Na is the symbol for which element?
Sodium
Is melting ice cream a physical or chemical change?
Physical
Is carbon dioxide an element, compound or mixture?
Compound
A lightbulb mainly produces what type of energy?
What is the Law of the Concervation of energy'?
Energy can not be created or destroyed
What is the symbol for Lead
Pb
If we reduce the heat applied to a chemical reaction, is the reaction sped up or slowed down?
Slowed down
What are the three subatomic particles, and what charge do they each have?
Proton (+), Neutron (N) and Electron (-)
What two forms of energy are produced when you light a match? (note: this question is not asking for the type of energy is used to light the match)
Heat and Light energy
What is meant by the term 'potential energy'?
Energy that is not being used, but has the potential to occur
Fill in the blank:
Atomic Number is the number of ___________ that an element has (which is also the number of ____________)
electrons
(which equals protons when considering elements on the periodic table that are all balanced)
If an object gives off gas during a reaction, is it going through a chemical or physical change?
Chemical
Which sub-atomic partical orbits the nucleus?
Electron
Gravitational potential energy
What path does energy take within a battery powered torch when it is used?
Chemical to electrical to light
Fill in the blank:
Atomic Mass = _____________ + ______________
Protons + Neutrons
What are three criteria that can occur within a physical reaction?
Change of size, shape, texture, temperature and/or state.
How do we classify an object as an element? (as in, how do we know it is an element and not something else?)
It only contains one type of particle
Elastic / Eleastic Potential
Describe the main pathway of energy conversion of a ball that is bounced from the time it is dropped till the maximum height of the first bounce
Gravitational potential to kinetic to elastic potential to kinetic to gravitational potential
Silicon has an atomic number of 14. Understanding the relationship between atomic number and the balanced nature of elements on the periodic table (protons = electrons), that silicon's atomic mass = 28 and the fact that atomic mass = protons - neutrons, work out how many neutrons silicon has.
14
A substance that doesn't involve itself in the reaction and speeds up the reaction rate of the chemical reaction.
How do a compound and mixture differ?
Compounds are substances formed by the chemical combination of two or more elements. Mixtures are substances formed by physically mixing two or more substances together
What is the name of the form of kinetic energy that resists two objects that are being rubbed together?
Friction
An appliance has and energy input of 500 units and an energy output of 100 units. What is its efficiency?
Energy efficiency = (energy output/energy input) x 100
100/500 x 100 = 20