atomic theory

Question 1

element

Answer 1

substance tat cannot be broken down into simpler substances by chemical means

Question 2

atom

Answer 2

smallest part of an element that still retains the properties of that element

Question 3

molecule

Answer 3

the smallest part of an element or compound that can exist independently

Question 4

compound

Answer 4

when two or more substances combine together chemically

Question 5

mixture

Answer 5

when 2 or more substances are mingled together but not chemically combined

Question 6

atomic number

Answer 6

smaller number
tells us the number of protons in an atom of an element

Question 7

mass number

Answer 7

larger number
tells us the number of protos and neutrons together

Question 8

isotopes

Answer 8

atoms of the same element that have the same atomic numbr but differen mass numbers

Question 9

relative atomic mass

Answer 9

average mass of all the isotopes taking their natural abundances into account

Question 10

atomic orbital

Answer 10

region of space around a nucleus where an electron is most likely to be foun

Question 11

valency

Answer 11

the number of electrons an atom of an element is willing to give take or share in forming chemical bonds

Question 12

transitions elements

Answer 12

metals that have an incomplete d sub shell or the last electron goes into the second last shell

Question 13

ion

Answer 13

an atom or group of atoms with a charge

Question 14

ionisation energy

Answer 14

the first ionisation energy of an element is the minimum amount of energy required to completely remove the most loosely bound electron from an isolated atom of that element in its most gaseous state