Brainscape's Knowledge GenomeTM

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


See full index

Chemistry ATAR U1 > Moles > Flashcards

Moles Flashcards

You may prefer our related Brainscape-certified flashcards:
Periodic Table flashcards Chemistry 101 flashcards AP® Chemistry flashcards Organic Chemistry 101 flashcards
1
Q

What is relative mass

A

Mass cannot be measured using standard units (Too small)

Relative masses compare mass to 1/12 mass of Carbon-12 atom (No units)

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

What is relative atomic mass

A

Relative mass of single atom (On periodic table)

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

What is relative molecular mass

A

Relative mass of molecule (Sum of relative atomic masses of molecule)

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

What is relative formula mass

A

Relative mass of formula unit of ionic / covalent network substance

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

What is a mole

A

Measure number of atoms / molecules / formula units

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

What is the value of 1 mole in particles

A

6.022 x 10^23 particles (Avogadro’s Number)

Amount of atoms in 12g of Carbon-12

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

What is the formula for amount of substance in mole

A

Amount of substance in mole = (Amount of particles of substance) / (Number of particles in 1 mole)

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

What is molar mass

A

Mass (g) of one mole of pure substance

Molar mass (g) = Relative mass (g)

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

What is formula for molar mass

A

Amount of substance in mole = (Mass of substance) / (Molar mass of substance)

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

What is percentage composition

A

Proportion by mass of different elements in compound

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

What is formula for percentage composition

A

% by mass of element in compound = (Mass of element in 1 mole of compound) / (Molar mass of compound) * 100%

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

What are chemical reactions

A

When particles collide, rearranged to form “new” substances

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

What are energy changes in chemical reactions

A

Reactions involve breaking of chemical bonds, formation of new ones

  • Breaking bonds require energy absorbed from surroundings
  • Formation releases energy to surroundings
  • Energy mostly heat, light, electricity (J, kJ, MJ)
  • Change in chemical energy (Energy stored in chemical bonds) due to reaction

– Is converted to other forms

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

What are phase changes either exothermic or endothermic

A

Liquid to gas = Endothermic, energy absorbed from surroundings

Liquid to solid = Exothermic, energy released to surroundings

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

What is the conservation of energy

A

Energy cannot be created or destroyed, only transferred or transformed

System is chemical reaction, energy absorbed / released by system

  • Absorbed / Released to surroundings (Eg. Air, Water, Container)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is exothermic reactions

A

Releases energy to surroundings

17
Q

What is properties of exothermic reactions

A

Chemical energy of products < reactants

Energy absorbed < Energy released

Lost energy released to surroundings

Feels warm (Temperature change to surroundings positive)

18
Q

What is endothermic reactions

A

Absorb energy from surroundings

19
Q

What is properties of endothermic reactions

A

Chemical energy of products > reactants

Energy absorbed > Energy released

Added energy absorbed to surroundings

Feels cold (Temperature change to surroundings negative)

20
Q

What are chemical equations of exothermic reactions

A

Energy added to products

21
Q

What are chemial equations of endothermic reactions

A

Energy added to reactants

22
Q

What is enthalpy

A

Stored chemical energy of substance (J), symbol H

23
Q

What is heat of change

A

Amount of energy absorbed / released in chemical reaction

24
Q

What is enthalpy change

A

Exchange of heat between system & surroundings

Enthalpy change = Enthalpy of products - Enthalpy of reactants

25
Q

What is enthalpy change in exothermic reactions

A

Negative

26
Q

What is enthalpy change in exothermic reactions

A

Positive

27
Q

What are enthalpy diagrams

A

Graphically show change in enthalpy as reaction proceeds

28
Q

What are bond enthalpies

A

Breaking bonds require energy = Endothermic process

Forming bonds release energy = Exothermic process

29
Q

What is activation energy

A

Energy required to break bonds so chemical reaction can start

30
Q

What are energy profile diagrams

A

Show potential energy changes during course of chemical reaction

31
Q

How should energy profile diagrams in exothermic reactions look

A

Enthalpy of products < Enthalpy of reactants

Overall energy is released

32
Q

How should energy profile diagrams in exothermic reactions look

A

Enthalpy of products > Enthalpy of reactants

Overall energy is absorbed

33
Q

What are thermochemical equations

A

Sign and numerical value for energy change in equations

Enthalpy change value for reaction quoted, accompanied by equation

  • Indicates amount, per mole, of energy released / absorbed
34
Q

What are exothermic reactions thermochemical equations

A

Enthalpy change negative

Enthalpy change treated as reactant if written in equation

35
Q

What are endothermic reactions thermochemical equations

A

Enthalpy change positve

Enthalpy change treated as product if written in equation

36
Q

What is the principle of energy changes per mole in thermochemical equations

A

Comparing enthalpy change, comparsions made “per mole” of reactants

Chemical equation re-written
- “Focus” reactant coefficient of 1

37
Q

What is the effect on enthalpy change when reversing chemical reaction

A

Changes sign, not magnitude of enthalpy change

Demonstrates law of conservation of energy, true for all reversible reactions

Chemistry ATAR U1 (5 decks)

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