Choose the element described by each of the following.
(Each element can be selected only once.)
Carbon is considered to be an element because:
all of its atoms have the same atomic number
one of its isotopes has a mass number of 12
it is a substance present in all living things
it has the same number of protons as neutrons in its nucleus
The total number of electrons in a positive, doubly-charged ion of an element with atomic number 12 is:
8
10
12
14
Which of the following correctly defines the mass number of a given atom?
the total mass of neutrons and protons in the nucleus of the atom
the total mass of neutrons, protons and electrons in the atom
the number of protons in the nucleus of the atom
the total number of neutrons and protons in the nucleus of the atom
Which of the following in the list below displays all physical changes?
shredding paper, cooking an egg, ice melting, iron rusting
ice melting, cooking an egg, igniting a match, shredding paper
shredding paper, melting chocolate, grating cheese, boiling water
melting chocolate, igniting a match, shredding paper, iron rusting
Consider the following observations and state what TYPE of chemical reaction is involved.
A student added hydrochloric acid to a test tube containing sodium hydroxide at a pH of 9. She noticed that the pH of the solution changed to 7 when the sodium hydroxide was added.
decomposition
combination
precipitation
neutralisation
Consider the following observations and state what TYPE of chemical reaction is involved.
A student added some copper sulphate solution to a test tube containing a nail. After sitting for 5 minutes he noticed that the nail had a brown coating and that the solution appeared to be paler in colour.
single displacement
double displacement
precipitation
decomposition
Which of the following statements regarding atomic particles is false?
Protons are found in the nucleus and are positively charged particles
Electrons move around the nucleus and contribute little to the mass of the atom
Neutrons are found in the nucleus and they have no charge
The numbers of neutrons, protons and electrons are always equal in a neutral atom
Refer to the diagram above. This ion contains:
12 protons, 12 neutrons and 12 electrons
12 protons, 12 neutrons and 14 electrons
12 protons, 10 neutrons and 10 electrons
12 protons, 12 neutrons and 10 electrons
The electron configuration for Al^3+is:
2,8,3
2,8
2,8,6
2,8,2
How many ‘p’ orbitals are to be found in any given shell?
1
2
3
4
A neutral atom of silver has the atomic number (Z) = 47 and mass number (A)= 107. Examine the information below and decide which alternative correctly shows the numbers of protons, electrons and neutrons for the silver atom.
P= protons, E= electrons, N= neutrons
47 P, 47 E and 107 N
47 P, 47 E and 60 N
107 P, 107 E and 47 N
47 P, 60 E and 47 N
Atoms of the same element which have the same number of protons but a different number of neutrons are known as:
ions
isotopes
neutral atoms
a chemical family
The electron configuration: 2, 8, 4 is that of:
carbon
nitrogen
neon
silicon
An element has the following ground state electron configuration:
1s2 2s2 2p5
How many ‘valence’ electrons does this atom have?
1
2
5
7
The ground state electron configuration for nitrogen is:
1s2 2s2 2p6 3s2 3p2
1s2 2s2 2p3
1s2 2s2 2p2 4s1
1s2 2s2 2p
‘d – block’ elements are found in:
the left hand side of the periodic table.
the upper right hand side of the periodic table.
the middle of the periodic table
the Lanthanide and Actinide series of the periodic table.
Which one of the following is the most important factor that determines the chemical properties of an element?
The number of protons in the nucleus of the atom.
The total number of electrons in the atom.
The number of valence electrons in the atom.
The number of neutrons in the nucleus of the atom.
An element has the following ground state electron configuration:
1s2 2s2 2p6 3s2 3p6 4s2
Based on this information, the element would most likely belong to which group in the periodic table?
Group I
Group II
Group III
Group IV
The properties of the elements that change across a period in the periodic table are
I: electronegativity
II: number of electrons in the outer shell
III: metallic character.
Moving across period 3 from sodium to chlorine, which of these properties increase?
I only
I and II only
II and III only
I, II and III
Refer to the diagram above.
The following graphs show trends with increasing atomic number in atomic properties across period 2. Which graph best represents the trend in the electronegativity of each element?
