Chemistry - Ch. 5 (Yr 10) Flashcards
What is the ‘law of mass of conservation’ ?
Bonds break and reform in chemical reactions but no atoms are destroyed nor created, therefore, the mass remains the same.
What does the rearranging of atoms do in terms of mass and products?
The mass stays the same and the products are different from the reactants.
What does a ‘catalyst’ do?
It speeds up reactions.
The number of atoms in the reactants must be ……. to the amount in the products. (Fill in the gap)
Equal
What are the subscripts and their symbols?
S = solid
g= gas
l= liquid
aq = Aqueous
What does ‘aqueous’ (aq) mean?
Soluble in water
How do you balance an equation?
Count the amount of each element, then add numbers ONLY in front of the elements to make them equal on each side.
What is the general equation of a synthesis reaction?
A+B —> AB
The combining/making.
What is the general equation of a decomposition reaction?
AB —> A+B
Breaking down
What is synthesis?
The forming of compounds by combining simpler elements and substances.
What is decomposition?
The breaking down of compounds into their simpler substances.
What is the general equation for a neutralisation reaction?
Neutralisation:
acid (pH 1-6) + base (pH 8-14) —> water (pH 7) + salt
What ions do acids contain?
Hydrogen ions (H+)
What ions do bases contain?
Hydroxide ions (OH-)
The reactants ‘Acid + metal oxide’ create a product of?
Salt + water
The reactants ‘Acid + metal’ create a product of?
Salt + Hydrogen
The reactants ‘Acid + metal carbonate’ create a product of?
Salt + water + carbon dioxide
High concentration means? How does this affect an acids ability to give its ions?
High strength.
Strong acids are more readily to give away H+ ions to a base
What is ‘precipitate’?
A solid formed by a precipitation reaction which is insoluble in the product.
What is the general equation for a single replacement precipitation reaction?
A(aq) + B(aq) —> AB(aq) + C (s)
What is a single replacement precipitation reaction?
The rearrangement of elements, isolating a different element.
What is the general equation for a double replacement precipitation reaction?
AB(aq) + CD(aq) —> AC(aq) + BD(s)
What is a double replacement precipitation reaction?
Rearrangement or elements (swapping pairs), forming one solid in the product.
What is a spectator ion?
The soluble products of a reaction, in relation to precipitation reactions.
Eg. AC(aq)
What is an oxidation reaction with metal?
Metal + oxygen —> metal oxide
What is an oxidation reaction with non metals?
Non metal + oxygen —> non metal oxide
What is a general worded equation of a COMPLETE hydrocarbon combustion reaction?
Hydrocarbon + unlimited oxygen —> carbon dioxide + water
What is a general worded equation of a IN-COMPLETE hydrocarbon combustion reaction?
Hydrocarbon + limited oxygen —> carbon monoxide + water?
Carbon monoxide is a toxic, transparent and odourless gas.
What does extremely low oxygen form?
Soot (unburnt carbon) and water
What element group from the periodic table don’t react with oxygen?
Group 18
What is a polymer?
Polymers are long chains of monomers.
Many parts of
What are monomers?
Smaller molecules that form polymers
What are the three types of polymers?
Linear polymer, cross linked polymer (elastomers), and thermoplastic polymers (plastic).
What is the difference between a ‘thermoplastic polymer’ and a ‘thermo setting polymer’?
Thermoplastic:
- Malleable when heated
Thermo setting polymer:
- not malleable (doesn’t melt)
- hard, rigid and can go black when hot
What must a polymerisation reaction have?
High temperature, pressure and a catalyst
What is collision theory?
The colliding of particles/atoms to form a reaction.
An increased collision causes an ….. reaction rate. (Fill in gap)
Increased
List 4 ways to increase collision?
Surface area, concentration, temperature (kinetic energy), and agitation (stirring)
What’s a catalyst?
Increases the rate of a reaction without permanently changing anything
How does a catalyst affect activation energy?
They lower the activation energy required for a reaction to occur, making it easier for atoms to break and form chemical bonds.
What does a positive catalyst do?
Increase reaction rate
What does a negative catalyst do?
Decreases reaction rate
