2.1 Atoms and reactions Flashcards
What is an isotope?
atoms of the same element with different numbers of neutrons and different masses
What is relative isotopic mass?
mass of an atom of an element compared with the mass of 1/12th of an atom of carbon-12
Formula with moles, mass, molar mass
moles = mass/ molar mass
What is the name of NO3-
nitrate ion
What is the name of NH4+
ammonium ion
What is the name of OH-
hydroxide ion
What is the name of SO4 2-
sulfate ion
What is the atomic number
number of protons (= electrons)
Name the 4 common acids
HCL - hydrochloric acid
H2SO4 - sulfuric acid
HNO3 - nitric acid
CH3COOH - ethanoic acid
Definition of ‘amount of substance’
the quantity whose unit is the mole
What does it mean if a substance is ‘anhydrous’?
a substance that contains no water molecules
What are the benefits of maximizing atom economy?
-more sustainable - fewer raw materials used
-minimizes chemical waste
-maximizes efficiency
-less money spent on separation process
What is the ideal gas equation?
pV=nRT
p - pressure (Pa)
V - volume (m3)
n - moles
R - ideal gas constant (8.314)
T - temperature (K)
Neutralization of acids equation
acid + base –> salt + water
How does neutralization make water?
a bade readily accepts H+ ions from the acid
e.g. OH- accept H+ to form H2O
Describe oxidation and reduction in terms of electron transfer
oxidation - loss of electrons
reduction - gain of electrons
How to calculate percentage yield?
actual amount (mol) / theoretical amount (mol)
x100
What is a strong acid?
acids that fully dissociate - release all their H+ ions
What is the value of avogadros constant?
6.02 x 10^23
What is ‘water of crystallisation’?
water molecules that form an essential part of the crystalline structure of a compound
What is a weak acid?
acids that partially dissociate in water - release some of its H+ ions
What is a base? and give examples
bases neutralise acids
e.g. metal oxides, metal hydroxides, ammonia
What is a hydrated substance?
a crystalline substance containing water
What is a standard solution?
a solution of known concentrations
What is an acid?
substances that release H+ ions when dissolved in water
What is an alkali?
substances that release OH- ions when dissolved in water
What are the charges of a proton, neutron and electron?
+1, 0, -1
What are the relative masses of a proton, neutron and electron?
1.0
1.0
1/2000
What is the definition of relative atomic mass?
the weighted mean mass of an atom compared with 1/12th of the mass of an atom of carbon-12
What is CO3 2-
carbonate ion
What is the formula of a zinc ion?
Zn 2+
What is the formula of a silver ion?
Ag+
What is the definition of ‘empirical formula’?
the simplest whole number ratio of atoms of each element in a compound
What is the definition of ‘molecular formula’?
the number and type of atoms of each element in a molecule
How to calculate moles using concentration and volume?
moles = concentration x volume
What is the formula for atom economy?
(mr of desired product) / (mr of all products) x 100
What are the 3 common alkalis?
NaOH - sodium hydroxide
KOH - potassium hydroxide
NH3 - ammonia
