topic 1 key words Flashcards
(33 cards)
What is the definition for atmosphere?
The thin layer of air surrounding the Earth.
What is the Bohr Model?
A model of the atom that suggested that negative electrons orbit a positive nucleus at set distances. it is the currently accepted model.
What is the definition for change in thermal energy?
The product of mass, specific heat capacity and temperature change of a substance.
What are chemical changes?
Changes to the chemical structure of a substance. Not reversable.
What is condensation?
The changing from vapour state to a liquid state, when a substance is cooled.
What is density?
The mass per unit volume of an object.
What are electrons?
A negatively charged constituent of the atom, they are found in different energy levels, around the nucleus.
What is a liquid?
A liquid or gas.
What is evaporation?
the changing from a liquid state to a vapour state, when a substance is heated.
What is freezing?
The changing from a liquid state to a solid state, when a substrate is cooled.
What is a gas?
A state of matter in which the particles are spread far apart and have high kinetic energies.
What is latent heat?
The energy required for a substance to change state.
What is a liquid?
A state of matter in which the particles are in contact, but can flow over each other.
What is melting?
The changing from a solid state to liquid state, when a substance is heated.
What is the nucleus?
The positively charged centre of an atom, containing protons and neutrons
What are neutrons?
A neutrally charged constituent of the nucleus.
What are pascals?
The unit of pressure, equal to a force of one Newton acting perpendicular to an area of one metre squared.
What are physical changes?
Changes to the physical properties of a substance which can be reversed.
What is pressure in a liquid column?
Equal to the product of the height of the column, the density of the liquid and the gravitational field strength.
What is pressure?
The force acting perpendicular to a surface, per unit area.
What is the pressure of a gas?
The perpendicular force per unit area acting on the surfaces of a container as a result of the gas particles colliding with it.
What are protons?
A positively charged constituent of the nucleus.
What is the Rutherford model?
A model of the atom that represented that atom as being mostly empty space, with a dense positive centre and negative charges scattered around it.
What is a solid?
A state of matter in which the particles are tightly packed together and can only vibrate about their fixed positions.
