Unit 1 Flashcards
What is a covalent bond?
A covalent bond is a shared pair of electrons between 2 non metal atoms.
What does an atom contain in the nucleus?
protons and neutrons
What is an isotope?
Same atomic number, different mass number
What is the shape of a molecule with the formula CH4
Tetrahedral
Is Hydrogen a diatomic molecule?
Yes-along with oxygen, nitrogen, fluorine, chlorine, bromine and iodine
What is a catalyst?
A catalyst is a substance that speeds up a chemical reaction whilst remaining unchanged
How do you find the mass number?
number of protons + number of electrons
What is the charge of an electron?
An electron is negative
What is the mass of a proton?
1 amu
How do you increase the rate of a chemical reaction?
Increase the temperature, add a catalyst, decrease surface area
What is the unit for concentration?
mol l-1 s-1
How many electrons does the second electron shell hold?
8 electrons
What shape does the third electron shell have?
Tetrahedral
Why do atoms create covalent bonds?
To create a steady electron arrangement
What number does the prefix ‘penta’ stand for?
5
Do metal ions lose or gain electron(s)?
Metal Ions loose outer electrons
T/F- Ions are charged
True
T/F- atom have unequal amounts of protons and electrons
False- atoms have equal amounts of protons and electrons
What element is Mg?
Magnesium
What is the formula for the mole?
m= GFM x n
Does covalent molecular have high or low melting/boiling points?
Low
What does delocalised mean?
Delocalised means that the outer electrons are free to move about
Do metals conduct electricity?
Yes
Do covalent solutions conduct electricity?
They do not conduct electricity as they do not have any charged particles.
What is the formula for concentration?
c= n/v
How do you work out the percentage of an element present in a compound?
% by mass= m/GFM x 100
What is the formula for sulfuric acid?
H2SO3
Do acids have a pH greater than, equal to or less than 7?
Acids have a pH less that 7
Do acids contain more or less hydrogen ions that hydroxide ions?
Acids contains more hydrogen ions than hydroxide
What happens when you add a base to an acid?
Neutralisation
What is the definition of neutralisation?
A reaction that moves the pH towards 7.
What is a soluble metal oxide?
An alkali
If an acid contains ‘sulfuric’ in its name, what does the salt name end in?
Sulfate
What is a precipitate?
An insoluble soild
What is the formula for a volumetric tritation?
C1V1/N1 = C2V2/N2
What is a spectator ion?
An ion which is present in a reaction but doesn’t take part.
What group is the halogens?
Group 7
What group is the noble gases?
Group 0/8
What group is the Alkali metals?
Group 1
What is the formula for reaction rate?
Rate= (change in) Quantity/(change in) Time
What is an indicator that a chemical reaction has taken place?
A colour change/ a gas given off/ a solid forming/ energy change
Do ionic compounds conduct?
They do not conduct because the ions are not free to move
Do metallic compounds conduct?
They conduct all of the time
