The development of the model of the atom

Scientists used alpha particles and gold to develop the atomic model.

A scientist directed alpha particles at thin gold foil.

Table 4 shows information about the direction of the alpha particles after reaching the thin gold foil.

Calculate the percentage of alpha particles that changed direction by more than 90°.

Use Table 4.

Draw one line from each observation to the conclusion that could be made from the observation.

Scientists used alpha particles and gold to develop the atomic model.

A scientist directed alpha particles at thin gold foil.

Table 2 shows information about the direction of the alpha particles after reaching the thin gold foil.

Calculate the percentage of alpha particles that changed direction by more than 90°.

Use Table 2.

Draw one line from each observation to the conclusion that could be made from the observation.

This question is about atoms.

Figure 9 represents an atom.

Label Figure 9.

Choose answers from the box.

Name the element represented by Figure 9.

Use the periodic table.

Why does an atom have an overall electrical charge of zero?

Draw one line from each description of structure size to the correct structure.

An atom of one element has a radius of 0.000 000 348 mm.

How should 0.000 000 348 mm be written in standard form?

Tick (✓) one box.

0.348 × 10^–6 mm

0.348 × 10^–7 mm

3.48 × 10^–6 mm

3.48 × 10^–7 mm

Scientists have developed different models of the atom over time.

Figure 10 shows the Dalton model of the atom and a more recent model of the atom.

Name the more recent model in Figure 10.

Give one difference between the models of the atom shown in Figure 10.

This question is about atoms.

Complete Figure 9 to represent this atom of lithium.

You should draw and label the sub-atomic particles.

Scientific models of the atom have included: the Dalton atom

the plum pudding model

the nuclear atom.

Explain why the model of the atom has changed over time.

You should refer to these three models.

An atom has a radius of 0.348 nm.

Calculate the radius of the atom in metres.

Give your answer in standard form.

In chemistry, a pure substance is a single element or compound.

Describe how measurements taken during a change of state can show if a substance is pure.

This question is about atomic structure.

An atom contains three types of particles.

Table 1 shows some information about the particles.

Complete Table 1.

Models of the atom have changed over time.

Figure 10 shows an early model of the atom.

What is the name of the model of the atom in Figure 10 ?

Tick (✓) one box.

Dalton’s model

Nuclear model

Plum pudding model

Alpha particles can be used to investigate the structure of atoms.

Alpha particles have a relative mass of 4.

What is an alpha particle?

Tick (✓) one box.

Two electrons and two neutrons

Two neutrons and two protons

Two protons and two electrons

Alpha particles from a source were directed at thin gold foil.

Figure 11 shows some of the paths the alpha particles followed.

Table 2 shows the number of alpha particles that followed paths A, B and C.

The number of alpha particles on path A was greater than the number of alpha particles on path B.

Calculate how many times greater.

The ratio of alpha particles on path B to alpha particles on path C can be shown as:

7920: 198

What is 7920: 198 written as its simplest ratio?

Tick (✓) one box.

40: 1

500: 1

8000: 1

How does Figure 11 provide evidence for a nucleus in a gold atom?

Tick (✓) one box.

Alpha particles following path C are bounced back.

Most alpha particles follow path A.

The alpha particles from the source travel in straight lines.

Figure 12 represents four atoms.

On the periodic table, helium is shown as:

Which atom in Figure 12 represents an atom of helium?

Tick (✓) one box.

W X Y Z

Which two atoms in Figure 12 represent isotopes of the same element?

Tick (✓) one box.

W and X

W and Z

X and Y

Y and Z

An atom has a radius of 0.182 nm.

Calculate the radius of the atom in metres.

1 m = 1 000 000 000 nm

The atomic model has changed over time.

Alpha particles have been used to investigate the atomic model.

Describe the structure of an alpha particle.

An atom has a radius of 0.182 nm.

1 m = 1 000 000 000 nm

What is the radius of the atom in metres?

Tick (✓) one box.

1.82 × 10⁹ m

1.82 × 10¹⁰ m

1.82 × 10⁻⁹ m

1.82 × 10⁻¹⁰ m

Alpha particles from a source were directed at thin gold foil.

Figure 6 shows some of the paths the alpha particles followed.

During one experiment the number of alpha particles following different paths was recorded.

Table 2 shows the number of alpha particles that followed paths A, B and C.

Determine the simplest ratio of alpha particles following paths A, B and C.

Simplest ratio of A: B: C = __________________: __________________: 1

Explain how the results provide evidence for the nuclear model of the atom.

Use Figure 6 and Table 2.

An atom of boron can be represented as¹¹₅B

An atom of carbon can be represented as¹²₆C

Compare the number of sub-atomic particles in the atom of boron and in the atom of carbon.

Boron and carbon both have isotopes.

What does ‘isotope’ mean?

The model of the atom has changed over time.

Draw one line from each atomic model to the representation of that model.

Scientists investigated the structure of the atom.

The scientists directed alpha particles at a thin sheet of gold foil.

What is an alpha particle the same as?

Tick (✓) one box.

A fast-moving electron

A helium nucleus

A radioactive isotope

Electromagnetic radiation

Figure 13 shows:

three of the pathways the alpha particles take

the number of alpha particles detected at positions A, B and C.

Figure 13

Determine the simplest ratio of the number of alpha particles detected at A to those detected at C.

Use Figure 13.

Simplest ratio of A: C = ____________________: 1

The scientists concluded that a gold atom:

is mostly empty space

has a charged nucleus at its centre.

How do the results in Figure 13 show that a gold atom is mostly empty space?

Explain how the results in Figure 13 show that a gold atom contains a charged nucleus.

A gold atom can be represented as:

197 Au 79

Describe the atomic structure of this gold atom.

You should include the numbers of each type of sub-atomic particle.

The model of the atom has changed over time.

Draw one line from each atomic model to the representation of that model.

Scientists investigated the structure of the atom.

The scientists directed alpha particles at a thin sheet of gold foil.

What is an alpha particle the same as?

Tick (✓) one box.

A fast-moving electron

A helium nucleus

A radioactive isotope

Electromagnetic radiation

Figure 1 shows: three of the pathways the alpha particles take the number of alpha particles detected at positions A, B and C.

Figure 1

Determine the simplest ratio of the number of alpha particles detected at A to those detected at C.

Use Figure 1.

Simplest ratio of A: C = ____________________: 1

The scientists concluded that a gold atom: is mostly empty space has a charged nucleus at its centre.

How do the results in Figure 1 show that a gold atom is mostly empty space?

Explain how the results in Figure 1 show that a gold atom contains a charged nucleus.

A gold atom can be represented as:

Describe the atomic structure of this gold atom.

You should include the numbers of each type of sub-atomic particle.