General Science

Which statement correctly identifies slaked lime?

A calcium hydroxide
B substance donating H+ in Brønsted-Lowry theory
C atoms of the same element with different neutron numbers
D horizontal row in the periodic table

Which statement correctly identifies rust?

A CO, toxic product of incomplete combustion
B two or more atoms chemically bonded
C corrosion product formed mainly on iron/steel
D mass of one mole of a substance

Which of the following is most closely associated with CNG?

A chemical decomposition driven by electric current
B synthetic surfactant used for cleaning
C compressed natural gas, mainly methane
D temperature at which solid and liquid coexist at specified pressure

Which statement correctly identifies filtration?

A reaction between acid and base forming salt and usually water
B substance changing reaction rate without being consumed overall
C separation of insoluble solids from a fluid using a filter
D Group 17 elements

Which statement correctly identifies steel?

A methods such as painting, galvanising or alloying that reduce corrosion
B iron-based alloy containing carbon
C aqueous solution containing acetic acid
D O3, allotrope of oxygen

Which of the following is most closely associated with methane?

A temperature at which vapour pressure equals surrounding pressure
B CH4, simplest alkane and major natural-gas component
C salts of higher fatty acids
D coating iron or steel with zinc

What is the best description of indicator?

A coating iron or steel with zinc
B temperature at which vapour pressure equals surrounding pressure
C fluoropolymer known for chemical resistance and low friction
D substance changing colour over a characteristic pH range

In general science, reduction refers to:

A fertiliser supplying nitrogen, phosphorus and potassium
B gain of electrons or decrease in oxidation state
C biochemical oxygen demand, oxygen consumed by microbes decomposing organic matter in water
D pure substance whose atoms have the same atomic number

In general science, distillation refers to:

A measure related to hydrogen-ion activity/concentration
B solid fossil fuel formed largely from ancient plant matter
C separation based mainly on differences in boiling points
D reaction involving oxidation and reduction together

What is the best description of period?

A smallest unit of an element retaining its chemical identity
B substance used to control pests
C horizontal row in the periodic table
D CO2, important greenhouse gas

Which of the following is most closely associated with evaporation?

A component that dissolves the solute
B substance producing ions in solution or molten state
C surface vaporisation below boiling point
D mixture or solid solution of metals or metal with another element

Which of the following is most closely associated with atomic number?

A NH3, basic nitrogen compound used in fertilisers
B number of protons in the nucleus
C calcium oxide
D acidic precipitation associated mainly with sulfur and nitrogen oxides

What is the best description of petroleum?

A vertical column in the periodic table
B number of protons plus neutrons
C elements showing intermediate metal/non-metal properties
D liquid hydrocarbon mixture from geological deposits

What is the best description of ion?

A component that dissolves the solute
B atom or group of atoms carrying net electric charge
C sodium carbonate decahydrate
D separation based mainly on differences in boiling points

Which statement correctly identifies metals?

A energy barrier associated with a reaction pathway
B Group 17 elements
C elements generally showing conductivity, malleability and ductility
D ionic compound of cations and anions

What is the best description of ethanol?

A an alcohol used in sanitizers, solvents and fuels
B measure related to hydrogen-ion activity/concentration
C Group 1 metals other than hydrogen
D reaction involving oxidation and reduction together

Which statement correctly identifies LPG?

A large molecule made of repeating structural units
B acid-base indicator red in acid and blue in base
C liquefied petroleum gas, mainly propane and butane
D reaction absorbing heat

In general science, methane refers to:

A CH4, simplest alkane and major natural-gas component
B small molecule that can form a polymer
C separation based mainly on differences in boiling points
D iron-based alloy containing carbon

What is the best description of acid?

A gain of electrons or decrease in oxidation state
B substance accepting H+ or producing OH− in water
C substance releasing usable energy in combustion or another process
D substance donating H+ in Brønsted-Lowry theory

Which of the following is most closely associated with isotope?

A pure substance formed by chemical combination of elements in fixed proportions
B O3, allotrope of oxygen
C atoms of the same element with different neutron numbers
D methods such as painting, galvanising or alloying that reduce corrosion

What is the best description of catalyst?

A calcium hypochlorite-based bleaching/disinfecting material
B ethanoic acid, CH3COOH
C gas absorbing and emitting infrared radiation
D substance changing reaction rate without being consumed overall

In general science, salt refers to:

A component that dissolves the solute
B ionic compound of cations and anions
C aqueous solution containing acetic acid
D sodium carbonate decahydrate

Which of the following is most closely associated with BOD?

A combining capacity of an atom or ion
B biochemical oxygen demand, oxygen consumed by microbes decomposing organic matter in water
C elements generally showing conductivity, malleability and ductility
D uncharged subatomic particle

In general science, concentration refers to:

A amount of solute relative to a specified quantity
B nitrogen fertiliser, CO(NH2)2
C calcium hydroxide
D synthetic surfactant used for cleaning

Which statement correctly identifies mole?

A SI amount-of-substance unit containing Avogadro’s number of entities
B horizontal row in the periodic table
C atoms of the same element with different neutron numbers
D substance donating H+ in Brønsted-Lowry theory