Fill in the Blank

1. Is this a mixture or pure substance?______________________Mixture

ClNaCl

Na

ClNa

OH

H

OHH

O O

OOO O

OH H

True or False

2. This mixture contains three compounds.________________________________False, there are only two (water & salt)

Water SaltO

H H

ClNaCl

Na

ClNa

OH

H

OHH

O O

OOO O

True or False

3. There are ten molecules in this mixture._____________

OH H

ClCl

OHH

OHH

OO

OO

O O

True

Cl

ClClCl

NH

H

H

Fill in the Blank

4. Below is a mixture of compounds and elements. What is the element?

___________________Oxygen

Oxygen

ClNa

Cl

Na

ClNaO

HH

OO

O

HH

N

HH

H

H Cl OH

HOOOOxygen

Drawing

5. How many bonds can carbon form?

Four bonds

H

H

C

H

H

5b. Draw a model of CH4.

Multiple choice

6. Which is the correct configuration for the compound C2H3OH?

CH

H OC

H

H

CH

H OC

H

H

CH

H OC

H

H

CH

H OC

H H

A B

C D

Drawing

7. Draw the structure for CH3OH?

H

H

OC

H

H

Element or Compound?

8. Indicate whether each the following substances is an element or compound.

CarbonOxygenCarbon dioxideHydrogenWater

C ElementO Element CO2 CompoundH ElementH2O Compound

Element or Compound?

9. Indicate whether each the following substances is a mixture or pure substance.

Salt Water (distilled)SeawaterSugarSalad dressing

Pure substancePure substanceMixturePure substanceMixture

Short Answer

10. Name the three particles that make up atoms and indicate their charge.

+Proton (positive)

Neutron (neutral)Electron (negative)

Multiple Choice

11. Where are electrons found in an atom?

+

A. Outside the nucleusB. Inside a protonC. Within the nucleusD. Inside a neutron

+

Multiple Choice

12. What is the mass number of the atom shown below?

+

A. 2B. 3C. 5D. 7

+

Multiple Choice

13. Which nuclei is not an isotope of the other two?

A. B. C.

++

++ +

++

Short Answer

14. What is the atomic number of the atom shown below?

+ 3

Multiple Choice

15. Which of the following is a substance formed by the chemical joining of two or more elements

in definite amounts, like H2O

A. IsotopeB. CompoundC. NucleusD. Enzyme

Multiple Choice

16. Which of the following represents the best model of a water molecule?

A. B. C. D. H HO O H O H

OHO H O

Yes or No

17. When the elements sulfur and iron are mixed and heated in a test tube, they react to form iron pyrite

(fool’s gold). Would you expect iron pyrite to retain the magnetic properties of iron or the smell of sulfur?

+

Sulfur Iron Fool’s gold

Δ

No Chemical reactions rearrange atoms into new substances with different properties.

Short Answer

18. What kind of chemical bond is shown below and how do you know?

A covalent bond.

Because the atoms are sharing the

electrons.

Short Answer

19. What type of ion is formed when an atom loses an electron?

A positive ion.+

++

+

Short Answer

20. What property of water enables water to cling to the surface of a glass or to a toothpick?

Adhesion, which means molecules of different substances are attracted to each other.

Multiple Choice

21. Which shows the correct polarity of a water molecule?

A. B. C. D.

HO

HHO

HHO

HHO

H( ) ( )

( ) ( )

Short Answer

22. What kind of mixture is paint or blood?

They are suspensions, which means they contain particles that will

eventually settle out.

Short Answer

23. In our blood, the enzyme carbonic anhydrase carries out the following reactions in order to prevent sharp, sudden changes in blood pH.

23b. What kind of system is this?

A buffer system

Carbonic anhydrase

Short Answer

24. What property of water enables insects and paper clips to float on its surface?

Cohesion, which means molecules of the same substance are attracted to each other.

Short Answer

25. What kind of chemical bond is shown below and how do you know?

An ionic bond. Because the electron was completely transferred from one atom to another rather than being shared.

This causes each atom to develop a charge (become an ion).

Short Answer

26. What kind of mixture is air or salt water?

They are solutions, because all the components are evenly distributed.

Short Answer

27. Which has the higher heat capacity—water, metal, or air?

Water does. It can absorb a lot of heat without its temperature rising too much.

Matching

28. Which pH values would you assign to the following chemicals:

• Pure water• Stomach juice• Oven cleaner • Lemon juice• Soap

71 to 213 to 142 to 39 to 10

Short Answer

29. Is this liquid acidic, basic, or neutral?How do you know?

Neutral Because there is an equal number of H+ ions and OH- ions.

Drawing

How many double bonds does carbon dioxide have?

Two double-bonds

CO O

30. Draw a model of carbon dioxide.

Drawing

31. Draw a model of acetylene (C2H2).

31b. What kind of bond is this?

A triple bond

C CH H

Short Answer32. A 3-month old sits strapped in a car seat on a

hot July day because her dad forgot she was in the car. Her body temperature climbs to 105 °F

(41 °C). What may happen to the enzymes in her body if her temperature continues to climb?

Her enzymes will unravel (denature) and she will die.

Drawing

33. Draw an amino acid.

C

HHC

H H

O

R

N Carboxyl group

Amino group

33b. Label the functional groups.

Variable group

Short Answer

34. Is this liquid acidic, basic, or neutral?34b. How do you know?

Basic Because there are more OH- ions than H+ ions in solution.

Short Answer

35. Complete the following table

Polymer MonomerProtein

Monosaccharide

NucleotidePolysaccharide

Nucleic acid

Amino acid

Short Answer

36. What reagent is used to test for proteins?

Biuret's solution

36b. What color does Biuret’s turn if proteins are present?

Lavender to purple

Short Answer

37. What is another name for monosaccharides?

Simple sugars

Short Answer

38. What reagent is used to test for simple sugars?

Benedict’s solution

38b. What color does benedict’s turn if simple sugars are present?

Yellow to orange

Polysaccharides

Starch

Disaccharides

Lactose

Short Answer

39. Give two other saccharide examples for each category

MonosaccharidesGalactose

FructoseGlucose

Sucrose

Maltose

GlycogenCellulose

Short Answer

40. In what polysaccharide do animals store their excess sugars?

Glycogen

Short Answer

Starches

41. In what polysaccharide do plants store their excess sugars?

Short Answer

42. What reagent is used to test for starches?

Lugol’s (iodine) solution

42b. What color does Lugol’s turn if starches are present?

Purple to Black

Short Answer

43. What polysaccharide gives plants their rigidity and support?

Cellulose

Short Answer

44. Complete the following table

Nucleic acid Shape FunctionSingle nucleotide Energy storage / release

Protein synthesis templateSingle-stranded helix

ATP

Storing hereditary Info

RNA

DNA Double-helix

Short Answer

45. What does the abbreviation DNA stand for?

Deoxyribonucleic acid

Short Answer

46. What does the abbreviation ATP stand for?

Adenosine triphosphate

Drawing

47. Draw and label a simple model of a triglyceride lipid.

Glycerol

3 Fatty-acid tails

Short Answer

48. Is this liquid acidic, basic, or neutral?48b. How do you know?

Acidic Because there are more H+ ions than OH- ions in solution.

Short Answer

49. What happens to the chemical bonds in a chemical reaction?

Some bonds are broken and new ones are formed.

Short Answer

50. What happens to the atoms in a chemical reaction?

Atoms are never destroyed but only rearranged into new combinations.

Short Answer

51. Identify the reactants and products in the following chemical equation:

CH4

methane

+ 2O2

oxygen

CO2

Carbon dioxide

+ 2H2Owater

Reactants Products

Drawing

52. Draw an energy releasing graph and label it using the following terms.

Products ReactantsActivation energyEn

ergy

Course of Reaction

Reactants

Products

Activation energy

Drawing

53. Show how the following reaction will change when a catalyst is added.

Activation energyReactants

Products

Ener

gy

Course of Reaction

Without catalyst

With catalyst

Short Answer

54. What is the optimum pH for each enzyme?

Enzy

me

Activ

ity

pH4 5 6 7 8 9 10 11 12 13 14

7.0 11.0

X Y

Short Answer55. One of the enzymes below functions in

humans and the other is used in an industrial plant. Which one is the human enzyme?

55b. How do you know?En

zym

e Ac

tivity

pH4 5 6 7 8 9 10 11 12 13 14

X Y

Most of the cells in the human body operate around pH 7. A pH of 11 is too extreme for the human body.

Enzyme X7.0 11.0

Short Answer56. According to the graph below, at what pH do enzymes X and Y have the same amount of

activity? How do you know?

9.0

Enzy

me

Activ

ity

pH4 5 6 7 8 9 10 11 12 13 14

X Y

A pH of 9.

Both activity curves cross

at pH 9.

Short Answer57. Study the diagram below. What is the

dark area on the brown enzyme called?Active

siteEnzyme

Short Answer58. What is the circled substance called?

Activesite

Substrate

Enzyme

Substrate

Short Answer59. What is different about the

enzyme in the yellow circle?Active

site

The substrate has bound to the

active site

Enzyme

Substrate

Short Answer

60. What is the circled complex called?

Activesite

Enzyme-substrate complex

The substrate has bound to the

active site

Enzyme

Substrate

Enzyme-substrate complex

Short Answer

61. What is happening in the circled area?

Activesite

The substrate has bound to the

active siteThe substrate

is being converted

into products

Enzyme

Substrate

Enzyme-substrate complex

The substrate is being

converted into products

Short Answer

62. What is shown in the white oval?

Products that were released

Activesite

The substrate has bound to the

active site

Enzyme

Sucrose

Enzyme-substrate complex

The substrate is being

converted into products

Short Answer63. If the substrate is sucrose, then what is the brown enzyme called?

Activesite

The substrate has bound to the

active site

Products that were released

Sucrase

Enzyme

Enzyme-substrate complex

The substrate is being

converted into products

Short Answer64. If the substrate is sucrose, then

what are the products called?Active

site

The substrate has bound to the

active site

GlucoseFructose

Sucrase

Sucrose

Enzyme

Short Answer

65. What suffix do most enzymes end with

-ase

Sucrase: Breaks down table sugar (sucrose)Carbonic anhydrase: Buffers bloodCatalase: Breaks down hydrogen peroxideAmylase: Breaks down starchesLipase: Breaks down fats

Examples:

Short Answer

66. List two proteins in the human body and their function.

keratin: Structural (makes up hair and fingernails)Amylase: Enzyme (breaks down starches)Antibodies: Defense (fights disease)Hemoglobin: Transport (carries oxygen to cells)Insulin: Hormonal (removes glucose from blood)Myosin: Motion (contracts muscle fibers)Casein: Storage (stores amino acids)

Examples:

The End