Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology > Water > Flashcards

Water Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

Shape and structure of water molecule

A

Shaped like wide V
Two hydrogen atoms joined to an oxygen atoms by single covalent bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Water molecule’s polarity

A

water is a polar molecule because oxygen is more electronegative than hydrogen so the shared pair of electrons pair spend more time near oxygen forming polar covalent bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Overall charge of water molecule

A

Oxygen contains two regions of partial negative charge and hydrogen has a region of partial positive charge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Which type of bond is held two water molecules together?

A

Hydrogen bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Six properties of water

A

1.Polarity
2.Excellent solvent
3.High heat capacity
4.Cohesion(high surface tension)
5.Adhesion
6.Low density when frozen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How water can be excellent solvent?

A

As water molecule is polar molecule,it can dissolve poler molecules and ions due to its ability to form ion-dipole and dipole-dipole interactions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is cohesion?

A

Attraction between water molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is adhesion?

A

Attraction between water molecules and other substances

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is surface tension?

A

A measure of how difficult it is to stretch or break the surface of a liquid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Why water molecules have high surface tension?

A

At the interface between water and air,water molecules are hydrogen-bonded to one another to water molecules below but not to the above air

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is kinetic energy?

A

The energy of motion

The faster a molecule moves,the greater its kinetic energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is thermal energy?

A

The kinetic energy associated with random movements of atoms and molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is difference between thermal energy and temperature?

A

Thermal energy of a body of matter is the total kinetic energy that depends on matter’s volume

Temperature is the average kinetic energy of molecules in body without the volume of the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What will happen when two objects with the different temperature are brought together?

A

Thermal energy passes from warmer objects to cooler object until the two are at the same temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is heat?

A

Thermal energy in transfer from one body of matter to another

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Units of heat

A

Calorie(cal)-amount of heat it takes to rise the temperature of 1g of water by 1 C
Kilocalorie(kcal)-1000cal-amount of heat required to raise the temperature of 1kg of water by 1•C
Joule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Specific heat

A

The amount of heat that must be absorbed or lost for 1g of substance to change its temperature by 1•C

A measure of how well a substance resists changing its temperature when it absorbs or releases heat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Water’s specific heat

A

1cal/(g •C) i.e.1 cal of heat is required for 1g of water to change its temperature by 1•C

water resists changing its temperature when it absorbs or releases heat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Water’s high specific energy compared to ethanol

A

Water-1cal/g•C
Ethanol-0.6cal/g•C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is heat of vaporization?

A

The quantity of heat of a liquid must absorb for 1 g of liquid to be converted from liquid to gaseous state

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Do water have high heat vaporization?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Density of ice vs liquid water

A

Ice has lower density than liquid water because of crystalline lattice structure of ice

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is water density at 4•C and above?

A

At 4•C,like other liquids water expands as it warms and water contracts as it cools

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Water density at below 4•C-0•C

A

Water begins to freeze because more and more of its molecules are moving too slowly

At 0•C,the molecules is locked into crystalline lattice structure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what is solvent?

A

Dissolving agent of a solution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is solute?

A

The substance that is dissolved in solution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is solution?

A

A liquid that is completely homogeneous mixture of two or more substances

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is aqueous solution?

A

The solute is dissolved in water

water is the solvent in aqueous solution

29
Q

Which solutes can water dissolve?

A

Ionic molecules and polar molecules

30
Q

Hydrophilic molecules

A

Molecules that have affinity for water (ionic and polar molecules)

water-loving molecules

31
Q

All hydrophilic molecules are dissolved in water.True or false?

A

False,substances can be hydrophilic without actually dissolving

Eg.cotton

32
Q

Hydrophobic molecules

A

Substances that do not have an affinity for water (nonionic and non-polar molecules)

water-hating molecules

33
Q

What is molarity?

A

Molarity is the unit of concentration

The number of moles of solute per liter of solution

34
Q

What is mole?

A

A mole is a certain number of molecules of a substance.

35
Q

What is molecular mass?

A

The mass of a mole of substance in grams

36
Q

Water dissociation

A

When two water molecules are connected by a hydrogen bond ,hydrogen ions(H+) is transferred to one molecule to another forming Hydronium ions(H3O+) and the molecule that lost hydrogen ion becomes hydroxide ion(OH-)

It is the reversible reaction and reaches at a state of equilibrium

37
Q

What is the concentration of H+ and OH- in pure water?

A

same concentrations

38
Q

What is acid?

A

A substance that increases the hydrogen ion concentration of a solution

HCl——->H+ +Cl-

39
Q

What is base?

A

a substance that reduces the concentration of H+ ion

Some bases reduce H+ conc directly by accepting hydrogen ions and
other bases reduce reduce H+conc indirectly by dissociating to form OH- ions

40
Q

What is acidic solution?

A

Solution with higher concentration of H+ ions than OH- ions

acidic solution have pH value of less than 7

41
Q

What is basic solution?

A

A solution with higher concentration of OH- ions than H+ions

basic solutions have pH value of greater than 7

42
Q

How strong acid and strong base dissociate in water?

A

Completely dissociate

Eg.HCl and NaOH

43
Q

What is weak acid and weak base?

A

The substance that dissociates partially in water

44
Q

In which temperature,the product of [H+][OH-] concentration is constant?

A

25 degree Celcius

45
Q

In 25 degree Celcius,the product of [H+][OH-] concentration is constant.What is tha value of this constant?

A

[H+][OH-]=10 *-14

So [H+]=10* -7 and [OH-]=10* -7

46
Q

When enough acid is added to the solution to increase [H+] to 10*-5M ,what is [OH-] value?

A

10* -9 M

47
Q

When enough base is added to the solution to increase [OH-] to 10*-4M ,what is [H+] value?

A

10* -10 M

48
Q

pH and [H+] relation

A

pH=-log[H+]

pH decreases as H+ concentration increases

49
Q

pH 1 example

A

Battery acid

50
Q

pH 2 example

A

Gastric juice(HCl in stomach)
Lemon juice

51
Q

pH 3 example

A

Vinegar
Wine
Cola

52
Q

pH 4 and 5 example

A

Tomato juice
Beer
Black coffee

53
Q

pH 5.5 example

A

rain water

54
Q

pH 6 example

A

Urine

55
Q

pH 7 example

A

Saliva
Pure Water
Human blood
Tears

56
Q

pH 8 example

A

seawater
inside small intestine

57
Q

pH 10.5 example

A

Milk of magnesia

58
Q

pH 11.5 example

A

Household ammonia

59
Q

pH 13 example

A

Household bleach

60
Q

pH 13-14 example

A

Oven cleaner

61
Q

pH value of blood

A

7.4

62
Q

How strong acid effect on pH value of pure water?

A

if 0.01 mol of strong acid is added to 1L of pure water,pH drops from 7.0 to 2.0

63
Q

If 0.01mol of strong acid is added to 1L of blood,how the pH value change?

A

pH value decrease only 7.4 to 7.3

64
Q

Why does tha addition of strong acid of acid have so much less effect on pH of blood than it does on pH of pure water?

A

The presence of buffers in biological fluids to maintain constant pH despite the addition of acid or bases

65
Q

What is buffer?

A

a substance that minimizes changes in the concentration of H+ and OH- in a solution

Most buffer solutions are weak acid and its corresponding base,which combine reversibly with H+ ions
Eg.Carbonic acid H2CO3
Acetic acid CH3COOH

66
Q

How carbonic acid dissociate as buffer solution?

A

Carbonic acid dissociates into a bicarbonate ions(HCO3-) and hydrogen ions(H+)

The reaction is reversible and is in equilibrium state

67
Q

What will happen if the H+ concentration in blood begins to fall?

A

when [H+] fall in blood, pH of blood will rises

So more carbonic acid dissociates and replenishes H+ ions

68
Q

What will happen if the H+ concentration in blood begins to rise?

A

when [H+] rise tha pH of the blood drops

So HCO3- and H+ ions will react to form more carbonic acid(H2CO3)

69
Q

Is that correct most buffers are acid-base pairs?

A

Yes

Biology (16 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions