OCR AS Chemistry

ThornleighSalesian College Applied Science Pre-Course Task 2017

CHEMISTRY

Complete the following table. The first few have been done for you

element / symbol / atomic number / mass number / number of protons / number of neutrons / number of electrons / electron arrangement
hydrogen / H / 1 / 1 / 1 / 0 / 1 / 1
lithium / Li / 3 / 7 / 3 / 4 / 3 / 2,1
boron / 11
magnesium / 24

(2 marks total)

Draw an electron diagram to show the electron arrangement of an atom for the following elements.
nitrogen
phosphorus

(2 marks total)

Ionic bonding and properties of ionic compounds

Draw the dot and cross diagram for aluminium oxide(draw outer shells and the resulting bond only).

(2 marks total)

Fill in the table to show the electron arrangements for the following ions:

ion / electron arrangement / ion / electron arrangement
K+ / F-
S2- / Mg2+
Al3+ / N3-

(3 marks total)

Covalent bonding and properties of covalent compounds

Draw ‘dot and cross’ diagrams showing all the electrons in the following molecules:

Carbon dioxide (CO2)

(2 marks total)

Balancing Equations.

Balance the following equations:

C2H6(g) + O2 (g) → CO2 (g) + H2O(l)
Fe(s) + O2(g) → Fe2O3(s)

(2 marks total)

Chemical calculations

The empirical formula of this ionic compound can be calculated from its percentage composition by mass: Rb, 7.42%; Ag, 37.48%; I, 55.10%.Calculate the empirical formula of the compound showing your working clearly.

(2 marks total)

Barium metal can be extracted from barium oxide, BaO, by reduction with aluminium.Calculate the mass of barium metal that could be produced from reduction of 500g of barium oxide using this method.

6BaO + 2Al 3Ba + Ba3Al2O6

answer = ...... g (2 marks total)

Fill in the missing words and answer the questions.

Diamond

In the bulk of the structure each carbon is joined to _____ other carbon atoms by ______bonds.

Explain why diamond has a high melting temperature

(3 marks total)

Graphite

Each carbon atom is bonded to ____ other carbon atoms by ______bonds, forming hexagonal rings. The fourth electron from each carbon atom is______between the flat layers of hexagons. The ______forces between the layers of hexagons are weak so the layers can slip over each other making graphite relatively soft.

Explain why graphite conducts electricity

(4 marks total)

Chemistry / 24 marks

BIOLOGY

Q1a.

1b.

(9 marks total)

(3 marks)

(4 marks total)

(9 marks total)

Q4. The diagram (see below) shows a bacterial cell and a plant cell.

(2 marks total)

Biology / 24 marks

PHYSICS

Wave Exam Style Questions
Q1. Small water waves are created in a ripple tank by a wooden bar. The wooden bar vibrates up and down hitting the surface of the water.

The figure below shows a cross-section of the ripple tank and water.

(a)Which letter shows the amplitude of a water wave?

Circle one.
J, K, L

(1)

(b)The speed of the wooden bar is changed so that the bar hits the water fewer times each second.

What happens to the frequency of the waves produced?

Circle one:
Increases, does not change, decreases

(1)

(c)Describe how the wavelength of the water waves in a ripple tank can be measured accurately.

......

(2)

(d)The speed of a wave is calculated using the following equation.

wave speed = frequency × wavelength

The water waves in a ripple tank have a wavelength of 1.2 cm and a frequency of 18.5 Hz. How does the speed of these water waves compare to the typical speed of a person walking?

......

...... (4)

(8 marks total)

Q2.Bats use the reflection of high pitched sound waves to determine the position of objects.

The image below shows a bat and an insect flying in front of the bat.

(a) What determines the pitch of a sound wave? Tick (✔) one box.

Tick (✔)
amplitude
frequency
speed

(1)

(b) State the name given to reflected sound waves.

......

(1)

Calculate the speed of this sound wave.

......

Speed = ...... m/s

(2)

(d) Sound waves are longitudinal. Describe a longitudinal sound wave.

......

(2)

(Total 6 marks)

Electromagnetic spectrum Exam style questions

Q3.(a) The visible light spectrum has a range of frequencies. The figure below shows that the frequency increases from red light to violet light.

Increasing frequency

Red / Green / Violet

Use the correct answers from the box to complete the sentence.

decreases / stays the same / increases

As the frequency of the light waves increases, the wavelengthof the light waves

...... and the energy of the light waves......

(2)

(b) Bottled beer will spoil if the intensity of the light passing through the glass bottle into the beer is too high. The Figure below shows the intensity of the light that is transmitted through three different pieces of glass.

Wavelength × 10– 9 in metres

(i)The pieces of glass all had the same thickness. Suggest why.

......

(1)

(ii)Bottles made of brown glass are suitable for storing beer. Suggest why.

......

(1)

(Total 4 marks)

Q4. (a) Electromagnetic waves have many uses. The diagram shows two ways of sending information using electromagnetic waves.

(i) What type of wave is used to send information to and from satellites?

......

(1)

(ii)What property of this type of wave makes it suitable for satellite communications?

......

(1)

(b) Different frequency radio waves travel different distances through the atmosphere before being reflected.

Use the information in the diagram to describe the connection between the frequency of a radio wave and the distance the radio wave travels through the atmosphere before it is reflected.

......

(1)

(3 marks total)

Q5. Different wavelengths of light can be used to transmit information along optical fibres.

The graph below shows how the percentage of incident light transmitted through a fibre varies with the wavelength of light and the length of the fibre.

Wavelength × 10−7metres

Compare the percentages of incident light transmitted through the two different fibres over the range of wavelengths shown.

......

(Total 3 marks)

PHYSICS = /24