BIO chap 2 yay

Arrange the following states of water in order from most dense to least dense (start with most dense at the top).

liquid solid gas

The number and configuration of ______ determines the chemical behavior of an atom.

electrons

In living organisms, almost all chemical reactions are catalyzed by protein catalysts called

enzyme

When an acid is dissolved in water, how does it change the solution's pH?

It decreases the solution's pH by releasing protons in the solution

When an acid is dissolved in water, how does it change the solution's pH?

It decreases the solution's pH by releasing protons in the solution.

The attraction of water to other polar substances is called

adhesion

If two atoms have the same number of protons in their nucleus, you can conclude for sure that they

atoms of the same element

A ______ is a substance or a mixture of substances that act to resist changes in pH

buffer

Because polar water molecules attract each other, water is said to be

cohesive

Water consists of one oxygen atom joined to two hydrogen atoms by two single, polar __________ bonds

covlent

If two atoms are joined by a polar covalent bond, the atom with the lower electronegativity will have a partial ______ charge

positive

The three main types of subatomic particles are

proton neurton electron

Atomic number refers to the number of which of the following?

protons

If two atoms belong to the same element, which of the following must be true?

same number of protons

A group of atoms held together by chemical bonds in a stable association is called which of the following?

molecule

Electrons that are farther from the nucleus always have which of the following?

more potential energy

What is the charge of a hydroxide ion?

-1

Molecules that are more polar tend to have which of the following characteristics?

A higher heat of vaporization A higher specific heat

Hydrophobic exclusion

Consider a large protein molecule that has some parts that are highly hydrophobic. When placed in a water solution, the protein folds in a globular shape, such that all the hydrophobic portions are inside the molecules, away from water. This is an example of which of the following?

Which property of water strongly affects the overall shape of many biological molecules, such as protein, and DNA?

Hydrophobic exclusion

What does it mean when we say water is adhesive?

It is attracted to other polar molecules and ions.

How is the crystal structure of salt formed?

Positively charged sodium ions are attracted to negatively charged chloride ions.

If two atoms are joined by a polar covalent bond, the shared electrons will tend to stay closer to the atom with which of the following characteristic?

The higher electronegativity

If two atoms are joined by a polar covalent bond, the shared electrons will tend to stay closer to the atom with which of the following characteristic?

higher electronegivtity

______ atoms alawys have one proton

hydrogen

The atoms in NaCl are held together by what type of bond?

ionic

molecule

is made of two or more atoms held together by chemical bonds in a stable association. The atoms may or may not belong to the same element.

Electrons that are closer to the nucleus always have which of the following?

less potential energy

The _______ of a substance is a measure of how rapidly its individual molecules are moving.

temp or heat

In a neutral atom, the number of electrons is equal to which of the following?

the atomic number

Water is cohesive. Which describes this feature of water molecules?

they are attracted to each other