Compounds, molecular bonds, and chemical reactions Flashcards Preview

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Flashcards in Compounds, molecular bonds, and chemical reactions Deck (158)
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1
Q

How many electrons are shared in a triple covalent bond?

A

Six

2
Q

Where do hydrogen bonds occur?

A

Between molecules where covalently bonded hydrogen interacts with F, O, or N on another molecule

3
Q

What occurs in a substitution reaction?

A

An atom or group of atoms from one reactant is substituted for an atom or group of atoms on a second reactant molecule

4
Q

A charge attraction between positively charged metal ions and surrounding electrons is what type of bond?

A

Metallic

5
Q

What type of bond forms between a metal and a non-metal ion?

A

Ionic

6
Q

In a chemical equation, what is indicated by an arrow with a delta (Δ) above it?

A

Heated

7
Q

What is the strongest of the dipole-dipole interactions?

A

Hydrogen bonds

8
Q

Amino acids become proteins through what type of reaction?

A

Condensation reaction

9
Q

Which are stronger, ionic or covalent bonds?

A

Ionic

10
Q

Are dipole-dipole attractions intermolecuar or intramolecular forces?

A

Intermolecular forces

11
Q

What is a metallic bond?

A

A charge attraction between positively charged metal ions and surrounding electrons

12
Q

What is the purpose of VESPR (valence shell electron pair repulsion theory)?

A

It is a way to understand the three-dimensional nature of compounds

13
Q

Do polar and non-polar compounds mix?

A

No, they are hydrophilic and hydrophobic respectively

14
Q

An atom or group of atoms from one reactant being substituted for an atom or group of atoms on a second reactant molecule is what type of reaction?

A

Substitution reaction

15
Q

What type of reaction is the opposite to an elimination reaction?

A

Addition

16
Q

What occurs in an addition reaction?

A

Two or more reactants combine to form a single product

17
Q

Which has a higher boiling point, ammonia or dihydrogen sulfide? Explain the reasoning

A

Are there H bonds to F, O, or N? If yes like ammonia, the bonds between molecules will be hydrogen bonds. If there are H but not F, O, or N like in dihydrogen sulfide, the bonds will be dipole-dipole attractions. Hydrogen bonds are the strongest of the dipole-dipole bonds, therefore ammonia would have the higher boiling point

18
Q

What is indicated by three parallel lines in a Lewis dot structure?

A

Three pairs of shared electrons in a covalent bond

19
Q

Do chemical equations occur in one direction?

A

Not necessarily, as shown by the arrows in equations the reaction can be one or two directional

20
Q

Which are stronger, dipole-dipole attractions or dispersion forces?

A

Dipole-dipole attractions

21
Q

In which type of reaction can the loss or gain of hydrogen or oxygen be considered?

A

Redox reaction

22
Q

Why is sodium a soft metal?

A

It shares one valence electron

23
Q

The geometry of a molecule is determined by electron ____

A

Repulsion

24
Q

Unsaturated compounds can be produced from a saturated compound by what type of reaction?

A

Elimination reaction

25
Q

What is written first when naming ionic compounds?

A

The name of the metal

26
Q

Which type of reaction can change the shape of a single molecule?

A

Isomerisation reaction

27
Q

Are non-polar compounds hydrophilic or hydrophobic?

A

Hydrophobic

28
Q

In a chemical equation, what shows a substance to be in a liquid physical state?

A

‘𝘭’ in italics, normal font, and/or subscript

29
Q

Describe the movement of electrons in metallic bonding

A

The nuclei are bound in a sea of surrounding electrons - vacant orbitals overlap and allow electrons to flow between neighbouring atoms

30
Q

What type of bond is the sharing of electrons betweed two atoms?

A

Covalent

31
Q

How is a covalent bond between three pairs of electrons shown in Lewis dot structures?

A

Three parallel lines

32
Q

What is indicated by ‘R’ on a skeletal structure?

A

R is used to represent a side chain (there is no ‘R’ element)

33
Q

In which type of bonding are valence electrons shared between cation nuclei?

A

Metallic

34
Q

How many electrons are shared in a double covalent bond?

A

Four

35
Q

Why does carbon ‘prefer’ to make 4 single covalent bonds than any combination of single, double, and triple?

A

It is easier to share one electron than it is to share two or three at once

36
Q

What is the purpose of the arrows in chemical reactions?

A

To separate reactants an products, and to show direction of the reaction

37
Q

What is the result of shared electrons in a covalent bond?

A

Compound stability

38
Q

What occurs in metallic bonds?

A

The metal cation nuclei are bound in a sea of surrounding electrons

39
Q

Is it easy to remove or add electrons if the ion has a full valence shell?

A

No - this is why noble gases have low reactivity

40
Q

How many electrons are shared in a single covalent bond?

A

Two

41
Q

A charge attraction between positive and negative ions is what type of bond?

A

Ionic

42
Q

What are depicted in chemical equations?

A

Reactants, products, and the relative amount of both

43
Q

Connections between atoms of a compound are called ____ bonds

A

Intramolecular

44
Q

What does a plain line on a Lewis structure indicate?

A

The two atoms are planar (flat; on one plane)

45
Q

In a chemical equation, what shows a substance to be in a gaseous physical state?

A

‘𝘨’ in italics, normal font, and/or subscript

46
Q

What can be produced by chemical reactions?

A

New substances, colour changes, heat changes (not released or absorbed, 𝘤𝘩𝘢𝘯𝘨𝘦𝘥), solids to appear or disappear, gases to be formed, light or sound created

47
Q

What is a redox reaction?

A

Oxidation-reduction reaction, wherein a reactant loses electrons (oxidises) and a reactant gains electrons (reduces)

48
Q

Nucleotides become nucleic acids through what type of reaction?

A

Condensation reaction

49
Q

Two reactants coming together to form two new products, one of which is eliminated, is what type of reaction?

A

Condensation reaction

50
Q

Do hydrophilic and hydrophobic compounds mix?

A

No, they are polar and non-polar respectively

51
Q

What type of atoms do ionic bonds form between?

A

A metal and a non-metal ion

52
Q

What type of bond governs the physical properties of substances, intermolecular or intramolcular?

A

Intermolecular

53
Q

Does one reactant give one product?

A

Not necessarily, one reactant can give multiple products

54
Q

A high melting point means a high amount of energy is required to do what?

A

Break apart the bonds

55
Q

What type of force is biochemically important for non-polar molecules?

A

Van der Waal’s forces

56
Q

Give the stoichiometric ratio for the following equation.

C₃H₈ + 5O₂ → 4H₂O + 3CO₂

5 moles of O₂ are required to burn 1 mole of propane, which produces 4 moles of H₂O and 3 moles of CO₂

A

1 : 5 → 4 : 3

57
Q

Can a dipole exist within a compound?

A

Yes, dipoles can exist within a compound

58
Q

Gain of electrons results in what type of ion?

A

Anion

59
Q

What is a dipole?

A

A molecule with regions that are opposite charges

60
Q

Is melting governed by intermolecular or intramolecular bonds?

A

Intermolecular bonds

61
Q

Reactants are written on which side of a chemical equation?

A

Reactants are written on the left

62
Q

Main group elements react to achieve full outer shell valency of 8 electrons - what is this rule?

A

The octet rule

63
Q

What is represented by a dot in Lewis dot structures?

A

An electron

64
Q

Name three types of intermolecular bonds

A

Hydrogen bonds
Dipole-dipole bonds
Van der Waals forces

65
Q

Briefly explain how Van der Waal’s forces (AKA dispersion/London dispersion forces) function

A

A larger proportion of electrons occurs on one side of an atom, creating a temporary dipole. Dispersion forces exist between the positive end of one temporary dipole and the negative end of another. This state is brief and very easily broken.

66
Q

What does VESPR stand for?

A

Valence shell electron pair repulsion theory

67
Q

Polymerisation of some monomers to form polymers is what type of reaction?

A

Condensation reaction

68
Q

Are subscripts altered when balancing equations?

A

𝘕𝘰

69
Q

Do multiple reactants give multiple products?

A

Not necessarily, multiple reactants can give one product

70
Q

Which intermolecular forces are the strongest?

A

Hydrogen bonds

71
Q

Most 3D structures of what type of bond have a crystal lattice structure?

A

Ionic

72
Q

What is the term for a molecule with one +ve end and one -ve end?

A

A dipole; it is a dipolar molecule

73
Q

Why is tungsten a hard metal?

A

It shares many valence electrons, creating more attactive forces between negative and positive

74
Q

How is a covalent bond between two pairs of electrons shown in Lewis dot structures?

A

Two parallel lines

75
Q

Hydrogen bonds are the strongest of which type of interactions?

A

Dipole-dipole

76
Q

What does the mnemonic ‘oil rig’ stand for?

A

Oxidation is loss, reduction is gain

77
Q

What are the different methods of representing biomolecules?

A

Skeletal/line structure
3D structure
Ball-and-stick model
Space-filling model

78
Q

Dipole-dipole is what kind of interaction?

A

Polar electrostatic interaction

79
Q

As ionic bonds are electrostatic attractions, what is required for a stable compound?

A

All charged to be balanced; positive and negative must be equal

80
Q

What occurs in a condensation reaction?

A

Two reactants come together to form two new products, one of which is eliminated during the reaction

81
Q

What is the term used to describe the physical state of something dissolved in water?

A

Aqueous

82
Q

What does a dashed line on a Lewis structure indicate?

A

A dashed line indicates ‘inward’ direction, away from the reader

83
Q

How do electron clouds enforce bonding angles?

A

By repelling each other

84
Q

What is a dipole-dipole attraction?

A

The negative side of one dipole interacting with the positive side of another dipole

85
Q

Most 3D ionic structures will have what kind of structure?

A

Crystal lattice

86
Q

Two non-metals sharing valence electrons to complete their octets is what type of bond?

A

Covalent

87
Q

What is the name of Al₂O₃ (aluminium and oxygen)?

A

Aluminium oxide

88
Q

What is the name of KI (potassium and iodine)?

A

Potassium iodide

89
Q

Are polar compounds hydrophilic or hydrophobic?

A

Hydrophilic

90
Q

What is the name of symbols used to visualise atom valency?

A

Lewis dot structures

91
Q

The loss of electrons is what process?

A

Oxidation

92
Q

What are the steps for balancing equations?

A
  1. Write the atoms below each side of the equation (they should be the same)
  2. Write the number of atoms present next to its corresponding symbol (don’t forget the numbers out the front which are multipliers of the amount of molecules)
  3. Alter the coefficients to balance the equation (do 𝘯𝘰𝘵 alter the subscripts)
93
Q

Is surface tension governed by intermolecular or intramolecular bonds?

A

Intermolecular bonds

94
Q

Is boiling point governed by intermolecular or intramolecular bonds?

A

Intermolecular bonds

95
Q

Name the classifications of organic chemical reactions

A
Addition
Elimination
Condensation
Substitution
Isomerisation
Oxidation and reduction (redox) - subtype: combustion reaction
96
Q

What type of bond forms between two non-metals?

A

Covalent

97
Q

What separates multiple reactants or products in a chemical equation?

A

A plus (+) symbol

98
Q

What are the reactants in a combustion reaction?

A

Carbon source + O₂

99
Q

Name four physical properties of substances that are governed by intermolecular bonds

A

Boiling point, melting point, viscosity, surface tension

100
Q

What is stoichiometry?

A

The measure of elements to determine the quantitative relationship between reactants and products in a reaction.
TLDR; knowing the amount of reactants or products tells us the amount of products or reactants respectively (due to the law of conservation of matter)

101
Q

What occurs in oxidation?

A

A reactant loses electrons

102
Q

In a chemical equation, what shows a substance to be in a solid physical state?

A

‘𝘴’ in italics, normal font, and/or subscript

103
Q

What is written second when naming ionic compounds?

A

The name of the non-metal, usually the first syllable with the suffix ‘-ide’

104
Q

The gain of electrons is what process?

A

Reduction

105
Q

One mole of atoms is equal to how many atoms?

A

6.022x10²³

106
Q

Which governs how different biomolecules are able to interact with each other, intermolecular or intramolecular forces?

A

Intermolecular forces

107
Q

What is the weakest form of intermolecular force?

A

Van der Waal’s forces (AKA dispersion forces/London dispersion forces)

108
Q

Which is stronger, covalent bonds holding a molecule together or dipole-dipole forces keeping the molecules together?

A

Covalent bonds

109
Q

What type of reaction can produce unsaturated compounds from a saturated compound?

A

Elimination reactions

110
Q

Loss of electrons results in what type of ion?

A

Cation

111
Q

Two or more reactants combining to yield a single product is what type of reaction?

A

Addition reaction

112
Q

What is an advantage of an ionic bonded substanes having a crystal lattice structure?

A

The crystal lattice structure is stronger/more solid/harder than the individual elements alone

113
Q

The coefficients in a chemical equation tell us the ____ of the reaction

A

Stoichiometry

114
Q

A bond formed by the sharing of electrons between two atoms is what type of bond?

A

Covalent

115
Q

What occurs in an elimination reaction?

A

Reactant loses some atoms to form a compound with a new double bond, while those atoms form a new product/s

116
Q

What is a covalent bond?

A

A bond formed by the sharing of electrons between two atoms

117
Q

Which bond occurs between molecules where covalently bonded hydrogen interacts with F, O, or N on another molecule?

A

Hydrogen bonds

118
Q

The force of intermolecular bonds is ____ in nature

A

Electrostatic

119
Q

How many covalent bonds can carbon make?

A

Carbon has 4 valence electrons, so can make up to 4 covalent bonds

120
Q

What are the three major types of intramolecular bonds?

A

Metallic, ionic, and covalent

121
Q

Monosaccharides become polysaccharides through what type of reaction?

A

Condensation reaction

122
Q

Why are hydrogen bonds the strongest of the dipole-dipole interactions?

A

They occur between the most electronegative atoms

123
Q

What type of bond is an attration between cations and anions?

A

Ionic

124
Q

Why do chemical reactions never cause a loss or gain in matter?

A

The Law of Conservation of Matter - in any given system that is closed to the transfer of matter (in and out), the amount of matter in the system stays constant.

125
Q

Which are stronger, intramolecular or intermolecular bonds?

A

Intramolecular

126
Q

What does a solid/thick/bold line on a Lewis structure indicate?

A

A thick/bold line indicates ‘outward’ direction, towards the reader

127
Q

What is an aqueous substance?

A

Something dissolved in water

128
Q

What is an ionic bond?

A

A charge attraction between positive and negative ions

129
Q

Which governs states of matter, intermolecular or intramolecular forces?

A

Intermolecular forces

130
Q

In a chemical equation, what shows a substance to be in a aqueous physical state?

A

‘𝘢𝘲’ in italics, normal font, and/or subscript

131
Q

How are physical states shown in chemical equations?

A

𝘴 (solid), 𝘭 (liquid), 𝘨 (gas), 𝘢𝘲 (aqueous)

132
Q

A dipole that spans the whole molecule results in that molecule being referred to as a ____ molecule

A

Polar

133
Q

What occurs in an isomerisation reaction?

A

A single molecule undergoes electron reorganisation; this is intermolecular rearrangement where transposition of double bonds or cis-trans rearrangement of double bonds occurs

134
Q

Is viscosity governed by intermolecular or intramolecular bonds?

A

Intermolecular bonds

135
Q

What is almost always required for an addition reaction?

A

One reactant to have a multi-covalent bond

136
Q

The overall polarity of molecules is due to what?

A

Electron density

137
Q

Direct reaction of many compounds with O₂ is accompanied with what type of reaction?

A

Combustion reaction

138
Q

What is the octet rule?

A

Main group elements react to achieve full outer shell valency of 8 electrons; gain or loss of electrons occurs to ensure a valency of 8

139
Q

A bond between two carbon atoms is what type of bond?

A

Covalent

140
Q

How is a covalent bond between one pair of electrons shown in Lewis dot structures?

A

A single line

141
Q

Van der Waal’s forces are biochemically important for what substances?

A

Non-polar molecules

142
Q

The more energy that is required to break apart the bonds in a substance, the higher the ____ ____ (physical property) will be

A

Melting point

143
Q

What is never caused be chemical reactions?

A

Loss or gain in matter

144
Q

If dipoles can exist within a compound, what is true about multiple dipoles in a compound?

A

The dipoles within compounds can cancel each other out

145
Q

What metabolic process involves a set of reactions which includes electron carriers facilitating generation of ATP?

A

Complete oxidation of glucose

146
Q

What occurs in reduction?

A

A reactant gains electrons

147
Q

A reactant losing some atoms to for a compound with a few double bond while those atoms form a new compound/s is what type of reaction?

A

Elimination reaction

148
Q

The negative side of one dipole interacting with the positive side of another dipole forms what kind of attraction?

A

Dipole-dipole

149
Q

Products are written on which side of a chemical equation?

A

Products are written on the right

150
Q

What molecular mass unit is used in biochemistry?

A

Da (Daltons)

151
Q

Give an example of a molecule in which multiple dipoles cancel each other out, resulting in an overall non-polar molecule

A

Carbon dioxide

152
Q

What type of reaction can be initiated by heat or light and is actioned by enzymes?

A

Isomerisation reaction

153
Q

Electrostatic forces that keep matter together are what type of bond, intermolecular or intramolecular?

A

Intermolecular bonds

154
Q

What type of reaction is the opposite to an addition reaction?

A

Elimination

155
Q

What happens to electrons in metallic bonding?

A

The valence electrons are shared between cation nucei via overlapping orbitals

156
Q

What are the products in a combustion reaction?

A

CO₂ + H₂O + energy

157
Q

If a stick leads to an empty space in a skeletal structure, what is actually at the end?

A

A hydrogen atom

158
Q

What is indicated by two parallel lines in a Lewis dot structure?

A

Two pairs of shared electrons in a covalent bond