Chemistry Flashcards
I'm gonna smash this mock - I'm scared.
A teacher extracted copper from copper oxide. box
This is the method used.
1. Mix 1.30 g of zinc and 1.59 g of copper oxide.
2. Heat the mixture strongly.
3. When the mixture starts to glow, stop heating.
4. Let the glow spread through the mixture.
5. Leave the mixture to cool
Which part of the method shows the reaction is exothermic?
Let the glow spread
What type of reaction takes place when zinc reacts with copper oxide?
Displacement
Why is copper used in electrical wiring?
-It is a good electrical conductor
-Can be bent easily
Is Lithium Oxide a compound, element, metal, mixture or polymer?
Compound
Give two factors that can affect reaction time
Age, Alcohol, Distractions, Drugs
How do you measure stopping distance of a car?
Complete the sentence:
The greater the speed, ____________________________________
The greater the braking distance
Give two disadvantages of applying a large braking force.
-Brakes overheat
-Car goes out of control
What is an alloy
A mixture of metals.
Give one reason why alloys are used instead of pure metals
-Alloys are harder
-They are corrosion resistant
Bar magnets are described as __________ magnets
A) Induced 2)Permanent 3) Temporary
Permanent
The magnetic field is strongest at the __________________
poles of the magnet
What do you use to measure the temperature of a solution?
Thermometer
What do use to measure the volume of hydrochloric acid?
Measuring cylinder
Complete the word equation for the reaction:
Hydrochloric acid + sodium hydroxide > ________________ + _______________
Sodium chloride + Water
What is the the typical mean speed for a person cycling?
A) 3.0 m/s B) 4.5 m/s C) 6.0 m/s
6.0 m/s
What does the area under a velocity-time graph represent
Distance travelled
Why is hydrogen chloride not able to conduct electricity but hydrochloric acid is?
-hydrogen chloride molecules do
not have an overall electric
charge
-hydrochloric acid contains ions
-(which) are free to move so
charge can flow
What is direct current?
Current that always passes in the same direction
Why are chloride ions attracted to the positive electrode
Because they are negatively charged
The step-up transformer causes the potential difference to increase and the current to…
a) Decrease b) Increase
Decrease
The use of the step-up causes the energy transferred by heating of the cables to…
a) Decrease b)Increase
Decrease
The step-down transformer causes the potential difference to decrease and the current to…
a)Decrease b) Increase
Increase
What produces acid rain?
Sulfur dioxide