What is the formula of water?
H2O
Nitrogen-14 has 7 protons. How many neutrons does it have?
7
What is the chemical symbol for the element mercury?
Hg
The atomic number of an element is …
The number of protons
An atom has an atomic number of 9 and a mass number of 19. What are its numbers of protons, neutrons and electrons?
protons : 9, electrons : 9 and neutrons : 10
Four atoms have the numbers of protons and neutrons given below. Which two atoms are isotopes of the same element? W : 8 protons and 8 neutrons, X : 8 protons and 10 neutrons, Y : 10 protons and 8 neutrons, Z : 9 protons and 10 neutrons
W & X
What has an ionised atom lost or gained?
Electrons
What is nuclear fission?
The splitting of a heavy nucleus
In the current model of the atom, what are the two particles that are present in the nucleus?
Protons and neutrons
An alpha particle is…
A helium nucleus
What are isotopes?
Atoms of the same element with different numbers of neutrons
Lithium-6 has 3 protons. How many neutrons does it have?
3
Uranium-235 has 92 protons. How many neutrons does it have?
143
An atom has 13 protons and 14 neutrons. What is its mass number?
27
What is the best definition of the mass number of an element?
The total number of protons and neutrons in its atoms