C1.1-C1.7

Relative charge of proton

+1

Relative charge of electron

-1

An atom of an element always contains...

...equal numbers of protons and electrons

Relative charge of neutron

0

Relative mass of neutron

1

Relative mass of proton

1

A normal sample of chlorine contains only chlorine-35 and chlorine-37 atoms. Explain why the relative atomic mass of chlorine is 35.5.

1) average (mass of atoms/isotopes present) 2) more chlorine-35 than chlorine-37 / higher {percentage / abundance} of Cl-35 / lower {percentage / abundance} of Cl37 / (1)

Relative mass of electron

1/1837

State the total number of atoms in the formula: Al(NO3)3 (aluminium nitrate)

13 atoms

What is the most likely formula for aluminium nitride?

AlN

Choose the symbol which is in group 2 of the periodic table: Ca Cl K N Ne O

Ca (calcium)

Chlorine has an atomic number of 17. Chlorine-35 and chlorine-37 are two isotopes of chlorine. Name the number of neutrons in chlorine-35 and chlorine-37.

Chlorine-35= 17 Chlorine-37= 17

Chlorine has an atomic number of 17. Chlorine-35 and chlorine-37 are two isotopes of chlorine. Name the number of protons in chlorine-35 and chlorine-37.

Chlorine-35= 17 Chlorine-37= 17

Chlorine has an atomic number of 17. Chlorine-35 and chlorine-37 are two isotopes of chlorine. Name the number of electrons in chlorine-35 and chlorine-37.

Chlorine-35= 18 Chlorine-37= 20

Position of neutron in atom

In nucleus

Position of proton in atom

In nucleus

Position of electron in atom

In shells

Choose the symbol readily forms an ion with a charge of -2: Ca Cl K N Ne O

O (oxygen)