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Flashcards in CALCULATIONS Deck (40)
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1
Q

define mole

A

The amount of substance in grams that has the same number of particles as there are atoms in 12 grams of carbon-12

2
Q

Define relative atomic mass

A

The average mass of one atom compared to one twelfth of the mass of one atom of carbon 12

3
Q

Define relative molecular mass

A

The average mass of a molecule compared to one twelfth of the mass of one atom of carbon 12

4
Q

What is Avogadro’s number

A

6.022 x 10 ^23

5
Q

Three mole calculations

A

Moles = mass/mr

Pressure x Volume = Moles x Constant x Temperature

Moles = concentration x volume

6
Q

What is the gas constant

A

8.31

7
Q

What are the units for the gas equation

A

Pressure : pascals

Volume : m3

Temperature : kelvin

8
Q

How do you convert volumes

A

Cm3/1000 = dm3

Cm3/1,000,000 = m3

Dm3/1000 = m3

9
Q

How do you temperature

A

C + 273 = K

10
Q

How many significant figures should things be given to?

A

Same as the data in the question unless stated otherwise

Or the smallest used in the question

11
Q

Outline the Avogadro’s constant equation

A

Number of particles = moles x Avogadro’s constant

6.022 x10^23

12
Q

What is the density equation

A

Density = mass/volume

13
Q

Define empirical formula

A

Simplest ratio of atoms of each element in the compound

14
Q

Outline the general method for calculating empire lie formula

A

1) divide each mass by atomic mass
2) Divide each answer by the smallest
(3) multiply to get whole numbers)

15
Q

Define molecular formula

A

The actual number of atoms of each element in the compound

16
Q

Outline how molecular formula is calculated from the empirical formula

A

Calculate the atomic mass

Mr/atomic mass

Convert ratios

17
Q

How do you balance an ionic equation

A

Atoms and charges must be balanced

To have the same total charge either side

18
Q

How do you convert mol dm-3 into g dm-3

A

Multiply the concentration by the substances mr

gDm-3 = mol dm-3 x Mr

19
Q

What is the percentage yield equation

A

Percentage yield =

Actual yield / theoretical yield

X100

20
Q

What is the atom economy equation

A

Percentage atom economy =

Mass of useful product / mass of all reactants

x100

21
Q

define mole

A

The amount of substance in grams that has the same number of particles as there are atoms in 12 grams of carbon-12

22
Q

Define relative atomic mass

A

The average mass of one atom compared to one twelfth of the mass of one atom of carbon 12

23
Q

Define relative molecular mass

A

The average mass of a molecule compared to one twelfth of the mass of one atom of carbon 12

24
Q

What is Avogadro’s number

A

6.022 x 10 ^23

25
Q

Three mole calculations

A

Moles = mass/mr

Pressure x Volume = Moles x Constant x Temperature

Moles = concentration x volume

26
Q

What is the gas constant

A

8.31

27
Q

What are the units for the gas equation

A

Pressure : pascals

Volume : m3

Temperature : kelvin

28
Q

How do you convert volumes

A

Cm3/1000 = dm3

Cm3/1,000,000 = m3

Dm3/1000 = m3

29
Q

How do you temperature

A

C + 273 = K

30
Q

How many significant figures should things be given to?

A

Same as the data in the question unless stated otherwise

Or the smallest used in the question

31
Q

Outline the Avogadro’s constant equation

A

Number of particles = moles x Avogadro’s constant

6.022 x10^23

32
Q

What is the density equation

A

Density = mass/volume

33
Q

Define empirical formula

A

Simplest ratio of atoms of each element in the compound

34
Q

Outline the general method for calculating empire lie formula

A

1) divide each mass by atomic mass
2) Divide each answer by the smallest
(3) multiply to get whole numbers)

35
Q

Define molecular formula

A

The actual number of atoms of each element in the compound

36
Q

Outline how molecular formula is calculated from the empirical formula

A

Calculate the atomic mass

Mr/atomic mass

Convert ratios

37
Q

How do you balance an ionic equation

A

Atoms and charges must be balanced

To have the same total charge either side

38
Q

How do you convert mol dm-3 into g dm-3

A

Multiply the concentration by the substances mr

gDm-3 = mol dm-3 x Mr

39
Q

What is the percentage yield equation

A

Percentage yield =

Actual yield / theoretical yield

X100

40
Q

What is the atom economy equation

A

Percentage atom economy =

Mass of useful product / mass of all reactants

x100