Chapter 2 Bio

This atom can form up to _____ single covalent bond(s).

4

How are cohesion and surface tension related to the chemical properties of water?

All are properties related to hydrogen bonding.

When water freezes, ice floats. Why?

In ice, the water molecules are farther apart than in liquid water.

How are ionic bonds formed?

In ionic bonds, one atom gives up an electron to a second atom.

Which of the following could be considered a chemical reaction?

Sugar and oxygen gas combine to form carbon dioxide and water.

The hydrogen bonds in liquid water are less stable than in ice. Why?

There is less movement of molecules in colder conditions

About radioactive isotopes

They can be used to diagnose diseases through imaging, such as the PET scan., They can be used to treat diseases, such as thyroid cancer., They can be used for basic research, and They can be used to generate energy.

Which of the following is NOT a true statement regarding radioactive isotopes?

They can be used to diagnose, but not to treat, certain diseases.

statement true about compounds

They contain two or more elements in a fixed ratio to each other.

Heat is _______ to break hydrogen bonds between water molecules.

absorbed

A substance that dissolves in water to produced H+ is a(n)

acid

An ionic bond is shown below. It forms as a result of _____.

an attraction between atoms that have opposite charges

A substance that dissolves in water to produced OH- is a(n)

base

A material that resists a change in pH is called a(n) _____.

buffer

How do isotopes of an element differ?

by atomic mass

The process whereby coral animals form their skeletons is called ________.

calcification

is one of the seven elements that make up a small fraction, approximately 3.7%, of living cells.

calcium

Ocean acidification is caused by ____ dissolved in water.

carbon dioxide

Attractions that hold atoms together, in general.

chemical bond

What property of water makes it move upward from the roots of plants?

cohesion and adhesion

What type of bond is joining the two hydrogen atoms?

covalent

The sharing of electrons between two atoms.

covalent bond

What is an acid?

donates hydrogen ions to solutions

A(n) _____ bond joins these two oxygen atoms.

double covalent

An atom's reactivity is determined by its

electron configuration

A phrase that applies to covalent bonding and not other kinds of bonds is

electron-sharing

An atom and an ion of the same element differ in the number of

electrons

A substance that cannot be broken down into other substances by ordinary chemical procedures is known as

element

is the transfer of thermal energy

heat

A weak bond called a _________ bond results from an attraction between a slightly positive region in a molecule and a slightly negative region in the same or a different molecule.

hydrogen

What name is given to the bond between water molecules?

hydrogen bond

In a neutral solution the concentration of _____.

hydrogen ions is equal to the concentration of hydroxide ions

Attraction between positive and negative atoms; Results from one electron being transferred from one atom to another atom.

ionic bond

Atoms or molecules with a net electric charge due to the loss or gain of one or more electrons are

ions

Water has 4 Life-Supporting properties

liquid water is cohesive, ice is less dense than liquid water, water moderates temperature, and water is the solvent of life

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

molecule

subatomic particles has appreciable mass and lacks a charge

neutrons

is one of the four elements that make up 96.3% of living cells.

nitrogen

four elements are the primary components of important biological molecules, such as proteins, carbohydrates, and lipids

nitrogen, carbon, hydrogen, and oxygen

A polar covalent bond _____.

results from the unequal sharing of electrons

Cohesion

the ability of molecules to stick to one another. As evaporation causes water loss from the leaves of the plant, this exerts a force on the remaining water in the leaf. This force is relayed through all the water molecules in the plant, culminating in its roots.

Adhesion

the clinging of one substance to another. It helps a plant by countering the pull of gravity as the water moves up from the roots.

When you add acid to a solution, _____.

the hydrogen ion concentration increases and lowers the pH

_______ is the energy associated with the random movement of molecules

thermal energy

also called micronutrients, are any chemical element required by living organisms in miniscule amounts, but cells require them to survive.

trace elements

is one of the fourteen trace elements and is a component of certain digestive enzymes and other proteins.

zinc