Amount of Substance formulas/definitions Flashcards Preview

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Flashcards in Amount of Substance formulas/definitions Deck (16)
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1
Q

moles=

A

mass/mr

2
Q

percentage composition=

A

Ar x no. of atoms
———————– x 100
Mr of molecule

3
Q

atom economy

A

mass of desired product
———————————– x100
mass of reactants

4
Q

percentage yield

A

actual mass
———————- x100
theoretical mass

5
Q

reasons for <100% yield

A
  • reaction doesn’t go to completion
  • side reactions
  • reversible reactions
  • loss of product during transfer
  • impure reactants
6
Q

ideal gas equation

A

pV=nRT

7
Q

units for p in ideal gas equation

A

Pa

8
Q

units for V in ideal gas equation

A

m3

9
Q

what is R?

A

gas constant - 8.31 JK-1mol-1

10
Q

units for T in ideal gas equation

A

K

11
Q

What is an ideal gas?

A
  • particles have no volume
  • no attraction/repulsion between particles
  • particles are identical and in continuous random motion
  • collisions are elastic
12
Q

concentration =

A

moles/volume

13
Q

Avogadro’s constant =

A

6.022 x 10^23

14
Q

what is empirical formula?

A

simplest whole number ratio of atoms of each element in a compound

15
Q

what is molecular formulas?

A

actual number of atoms of each element in a compound

16
Q

what is stoichiometry?

A

simplest whole number ratio in which chemical species react