Anatomy Prep HW 2B
After the transfer of the electron, sodium will form an ion with __________.
a charge of +1
Which of the following is a product in the following reaction? glucose + fructose → sucrose + H2O
sucrose
Calcium's atomic number is 20. It forms ions with 18 electrons. What is the electrical charge of a calcium ion?
+2
An atom with 3 electrons in its outermost (valence) shell may have a total of ________ electrons altogether.
13
Based on the information in this figure, what is the atomic number of chlorine?
17
Atom X has 17 protons. How many electrons are in its valence shell (outermost energy level)?
7
In a covalent bond
Atoms share one or more pairs of electrons
How many hydrogen atoms will a single carbon atom bond with to form a stable molecule?
Four
How many valence shell electrons does the element carbon have?
Four
A type of bond important in tying different parts of the same molecule together into a three-dimensional structure.
Hydrogen bond
Rank the chemical bonds from relatively weakest to strongest. I. Ionic II. Covalent III. Hydrogen
III < I < II
How do ions form ionic bonds?
Ions of opposite electrical charges are attracted to each other to balance the charges.
Which of the following statements is false?
Larger particles move faster than smaller ones and thus collide more frequently and more forcefully.
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.
A bond in which electrons are shared equally.
Nonpolar covalent bond
Which of the following distinguishes 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.
A bond in which electrons are shared unequally.
Polar covalent bond
Which of the following is true of polar covalent bonds
The electrons are shared unequally
Which of the following is true?
The reactivity of an atom is based on the number of electrons in its outer valance.
What do these four elements have in common?
They all have an incomplete valence electron shell.
A chemical bond is an energy relationship between outer electrons and neighboring atoms.
True
Hydrogen bonds are too weak to bind atoms together to form molecules, but they do hold different parts of a single large molecule in a specific three-dimensional shape.
True
Which of the following is not a result of hydrogen bonds?
Two hydrogen atoms join together to form a molecule of hydrogen gas.
Carbon atoms have four valence electrons. Are they likely to react with other atoms, and why or why not?
Yes, because they can become more stable by doing so.
What is an ion?
an atom that has either gained or lost electron(s)
What holds the sodium and chloride ions together in a chemical bond?
an electrical attraction between opposite charges
Which of the following correctly ranks the types of chemical bonds, in order, from strongest to weakest?
covalent, ionic, hydrogen
What type of bond is formed between the oxygen atom of one water molecule and the hydrogen atom of another water molecule?
hydrogen bond
Covalent bonds
involve the sharing of one to three pairs of electrons.
A bond in which electrons are completely lost or gained by the atoms involved.
ionic bond
Salts are always ________.
ionic compounds
What does this figure depict?
ionization, followed by ionic bonding
Bonds between carbon and hydrogen atoms (as depicted on the right side of the figure) are generally
nonpolar covalent bonds
Lithium has an atomic number of 3. How many electrons are there in the outermost (valence) shell?
one
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
When an ionic bond forms, which part(s) of the atoms are directly involved?
the outermost electrons
A chemical reaction in which bonds are broken is usually associated with
the release of energy
What is the most significant factor in the formation of a covalent bond?
the sharing of electron pairs between two atoms
One carbon atom can combine with two oxygen atoms to form carbon dioxide. Use the diagram to predict the type of bond that would be necessary to join the oxygen's to the carbon to form a stable molecule.
two double bonds
Which parts of atoms can interact (react) to form chemical bonds?
valence electrons
The numbers listed represent the number of electrons in the first, second, and third energy levels, respectively. On this basis, which of the following is an unstable or reactive atom?
2,8,1
Which of the following is not produced through chemical bonding?
atoms
ATP → ADP + Pi is an example of a(n) ________ reaction.
decomposition
Amino acids joining together to make a peptide is a good example of a(n) ________ reaction.
synthesis
