Unit 1: Chemical Changes and Structure

Concentration Particle Size Temperature Use of a Catalyst

Measuring: • Changes in Mass(At Regular Time Intervals) • Changes in Volume (At Regular Time Intervals) • Changes inConcentration (At Regular Time Intervals)

Particles colliding with each other

Particles have more energy and move quicker causing more frequent collisions with more energy

Increased surface area means a higher chance of particles colliding

More particles moving means more particle collisions

Average Rate = Change in measurable Quantity/Change in Time Units depend on measurable quantity and time

Steeper Gradient = Faster Reaction Flat/Straight line = End of Reaction

Particles that make up everything. Made from protons, neutrons and electrons

Negatively charged particles that orbit the nucleus. Their mass is so small it is nearly 0

Positively charged particles contained in the nucleus of the atom. Have a mass of 1amu

Particled with no charge that are also contained in the nucleus. Have a mass of 1amu

Centre of an atom made up from protons and neutrons. Has an overall positivie charge

Alkali Metals. React rapidly with water, producing an alkaline solution and hydrogen gas

Noble Gases. Very unreactive and exist as individual atoms

How many protons an element has

Number of protons and neutrons in an atom

Atoms with the same atomic number but different mass numbers

Calclated from the masses of all the isotopes of an element taking into account the percentage proportion of each

A shared pair of electrons between two non-metal atoms

Bromine Iodine Chlorine Fluorine Oxygen Hydrogen Nitrogen

One shared electron

Two shared Electrons

Three Shared Electrons