Water and Carbon FINAL

Are different ions.

Atoms with the same number of protons but with different electrical charges _____.

Potential

Chemical energy is a form of _____ energy.

Four...hydrogen

Each water molecule is joined to _____ other water molecules by ____ bonds.

10

Fluorine's atomic number is 9 and its atomic mass is 19. How many neutrons does fluorine have?

It has one more proton than it does electrons.

If an atom has a charge of +1, which of the following must be true?

Ionic

In salt, what is the nature of the bond between sodium and chlorine?

Cellular respiration

In your body, what process converts the chemical energy found in glucose into the chemical energy found in ATP?

6

What is the atomic number of an atom that has 6 protons, 6 neutrons, and 6 electrons?

Energy cannot be created or destroyed but can be converted from one form to another.

"Conservation of energy" refers to the fact that _____.

Must proceed without an input of external energy.

A chemical reaction that proceeds spontaneously _____.

Molecule

A(n) _____ refers to two or more atoms held together by covalent bonds.

An attraction between ions of opposite charge.

An ionic bond involves _____.

5

An uncharged atom of boron has an atomic number of 5 and an atomic mass of 11. How many protons does boron have?

Almost empty; cations.

Elements found on the left side of the periodic table contain outer shells that are _____; these elements tend to form _____ in solution.

+1

Nitrogen (N) normally forms only three covalent bonds because it has a valence of five. However, ammonium has four covalent bonds, each to a different hydrogen (H) atom (H has a valence of one). Make a sketch of this molecule. Count the number of electrons in your sketch. Compare this number to the number of valence electrons in one N and four H's. What do you predict to be the charge on this molecule?

The nucleus of silicon is probably too big to form long chains of Si-Si molecules (analogous to long chains of carbon molecules).

Silicon's atomic number is 14; in the periodic table it is directly beneath carbon. Silicon is abundant in the Earth's crust, yet, unlike C, N, O, and H, silicon is not a common element in organisms. What about the atomic structure of silicon probably accounts for this?

2

The innermost electron shell of an atom can hold up to _____ electrons.

Hydrogen bonds.

The sole of a gecko's foot is covered with millions and millions of small, dry hairs that make direct contact with surfaces, and allow geckos to walk up walls and dangle from the ceiling. Experiments showed that the hairs stick well to strongly hydrophobic, strongly hydrophilic, and electrically neutral surfaces and that covalent bonds were not involved. What noncovalent bond is probably involved in the foot adhering to a surface?

Electronegativity

The tendency of an atom to pull electrons toward itself is referred to as its _____.

Polar

The unequal sharing of electrons within a water molecule makes the water molecule _____.

The number of electrons in the outermost electron shell.

What determines the types of chemical reactions that an atom participates in?

269

What is the mass number of an ion with 109 electrons, 159 neutrons, and a +1 charge?

C3H7OH and C2H5COOH are polar molecules.

Which of the following molecules is polar?

Heat, carbon dioxide, and water.

Which of these are by-products of cellular respiration?

A space station orbiting Earth

Which of these is exhibiting kinetic energy?

These atoms are isotopes.

Which of these refers to atoms with the same atomic number but different atomic masses?

The number of protons is equal to the number of electrons.

Which of these relationships is true of an uncharged atom?

Electrons in CH4 and O2 have relatively high P.E; electrons in CO2 and H2O have relatively low P.E.

Which statement most accurately describes the relative potential energies (P.E.) of the electrons in the following molecules: CH4, O2, CO2, and H2O?