Unit 1 Flashcards
What is the pH range of a base?
More than 7.
Which ion is common to all acids?
Hydrogen/ H+
Which ion is common to alkalis?
Hydroxide/ OH-
State the four ways to speed up a chemical reaction?
Add a Catalyst.
Decrease the particle size.
Increase the temperature.
Increase the concentration.
Describe how a salt is formed.
When an acid an alkali react a salt and water are formed.
What is a precipitate?
A powdery solid formed in a chemical reaction.
When an acid and base react, what name is given to this type of reaction?
A neutralisation reaction.
What is a catalyst?
A substance that can speed up a chemical reaction but can be recovered at the end.
What is an exothermic reaction?
When heat energy is given out.
What is an endothermic reaction?
When heat energy is taken into a reaction.
What type of ions do metals form?
Positive ions.
What are spectator ions?
Ions that are not involved in a reaction but can be recognised by appearing on both sides of the equation unchanged.
Describe the separation technique-distillation.
Liquids can be separated by boiling points. The mixture is heated and the liquid with the lowest boiling point will turn into a gas. This has then passes along a cool condenser, turns back into a liquid and can then be collected at the end.
What is the charge on an electron?
Negative
What is the mass of an electron.
0
What is the charge of a proton?
Positive
What is the mass of a proton?
1
What is the charge of a neutron?
0-neutral.
What is the mass of a neutron?
1
Where in the atom are the electrons found?
Moving around the outside of the nucleus.
Name the 7 diatomic elements.
Hydrogen Nitrogen Oxygen Fluorine Chlorine Iodine Bromine
What is the pH range of an acid?
Less than 7
Give examples of different shapes of molecules.
Tetrahedral, pyramidal,bent and linear.
What does effervescence mean?
Bubbling and fizzing.
As particle size decreases what happens to the rate of reaction?
The rate increases as the surface area has been increased and there is more space for reactions to occur.
What is a covalent bond?
When two non-metals share electrons.
What is an ionic bond?
When a electrons are transferred between a metal and non metal. The metal forms a positive ion and the non metal forms a negative ion. The opposite charged ions are attracted to each other (electrostatic attraction) and this force of attraction is the ionic bond.
What is the formulae to calculate the average rate of reaction?
Change in quantity divided by change in time. This is in your data book.
What is the centre of the atom called?
The nucleus.
Name a separation technique to remove a precipitate from a liquid.
Filtration.
To measure the rate of a reaction what do we measure?
The change in volume/concentration etc of either the products or reactants of a chemical reaction with time.
What is one Gram Formulae Mass of a substance the same as?
It is the same as 1 mole of a substance.
Explain what happens to ions during electrolysis.
Positive ions would be attracted to the negative electrode. Negative ions will be attracted to the positive electrode.
Why can’t Ionic compounds conducts as solids?
Their ions are bonded together in a lattice so they are not free to move.
What are the products of electrolysis of Sodium Chloride?
Sodium and Chlorine
Why is a D.C. current used in electrolysis?
Because it keeps one electrode positive and the other negative, allowing compounds to be split into their elements.
