General Science

What is the best description of compound?

A substance donating H+ in Brønsted-Lowry theory
B pure substance formed by chemical combination of elements in fixed proportions
C atoms of the same element with different neutron numbers
D horizontal row in the periodic table

In general science, BOD refers to:

A smallest unit of an element retaining its chemical identity
B atoms of the same element with different neutron numbers
C biochemical oxygen demand, oxygen consumed by microbes decomposing organic matter in water
D substance used to control pests

In general science, rust refers to:

A arrangement of elements by atomic number and recurring properties
B pure substance formed by chemical combination of elements in fixed proportions
C corrosion product formed mainly on iron/steel
D number of protons in the nucleus

In general science, catalyst refers to:

A atoms of the same element with different neutron numbers
B substance used to control pests
C smallest unit of an element retaining its chemical identity
D substance changing reaction rate without being consumed overall

What is the best description of monomer?

A substance changing reaction rate without being consumed overall
B small molecule that can form a polymer
C synthetic polyamide polymer
D liquid hydrocarbon mixture from geological deposits

What is the best description of detergent?

A calcium hydroxide
B temperature at which vapour pressure equals surrounding pressure
C salts of higher fatty acids
D synthetic surfactant used for cleaning

Which statement correctly identifies petroleum?

A reaction between acid and base forming salt and usually water
B Group 17 elements
C liquid hydrocarbon mixture from geological deposits
D substance changing reaction rate without being consumed overall

In general science, bleaching powder refers to:

A pure substance formed by chemical combination of elements in fixed proportions
B arrangement of elements by atomic number and recurring properties
C number of protons in the nucleus
D calcium hypochlorite-based bleaching/disinfecting material

What is the best description of proton?

A positively charged subatomic particle
B reaction absorbing heat
C acid-base indicator red in acid and blue in base
D compressed natural gas, mainly methane

In general science, mass number refers to:

A synthetic surfactant used for cleaning
B number of protons plus neutrons
C nitrogen fertiliser, CO(NH2)2
D calcium hydroxide

What is the best description of distillation?

A atom or group of atoms carrying net electric charge
B Group 18 elements with very low reactivity
C two or more atoms chemically bonded
D separation based mainly on differences in boiling points

Which of the following is most closely associated with coal?

A reaction absorbing heat
B large molecule made of repeating structural units
C solid fossil fuel formed largely from ancient plant matter
D mixture or solid solution of metals or metal with another element

Which statement correctly identifies activation energy?

A mass of one mole of a substance
B two or more atoms chemically bonded
C energy barrier associated with a reaction pathway
D CO, toxic product of incomplete combustion

Which of the following is most closely associated with anion?

A horizontal row in the periodic table
B number of protons plus neutrons
C negatively charged ion
D combination of substances retaining their chemical identities

In general science, melting point refers to:

A temperature at which solid and liquid coexist at specified pressure
B amorphous inorganic solid commonly based on silica
C substance dissolved in a solution
D chemical decomposition driven by electric current

Which of the following is most closely associated with electron?

A calcium hypochlorite-based bleaching/disinfecting material
B homogeneous mixture of solute and solvent
C negatively charged subatomic particle
D ethanoic acid, CH3COOH

Which statement correctly identifies reduction?

A gain of electrons or decrease in oxidation state
B an alcohol used in sanitizers, solvents and fuels
C calcium sulfate hemihydrate
D CO2, important greenhouse gas

Which statement correctly identifies corrosion?

A combination of substances retaining their chemical identities
B number of protons plus neutrons
C chemical/electrochemical deterioration of a material
D material supplying plant nutrients

In general science, solvent refers to:

A component that dissolves the solute
B separation of insoluble solids from a fluid using a filter
C calcium sulfate hemihydrate
D amount of solute relative to a specified quantity

Which of the following is most closely associated with plaster of Paris?

A calcium sulfate hemihydrate
B horizontal row in the periodic table
C loss of electrons or increase in oxidation state
D substance donating H+ in Brønsted-Lowry theory

In general science, molecule refers to:

A steel containing sufficient chromium for corrosion resistance
B two or more atoms chemically bonded
C separation of insoluble solids from a fluid using a filter
D polymer produced from ethene

Which statement correctly identifies acetic acid?

A gain of electrons or decrease in oxidation state
B substance releasing usable energy in combustion or another process
C ethanoic acid, CH3COOH
D substance accepting H+ or producing OH− in water

What is the best description of PVC?

A polyvinyl chloride polymer
B compressed natural gas, mainly methane
C mixture or solid solution of metals or metal with another element
D substance producing ions in solution or molten state

What is the best description of alloy?

A mixture or solid solution of metals or metal with another element
B temperature at which solid and liquid coexist at specified pressure
C calcium hydroxide
D synthetic surfactant used for cleaning

In general science, matter refers to:

A elements generally lacking typical metallic properties
B anything having mass and occupying space
C reaction releasing heat
D substance changing colour over a characteristic pH range