Biology Unit 2 Test

From your knowledge about the distribution of electrons in the levels and from the atomic number (in parentheses), indicate the most likely charge on the ion when this atom forms an ion. (Remember the 2, 8, 18 level distribution.) Sodium (11)

+1

From your knowledge about the distribution of electrons in the levels and from the atomic number (in parentheses), indicate the most likely charge on the ion when this atom forms an ion. (Remember the 2, 8, 18 level distribution.) Beryllium (4)

+2

Atom

The smallest unit of an element

Compound

atoms of 2 or more elements chemically bonded together

The symbol Cl- represents a chlorine atom that has ______an electron

Gained

From your knowledge about the distribution of electrons in the levels and from the atomic number (in parentheses), indicate the most likely charge on the ion when this atom forms an ion. (Remember the 2, 8, 18 level distribution.) Chlorine (17)

-1

How many hydrogens are in 5 H2O?

10

The atomic mass of an atom with 8 electrons, 8 protons, and 9 neutrons is:

17

How many electrons can the first energy level hold?

2

If an atom has 15 electrons, how many electrons are in the n=1 energy level?

2

What is the atomic mass of an element with 18 protons, 18 electrons, and 19 neutrons?

37

How many electrons does Carbon have in its outer shell?

4

If an atom has 15 electrons, how many electrons are in the n=3 energy level?

5

How many electrons can the second energy level hold?

8

If an atom has 15 electrons, how many electrons are in the n=2 energy level?

8

ionic bond

A bond formed by the attraction between two oppositely charged atoms

covalent bond

A bond formed from the sharing of electrons

reversible reaction

A chemical reaction in which the reactants used to form the products can also be synthesized from those products

synthesis reaction

A chemical reaction when two or more units are added together to form a new compound

Decomposition

A chemical reaction where the compound is broken into its parts

Exchange reaction

A chemical reaction where the substrates trade parts.

Protein

A large chain of amino acids

pH

A measure of the hydrogen concentration of a solution

Anion

A negatively charge ion

Cation

A positively charged ion

Carbonhydrate

A sugar

A substance that releases Hydrogen ions in a solution is a(n)

Acid

A substance that releases Hydrogen ions in a solution is a(n) _______ .

Acid

Ion

An electrically charged atom or group of atoms

Inorganic

Any chemical compound not containing carbon

organic

Any chemical compound that contains carbon

Matter

Anything that has mass and takes up space

The smallest unit of an element that still retains properties of that element is a(n)

Atom

Which of the following are enzyme co-factors: Calcium Iron Vitamins Water Nonmetals Zinc

Calcium Iron Zinc

______ Is the most important element of life

Carbon

Molecule

Containing two atoms

True or False: Covalent bonds form when electrons are shared between atoms

Covalent bonds form when electrons are shared between atoms

Nucleic Acid

DNA and RNA

Identify the type of reaction CCl4 ->C + 2Cl2

Decomposition

Atoms are electrically neutral. This means that they have the same number of:

Electrons and Protons

Identify the type of reaction HCl + NaOH -> H20 + NaCl

Exchange

True or False: In a decomposition reaction the substrates trade parts

False

True or false: Lipids dissolve in water.

False

True or false: The heat of reaction is the heat needed for a chemical reaction to take place

False

True or false: When organic molecules decompose, energy is absorbed

False

true or false: Bases are compounds that produce H+ ions in solution

False

2 other names for the vertical columns in the periodic table are

Family Group

Chemical reactions inside cells are _______ than the same reactions outside cells.

Faster

Select all the compounds in the list: H2 H2O NaCl He Au

H2O NaCl

Which of the following are compounds? HCl Na NaCl N2 H2O

HCl NaCl H2O

An intramolecular force between hydrogen and oxygen, fluorine, or nitrogen is a _____ bond

Hydrogen

An intramolecular force between hydrogen and oxygen, fluorine, or nitrogen is a _____ bond.

Hydrogen

lipids

Includes fats, steroids, and phospholipids

How is RNA different from DNA?

Mostly a Single strand Sugar is Ribose Uses the base Uracil

Carbon, Hydrogen, Oxygen, and ______ make up over 95% of the human body

Nitrogen

Group 8 on the periodic table do not react with other elements and are called the:

Nobel gases

A base produces ______ ions when added to water

OH-

(Select all that apply) Proteins contain what elements: Oxygen Carbon Sulfur Nitrogen Potassium Hydrogen

Oxygen Carbon Nitrogen Hydrogen

(Select all that apply) What makes up carbohydrates Oxygen Hydrogen Nitrogen Carbon

Oxygen hydrogen carbon

When there is an unequal sharing of electrons, _____ occurs

Polarity

A substance that results from a chemical reaction is called a(n)

Product

Atomic number is determined by the number of ____ in an atom

Protons

Identify the type of reaction 2H2 + O2 -> 2H2O

Synthesis

Product

That which is produced as a result of a chemical reaction.

Valence

The number of electrons lost or gained to complete an electron's outer energy level

In DNA, adenine bonds with:

Thymine

T or F: Most of the mass of the atom is contained in the protons.

True

True or False: A catalyst for chemical reactions in biological systems is called an enzyme

True

True or False: An enzyme may react with several substrate chemicals simultaneously.

True

True or False: Enzymes act as a catalyst in chemical reactions.

True

True or False: Enzymes are necessary to act as a catalyst in chemical reactions.

True

True or False: If the outer energy level of an atom is full it does not react readily with other atoms

True

True or False: When atoms combine with other atoms or when they break apart, it is called a chemical reaction

True

True or false: Many scientists have concluded that coded information cannot arise by random undirected processes:

True

True or false: When an atom gains an electron it becomes negatively charged

True

Diatomic

Two or more atoms held together by chemical bonds

Mixture

Two or more substances mixed together

chemical equillibrium

When a reversible reaction is occurring in both directions at the same rate

Select all the parts of DNA: A sugar A phospholipid A phosphate A base A water molecule

a sugar a phosphate a base

Sickle-cell anemia is caused by an incorrect sequencing of:

amino acids

The base units of proteins are

amino acids

What are the four classes of organic molecules?

carbohydrates, lipids, proteins, nucleic acids

Inorganic molecules do not contain what element?

carbon

Starches and sugars are subdivisions of _____.

carbonhydrates

A ______ is a substance that helps a reaction take place but doesn't participate in a reaction

catalyst

Carbohydrates are the most readily available source of:

energy

When reactants break bonds, what happens?

energy released

True or false: A neutral solution contains more hydroxide ions than hydrogen ions

false

True or false: An organism can live without enzymes.

false

True or false: Inorganic compounds always contain carbon

false

true or false: Water easily dissolves organic fats

false

true or false: When an atom loses an electron it becomes negatively charged

false

Of the 3 types of lipids which two are the most similar:

fats and phospolipids

An ionic bond is formed when electrons

form ions

What are the 3 types of bonds?

ionic, covalent, hydrogen

The double helix of DNA looks similar to a:

ladder

Steroids are a type of:

lipid

Fats and steroids are subdivisions of:

lipids

In dehydration synthesis, carbohydrates:

lose a water molecule

Glucose, C6H12O6, is a:

monosaccharide

Simple sugars are called

monosaccharides

A electron has a _____ charge.

negative

The neutron has a _____charge

neutral

_____ Are the largest and most specialized molecule in a living organism.

nucleic acid

DNA and RNA are subdivisions of:

nucleic acids

The proton has a ______ charge

positive

Enzymes are a type of .

protein

Amino acids are subdivisions of:

proteins

What organic compound is an enzyme

proteins

The atomic number is the number of _____ in an atom

protons

Atomic mass is determined by _____.

protons plus neutrons

The three subatomic particles are:

protons, electrons, neutrons

A substance that enters into a chemical reaction is called a(n)

reactant

Many enzymes cannot function unless a _____ is present.

substrate

True or False: Carbon is ideally suited for covalent bonds.

true

True or false: Starch is a long chain of many glucose units.

true

true or false: Carbon is ideally suited for covalent bonds

true

true or false: DNA carries the genetic codes which determines the structure and function of an organism.

true