Y10 Definitions

Question 1

Brownian motion

Answer 1

The random motion of particles suspended in a liquid or gas that occurs because the particles are continually bombarded by molecules

Question 2

Diffusion

Answer 2

The random movement of particles from a region of higher concentration to a region of lower concentration

Question 3

Proton number (atomic number)

Answer 3

The number of protons in the nucleus of an atom

Question 4

Nucleon number (mass number)

Answer 4

The total number of protons and neutrons in the nucleus of an atom

Question 5

Isotopes

Answer 5

Atoms of the same element which have the same proton number but a different nucleon number

Question 6

Alloy

Answer 6

A mixture of a metal with other elements

Question 7

Allotropes

Answer 7

Different forms of the same element in the same physical state

Question 8

Relative atomic mass

Answer 8

The average mass of naturally occurring atoms of an element on a scale where the carbon-12 atom has a mass of exactly 12 units

Question 9

Relative molecular mass

Answer 9

The sum of the relative atomic masses (of a molecule)

Question 10

Relative formula mass

Answer 10

The sum of the relative atomic masses (of an ionic compound)

Question 11

Mole

Answer 11

One mole of a substance is the amount that contains the same number of units as the number of carbon atoms in 12 grams of carbon-12

Question 12

Avogadro constant

Answer 12

The number of particles in one mole of an element or compound; it is 6.02 x 10^23

Question 13

Electrolysis

Answer 13

The breakdown of an ionic compound, when molten or in aqueous solution, by the passage of electricity