogen bonds?

Two hydrogen atoms join together to form a molecule of hydrogen gas.

Which parts of atoms can interact (react) to form chemiclal bonds?

Valence electrons

Foods are broken down into their building blocks by adding water. This would be an example of which characteristic of water?

Water acts as a reactant

Water acts to dissolve molecules in the body. How does water dissolve salt (NaCl) in your mouth from a salty pretzel?

Water acts as a solvent because the partial negative charge on the oxygen in water attracts sodium, while the partial positive charge on hydrogen attracts chloride. This results in the separation of sodium from chloride, thus breaking the ionic bond.

Which of the following is NOT considered a form of matter?

X rays

Carbon atoms have vour valence electroms. Are they likley to react with other atoms, and why or why not?

Yes, because they can become more stable by doing so.

What holds the sodium and chloride ions together in a chemical bond?

an electrical attraction between opposite charges

In a covalent bond,

atoms share one or more pairs of electrons.

Covalent bonds:

involve the sharing of one to three pairs of electrons

The pH scale __________________.

is based on the concentration of hydrogen ions in a soluiton

Bonds between carbon and hydrogen atoms are generally_________.

nonpolar covalent bonds

Which pH is more acidic, a pH of 3, a pH of 7 or a pH of 9?

pH of 3