Integrated Science Exam April 2025

Which of the following relation represents the carbon content proportions in equal mass samples of coal, natural gas and petroleum?

• a

• b

• c

• d

Hemoglobin combine with CO ................ times its combination with oxygen

• 20

• 210

• 102

• 201

Aluminium is extracted from bauxite using .................. energy, while iron is extracted from hematite using ................. energy

• thermal / electric

• light / thermal

• electric / thermal

• thermal / light

All of the following apply to carbon monoxide, except ..................

• it destroy red blood cells

• it is an oxidizing agent for hematite ore

• it is produced by incomplete combustion of fuels

• it is colourless, odourless and tasteless gas

Which of the following is required to provide a safe environment to avoid chemical leakage?

• treatment – burial in special burials

• treatment – recycling

• temporary storage – burial in special burials

• temporary storage – recycling

What is the main barrier to use renewable energy on a large scale?

• limited sources

• difficulty transporting it from one place to another

• its production changes with the weather conditions

• dependence on fossil fuel

Study the following diagram: ( X ) Enzymes ( Y ) Ethanol

• ( X ) : cellulose , ( Y ) : sugar , and this process aims to obtain an efficient and sustainable biofuel

• ( X ) : sugar , ( Y ) : cellulose , and this process aims to obtain an efficient and sustainable biofuel

• ( X ) : fats , ( Y ) : cellulose , and this process aims to obtain biodiesel

• ( X ) : cellulose , ( Y ) : fats , and this process aims to obtain biodiesel

Biomass is ................

• the wet material of plants only

• the material of volcanoes

• the material of organic waste

• the dry material of plant and animal

During pyrolysis of organic wastes, the products are in the form of ............

• low-density gases and liquids only

• only gases and solids

• solids, high-density gases and liquids

• solids, low-density gases and liquids

Producing half ton of aluminium from raw materials requires 7500 kWh while recycling one ton of aluminium requires only 750 kWh, the energy saved when recycling 3 tons of aluminium equals ............

• 22500 kWh

• 45000 kWh

• 2250 kWh

• 42750 kWh