General Science

Which statement correctly identifies solvent?

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 component that dissolves the solute

What is the best description of CNG?

A substance donating H+ in Brønsted-Lowry theory
B loss of electrons or increase in oxidation state
C compressed natural gas, mainly methane
D rapid reaction with an oxidant commonly releasing heat

In general science, soap refers to:

A ethanoic acid, CH3COOH
B material supplying plant nutrients
C gas absorbing and emitting infrared radiation
D salts of higher fatty acids

Which statement correctly identifies CNG?

A compressed natural gas, mainly methane
B energy barrier associated with a reaction pathway
C fossil fuel consisting mainly of methane
D fluoropolymer known for chemical resistance and low friction

Which of the following is most closely associated with cation?

A positively charged ion
B atom or group of atoms carrying net electric charge
C mass of one mole of a substance
D two or more atoms chemically bonded

In general science, isotope refers to:

A CO, toxic product of incomplete combustion
B atoms of the same element with different neutron numbers
C CH4, simplest alkane and major natural-gas component
D calcium sulfate dihydrate

In general science, mole refers to:

A SI amount-of-substance unit containing Avogadro’s number of entities
B ionic compound of cations and anions
C energy barrier associated with a reaction pathway
D elements generally showing conductivity, malleability and ductility

In general science, alloy refers to:

A mixture or solid solution of metals or metal with another element
B fertiliser supplying nitrogen, phosphorus and potassium
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, base refers to:

A substance producing ions in solution or molten state
B mixture or solid solution of metals or metal with another element
C substance dissolved in a solution
D substance accepting H+ or producing OH− in water

In general science, pesticide refers to:

A Group 18 elements with very low reactivity
B substance used to control pests
C substance accepting H+ or producing OH− in water
D atom or group of atoms carrying net electric charge

What is the best description of molecule?

A substance accepting H+ or producing OH− in water
B two or more atoms chemically bonded
C substance releasing usable energy in combustion or another process
D gain of electrons or decrease in oxidation state

What is the best description of anion?

A CH4, simplest alkane and major natural-gas component
B negatively charged ion
C water containing appreciable calcium or magnesium ions
D calcium sulfate dihydrate

Which statement correctly identifies rust prevention?

A CO2, important greenhouse gas
B methods such as painting, galvanising or alloying that reduce corrosion
C mass of one mole of a substance
D two or more atoms chemically bonded

What is the best description of sublimation?

A combining capacity of an atom or ion
B solid-to-gas change without passing through liquid
C ionic compound of cations and anions
D elements generally showing conductivity, malleability and ductility

Which statement correctly identifies valency?

A chemical oxygen demand, oxygen equivalent needed for chemical oxidation of substances in water
B combining capacity of an atom or ion
C nitrogen fertiliser, CO(NH2)2
D anything having mass and occupying space

Which statement correctly identifies non-metals?

A elements generally lacking typical metallic properties
B measure related to hydrogen-ion activity/concentration
C reaction involving oxidation and reduction together
D solid fossil fuel formed largely from ancient plant matter

What is the best description of atomic number?

A number of protons in the nucleus
B mixture or solid solution of metals or metal with another element
C substance producing ions in solution or molten state
D large molecule made of repeating structural units

Which of the following is most closely associated with pesticide?

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

What is the best description of hard water?

A water containing appreciable calcium or magnesium ions
B steel containing sufficient chromium for corrosion resistance
C separation of insoluble solids from a fluid using a filter
D homogeneous mixture of solute and solvent

Which of the following is most closely associated with catalyst?

A substance changing reaction rate without being consumed overall
B uncharged subatomic particle
C combining capacity of an atom or ion
D elements generally showing conductivity, malleability and ductility

Which statement correctly identifies coal?

A arrangement of elements by atomic number and recurring properties
B solid fossil fuel formed largely from ancient plant matter
C elements generally lacking typical metallic properties
D substance changing colour over a characteristic pH range

Which statement correctly identifies urea?

A mixture or solid solution of metals or metal with another element
B large molecule made of repeating structural units
C substance producing ions in solution or molten state
D nitrogen fertiliser, CO(NH2)2

What is the best description of combustion?

A number of protons in the nucleus
B rapid reaction with an oxidant commonly releasing heat
C methods such as painting, galvanising or alloying that reduce corrosion
D pure substance formed by chemical combination of elements in fixed proportions

What is the best description of cation?

A temperature at which solid and liquid coexist at specified pressure
B synthetic surfactant used for cleaning
C positively charged ion
D calcium hydroxide

In general science, sublimation refers to:

A solid-to-gas change without passing through liquid
B liquefied petroleum gas, mainly propane and butane
C reaction releasing heat
D fluoropolymer known for chemical resistance and low friction