C2 Questions

Question 1

The plum pudding model suggests that most of the atom is…

Answer 1

The plum pudding model suggests that most of the atom is positive ‘dough’. The plum pudding model was introduced to explain the two types of charge; positive and negative.

Question 2

What was the surname of the scientist who suggested the plum pudding model?

Answer 2

J J Thomson suggested the Plum pudding model in 1897.

Question 3

What did Ernest Rutherford direct at a thin gold leaf in 1905?

Answer 3

Alpha particles were scattered from a gold foil in this famous experiment.

Question 4

Most alpha particles going straight through the gold foil tells us that …

Answer 4

The atom is mostly space and most of the alpha particles miss the nucleus completely.

Question 5

What did Niels Bohr add to the Rutherford Atomic model?

Answer 5

Niels Bohr added electron orbits to the Rutherford model. The conclusion from Rutherford’s experiment was that the nucleus existed.

Question 6

The Rutherford scattering experiment proved the existence of what?

Answer 6

The Rutherford scattering experiment proved the existence of the nucleus. No one scientist has ever been credited for discovering the proton.

Question 7

Who discovered the neutron?

Answer 7

James Chadwick discovered the neutron in 1932.

Question 8

Why did Rutherford use gold foil in his experiment?

Answer 8

Gold can be made very thin so that the alpha particles can get through it.

Question 9

In the current model of the atom, what are the two particles that are present in the nucleus?

Answer 9

Protons and neutrons are found in the nucleus, electrons orbit the nucleus.

Question 10

How many times bigger is the atom compared to the nucleus?

Answer 10

The atom is at least 10,000 times bigger than the size of the nucleus.

Question 11

How many neutrons does 146C contain?

Answer 11

Number of neutrons = mass number - atomic number = 14 - 6 = 8 neutrons.

Question 12

What is the relative mass of the proton?

Answer 12

Protons (and neutrons) have a relative mass of 1. Electrons have a mass of 1/2,000 that of a proton and are often thought of as having no relative mass.

Question 13

What is the relative charge of a neutron?

Answer 13

The relative charge of a neutron is 0. Neutrons are neutral and have no charge

Question 14

What is an isotope?

Answer 14

A nucleus with the same number of protons but different number of neutrons is called an isotope.

Question 14

Uranium-235 has 92 protons. How many neutrons does it have?

Answer 14

Uranium-235 has 143 neutrons. 92 is the number of protons.

Question 15

Nitrogen-14 has 7 protons. How many neutrons does it have?

Answer 15

Nitrogen-14 has 7 neutrons. Mass number - proton number = number of neutrons. 14 - 7 = 7.

Question 16

The mass number of an element is …

Answer 16

The mass number of an element is the number of protons and neutrons. Sometimes also called the nucleon number

Question 17

The atomic number of an element is …

Answer 17

The number of protons is called the atomic number. Atoms of the same element may have different numbers of neutrons.

Question 18

What has an ionised atom lost or gained?

Answer 18

An ionised atom has lost or gained electrons. An ion is an atom that has lost or gained electrons.

Question 19

What has changed in the structure of the Cu2+ ion?

Answer 19

It has lost two electrons. If it has gained two electrons it would be a 2- ion as electrons are negatively charged.

Question 20

Why is deuterium 2,1 H
sometimes called heavy hydrogen?

Answer 20

It has an extra neutron. An extra proton would make it helium.

Question 21

True or false, The vertical columns are called periods.

Answer 21

False

Question 22

Elements in the same period:

Answer 22

Elements in the same period have the same number of electron shells.

Question 23

True or false, Elements in Group 7 become more reactive as you move up the group is the true statement.

Answer 23

True

Question 24

Elements in the transition element block of the periodic table:

Answer 24

Elements in the transition element block of the periodic table have ions of the same element with different charges.

Question 25

Which of the following reactions actually occurs as written?

Answer 25

The reaction: Cl2 + 2NaI → 2NaCl + I2 actually occurs as written.

Question 25

Which statement correctly describes the changes Mendeleev made in the development of the periodic table?

Answer 25

The correct statement is: He arranged the elements in order of atomic weight, swapped some elements so that elements in the same group had similar properties and left gaps for undiscovered elements.

Question 26

Which of the following equations represents the balanced symbol equation for the reaction of potassium with water?

Answer 26

The correct answer is 2K + 2H2O → 2KOH + H2

Question 27

True or False, Elements increase in reactivity across the periodic table.

Answer 27

False

Question 28

The half equation for the formation of potassium ion from a potassium atom is represented as:

Answer 28

The half equation for the formation of potassium ion from a potassium atom is represented as K → K+ +e-

Question 29

The half equation for the formation of chloride ions from a chlorine molecule is represented as:

Answer 29

The half equation for the formation of chloride ions from a chlorine molecule is represented as Cl2 + 2e- → 2Cl-

Question 30

Write the word equation and balanced equation for the reaction of potassium with water.

Answer 30

potassium + water → potassium hydroxide + hydrogen

2K(s) + 2H2O(l) → 2KOH(aq) + H2(g)

Question 30

The table above shows the melting points of five alkali metals. Use this information to describe how melting point changes in group 1.

Answer 30

Going down group 1, the melting point decreases.

Question 31

Use the information in the table to predict the melting point of francium, Fr. Explain your answer.

Answer 31

The melting point of francium will be around 27°C. This is because francium is below caesium in the periodic table, so it should have a lower melting point, and the difference in melting point decreases going down from one element to the next.