General Science

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

What is the best description of litmus?

A acid-base indicator red in acid and blue in base
B solid-to-gas change without passing through liquid
C amount of solute relative to a specified quantity
D corrosion product formed mainly on iron/steel

Which of the following is most closely associated with common salt?

A amorphous inorganic solid commonly based on silica
B compressed natural gas, mainly methane
C sodium chloride
D reaction absorbing heat

Which statement correctly identifies gypsum?

A pure substance whose atoms have the same atomic number
B combining capacity of an atom or ion
C uncharged subatomic particle
D calcium sulfate dihydrate

Which of the following is most closely associated with carbon monoxide?

A negatively charged subatomic particle
B CO, toxic product of incomplete combustion
C anything having mass and occupying space
D chemical oxygen demand, oxygen equivalent needed for chemical oxidation of substances in water

Which of the following is most closely associated with electrolyte?

A substance releasing usable energy in combustion or another process
B small molecule that can form a polymer
C gain of electrons or decrease in oxidation state
D substance producing ions in solution or molten state

What is the best description of neutron?

A polymer produced from ethene
B solid fossil fuel formed largely from ancient plant matter
C steel containing sufficient chromium for corrosion resistance
D uncharged subatomic particle

Which statement correctly identifies period?

A pure substance whose atoms have the same atomic number
B horizontal row in the periodic table
C uncharged subatomic particle
D combining capacity of an atom or ion

Which of the following is most closely associated with atom?

A iron-based alloy containing carbon
B smallest unit of an element retaining its chemical identity
C separation based mainly on differences in boiling points
D component that dissolves the solute

Which of the following is most closely associated with non-metals?

A solid-to-gas change without passing through liquid
B elements generally lacking typical metallic properties
C polyvinyl chloride polymer
D corrosion product formed mainly on iron/steel

Which of the following is most closely associated with endothermic reaction?

A elements generally lacking typical metallic properties
B substance changing colour over a characteristic pH range
C reaction releasing heat
D reaction absorbing heat

Which of the following is most closely associated with gypsum?

A calcium sulfate dihydrate
B elements generally lacking typical metallic properties
C substance changing colour over a characteristic pH range
D reaction releasing heat

In general science, hard water refers to:

A CH4, simplest alkane and major natural-gas component
B water containing appreciable calcium or magnesium ions
C calcium sulfate dihydrate
D CO, toxic product of incomplete combustion

Which of the following is most closely associated with baking soda?

A vertical column in the periodic table
B number of protons plus neutrons
C combination of substances retaining their chemical identities
D sodium hydrogen carbonate, NaHCO3

What is the best description of mole?

A negatively charged ion
B negatively charged subatomic particle
C anything having mass and occupying space
D SI amount-of-substance unit containing Avogadro’s number of entities