GCSE Combined Science Foundation Paper 4
Covers Cell Biology, Organisation, Infection and Response and 9 more.
Questions
Question 1 [2 marks]
Quantitative Chemistry
Carbon dioxide has the formula CO2 and a relative formula mass of 44.
Calculate the number of moles in 22 g of carbon dioxide.
Question 2 [2 marks]
Bonding, Structure and the Properties of Matter
Sodium chloride is an ionic compound.
State the type of bonding found in sodium chloride, and name the particles held together by this bonding.
Question 3 [2 marks]
Bioenergetics
Photosynthesis is the process by which plants make glucose, using carbon dioxide and water.
Write the balanced symbol equation for photosynthesis.
Question 4 [2 marks]
Chemical Changes
Acids react with metal hydroxides in neutralisation reactions.
State the two products formed in the general reaction between an acid and a metal hydroxide.
Question 5 [3 marks]
Organisation
Blood is made up of plasma, red blood cells, white blood cells and platelets.
State the function of plasma, red blood cells and platelets in the blood.
Question 6 [3 marks]
Cell Biology
Animal cells contain several subcellular structures, each with a specific function.
Describe the function of the nucleus, the mitochondria and the ribosomes in an animal cell.
Question 7 [3 marks]
Electricity
A resistor of resistance 5 ohms has a potential difference of 12 V across it.
Calculate the current flowing through the resistor. Use V = I R.
Question 8 [4 marks]
Particle Model of Matter
A liquid has a mass of 158 g and occupies a volume of 200 cm^3.
Calculate the density of the liquid, and state whether the liquid would float or sink in water, which has a density of 1.0 g/cm^3.
Question 9 [4 marks]
Atomic Structure and the Periodic Table
Before the discovery of the electron, atoms were thought to be tiny spheres that could not be divided.
Describe the plum pudding model of the atom, and describe how the results of the alpha particle scattering experiment led scientists to replace it with the nuclear model.
Question 10 [4 marks]
Forces
A resultant force of 600 N acts on a car of mass 1500 kg.
Calculate the acceleration of the car. Use F = m a.
Question 11 [4 marks]
Infection and Response
A single bacterium divides by binary fission every 20 minutes on a nutrient agar plate.
Starting with 1 bacterium, calculate the number of bacteria present after 3 hours, assuming unlimited nutrients.
Question 12 [4 marks]
Energy
A crane lifts a load of mass 250 kg through a height of 12 m.
Calculate the gravitational potential energy gained by the load. Use GPE = m g h, with g = 9.8 N/kg.
Question 13 [4 marks]
Particle Model of Matter
A fixed mass of gas has a volume of 0.80 m^3 at a pressure of 150 kPa.
The gas is compressed at constant temperature until its pressure increases to 400 kPa.
Calculate the new volume of the gas. Use p1 V1 = p2 V2.
Question 14 [4 marks]
Organisation
A student investigates the effect of temperature on the activity of amylase, using iodine solution to test for starch.
At 35 degrees C, the starch was fully broken down in 40 seconds.
Calculate the rate of this reaction in s^-1. Use rate = 1 / time (s).
Question 15 [5 marks]
Bioenergetics
A student investigates the rate of photosynthesis in pondweed by counting bubbles of oxygen released.
At a light intensity of 400 lux, 45 bubbles are released in 3 minutes.
At a higher light intensity, 75 bubbles are released in the same time.
Calculate the percentage increase in the rate of bubble production caused by the higher light intensity. Give your answer to 1 decimal place.
Question 16 [5 marks]
Atomic Structure and the Periodic Table
Group 0 of the periodic table contains the noble gases.
Explain, in terms of electronic structure, why the noble gases are unreactive, and describe two other physical properties of the noble gases.
Question 17 [5 marks]
Chemical Changes
Excess magnesium ribbon is added to 50 cm^3 of hydrochloric acid of concentration 2.0 mol/dm^3: Mg + 2HCl -> MgCl2 + H2.
Calculate the maximum mass of magnesium chloride that could be produced. Relative formula mass of MgCl2 = 95.
Model solutions
| Question 1[2 marks] | |
|---|---|
| Answer or working | Marks |
| using moles = mass / relative formula mass | M1 |
| 0.5 mol | A1 |
| Question 2[2 marks] | |
|---|---|
| Answer or working | Marks |
| ionic bonding | B1 |
| ions (Na+ and Cl- ions) | B1 |
| Final answer: Ionic bonding between Na+ and Cl- ions | |
| Question 3[2 marks] | |
|---|---|
| Answer or working | Marks |
| 6CO2 + 6H2O as the reactants | B1 |
| C6H12O6 + 6O2 as the products | B1 |
| Final answer: 6CO2 + 6H2O -> C6H12O6 + 6O2 | |
| Question 4[2 marks] | |
|---|---|
| Answer or working | Marks |
| salt as a product | B1 |
| water as a product | B1 |
| Final answer: salt + water | |
| Question 5[3 marks] | |
|---|---|
| Answer or working | Marks |
| plasma transporting dissolved substances such as glucose, carbon dioxide and urea around the body | B1 |
| red blood cells transporting oxygen (bound to haemoglobin) around the body | B1 |
| platelets helping the blood to clot at a wound | B1 |
| Final answer: Plasma transports dissolved substances; red blood cells carry oxygen; platelets help blood clot | |
| Question 6[3 marks] | |
|---|---|
| Answer or working | Marks |
| nucleus: controls the cell's activities / contains genetic material (DNA) | B1 |
| mitochondria: site of (aerobic) respiration, releasing energy | B1 |
| ribosomes: site of protein synthesis | B1 |
| Final answer: Nucleus controls activities; mitochondria release energy in respiration; ribosomes make protein | |
| Question 7[3 marks] | |
|---|---|
| Answer or working | Marks |
| rearranging to I = V / R | M1 |
| substituting 12 / 5 | M1 |
| 2.4 A | A1 |
| Question 8[4 marks] | |
|---|---|
| Answer or working | Marks |
| using density = mass / volume | M1 |
| substituting 158 / 200 | M1 |
| 0.79 g/cm^3 | A1 |
| stating the liquid would float on water, as its density is less than that of water | B1 |
| Final answer: 0.79 g/cm^3; the liquid would float on water | |
| Question 9[4 marks] | |
|---|---|
| Answer or working | Marks |
| describing the plum pudding model as a ball (sphere) of positive charge with negative electrons embedded in it | B1 |
| stating most alpha particles passed straight through the (gold) foil in the scattering experiment, showing atoms are mostly empty space | B1 |
| stating a small number of alpha particles were deflected or bounced back, showing the atom has a small, dense, positively charged nucleus | B1 |
| stating the nuclear model that replaced it has a small nucleus with electrons orbiting around it | B1 |
| Final answer: Plum pudding model: a ball of positive charge with electrons embedded in it. Alpha scattering showed atoms are mostly empty space with a small, dense, positive nucleus, leading to the nuclear model with electrons orbiting the nucleus | |
| Question 10[4 marks] | |
|---|---|
| Answer or working | Marks |
| rearranging to a = F / m | M1 |
| substituting 600 / 1500 | M1 |
| 0.4 | A1 |
| the unit m/s^2 | B1 |
| Final answer: 0.4 m/s^2 | |
| Question 11[4 marks] | |
|---|---|
| Answer or working | Marks |
| finding the number of 20-minute divisions in 3 hours, 180 / 20 = 9 | M1 |
| using 2 raised to the power of the number of divisions | M1 |
| 512 | A1 |
| stating the unit as bacteria (bacterial cells) | B1 |
| Final answer: 512 bacteria | |
| Question 12[4 marks] | |
|---|---|
| Answer or working | Marks |
| using GPE = m g h | M1 |
| substituting 250 x 9.8 x 12 | M1 |
| correct evaluation | M1 |
| 29400 J (29.4 kJ) | A1 |
| Question 13[4 marks] | |
|---|---|
| Answer or working | Marks |
| using p1 V1 = p2 V2 | M1 |
| substituting 150 x 0.80 = 400 x V2 | M1 |
| rearranging to V2 = (150 x 0.80) / 400 | M1 |
| 0.30 m^3 | A1 |
| Question 14[4 marks] | |
|---|---|
| Answer or working | Marks |
| using rate = 1 / time | M1 |
| substituting 1 / 40 | M1 |
| 0.025 | A1 |
| correct unit, s^-1 | B1 |
| Final answer: 0.025 s^-1 | |
| Question 15[5 marks] | |
|---|---|
| Answer or working | Marks |
| finding the rate at the lower light intensity, 45 / 3 = 15 bubbles per minute | M1 |
| finding the rate at the higher light intensity, 75 / 3 = 25 bubbles per minute | M1 |
| finding the increase in rate, 25 - 15 = 10 | M1 |
| (10 / 15) x 100 | M1 |
| 66.7% | A1 |
| Final answer: 66.7% increase in the rate of bubble production | |
| Question 16[5 marks] | |
|---|---|
| Answer or working | Marks |
| noble gas atoms having a full outer shell of electrons | B1 |
| stating this means the atoms do not need to gain, lose or share electrons to become stable | B1 |
| stating the noble gases are (very) unreactive | B1 |
| the noble gases existing as single (monatomic) atoms, not molecules | B1 |
| stating they are colourless gases at room temperature | B1 |
| Final answer: Full outer electron shells make noble gases unreactive; they exist as colourless, monatomic gases | |
| Question 17[5 marks] | |
|---|---|
| Answer or working | Marks |
| moles of HCl = 2.0 x (50 / 1000) | M1 |
| 0.1 mol | A1 |
| using the 2:1 mole ratio between HCl and MgCl2 from the equation | M1 |
| mass = moles x relative formula mass, 0.05 x 95 | M1 |
| 4.75 g | A1 |