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Flashcards in Atoms and reactions Deck (36)
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1

What is an isotope?

Atoms of the same element with different numbers of neutrons but the same number of protons and electrons and different masses

2

Relative isotopic mass

Mass of an isotope compared with 1/12th the mass of carbon-12

3

Relative atomic mass

Weighted mean mass of one atom of an element compared with 1/12th the mass of carbon-12

4

What is the purpose of mass spectrometry?

To determine relative isotopic masses and relative abundances of the isotope.
OR
Calculation of the relative atomic mass of an element from the relative abundances of its isotopes.

5

Charge of a nitrate ion

NO3 (1-)

6

Charge of a carbonate ion

CO3 (2-)

7

Charge of a sulphate ion

SO4 (2-)

8

Charge of a hydroxide ion

OH (1-)

9

Charge of an ammonium ion

NH4 (1+)

10

Charge of a zinc ion

Zn (2+)

11

Charge of a silver ion

Ag (1+)

12

What are spectator ions?

Ions present in a reaction mixture but do not participate in the reaction. They therefore have the same charge, formula and state and are present in the same quantity on each side of the equation.

13

What is a mole?

Unit for the amount of a substance.

14

What is Avogadro's constant?

The number of particles per mole of a substance- 6.022x10^23.

15

Define empirical formula

The simplest whole number ratio of atoms of each element present in a compound.

16

Define molecular formula

The number and type of atoms of each element in a molecule.

17

Define anhydrous

Containing no water

18

Define hydrated

Containing water

19

Define water of crystallization

When water molecules form an essential part of the crystal structure of some compounds

20

Volume of one mole of any gas

24dm^3

21

Volume of gas equation

Volume= Moles x 24(000)

22

Ideal gas equation

pV= nRT
p- pressure (Pascals)
V- volume (m^3) 1m^3= 1000dm^3
n- number of moles
R-8.314 (J/K/mol)
T-temperature (Kelvin)

23

1atm

101325Pa

24

1 bar

100kPa= 100,000Pa

25

Define percentage yield

Percentage ratio of actual yield to the theoretical yield:
Experimental yield/Theoretical yield

26

Define atom economy.
What is the equation for atom economy?

A measure of the amount of starting materials that become useful products:
Mass of desired useful product/Total mass of all products

27

The higher the atom economy...

...the less waste is produced, making the process more economic and sustainable.

28

4 common acids

HCl, H2SO4, HNO3, CH3COOH

29

3 common alkalis

NaOH, KOH, NH3

30

Define acid

A substance which releases H+ ions in aqueous solution; proton donors.

31

Define base
What kinds of molecules can these be?

A substance which receives protons; a proton acceptor: metal oxides, metal hydroxides and ammonia

32

Define alkali

A soluble base which releases OH- ions in aqueous solution

33

Define salt

Any substance formed from the reaction between an acid and either a base, alkali or carbonate. The H+ion of the acid is replaced by a metal ion or NH4+

34

Define strong acids and weak acids

A strong acid is one that ionises fully in aqueous solution.
A weak acid is one that only partially dissociates in aqueous solution. Weak acids have a higher pH.

35

Define neutralisation reactions

Reactions in which acids and alkalis react quantitatively to form a salt, so that there are no H+ or OH- ions present in the product solution. Water is formed from these ions.

36

What is titration?
Briefly describe the process.

A technique where a solution of known concentration (Standard solution) is used to determine the concentration of another solution. The titrant is typically added via burette to a known quantity of the analyte until the reaction is complete often using an indicator to show this .