Chemical Reactions and Equations – Chapter 1 Review

50 fill-in-the-blank flashcards covering key terms, reactions, definitions, and everyday applications from Chapter 1: Chemical Reactions and Equations.

A change in colour, evolution of gas, change in state or change in temperature indicates that a __ has occurred.

chemical reaction

The word-equation for burning magnesium is __ + Oxygen → Magnesium oxide.

Magnesium

Using symbols, burning magnesium is written as __ + O2 → MgO.

Mg

The equation Zn + H2SO4 → ZnSO4 + H2 is already __.

balanced

Balancing equations is necessary to satisfy the law of __ of mass.

conservation

The symbol (g) placed after a formula denotes the __ state.

gaseous

In state symbols, (s), (l) and (aq) stand for solid, liquid and __ respectively.

aqueous

Combining CaO with H2O forms Ca(OH)2 and releases heat; this is a __ reaction.

combination

Reactions that release heat along with products are called __ reactions.

exothermic

Burning natural gas is represented by CH4 + 2O2 → CO2 + 2H2O and is __ in nature.

exothermic

During respiration, __ combines with oxygen to release energy, CO2 and H2O.

glucose

A reaction in which a single reactant splits into simpler products is called a __ reaction.

decomposition

Heating CaCO3 produces CaO + CO2; this is a __ decomposition reaction.

thermal

Electrolysis of water produces hydrogen and oxygen in a __ volume ratio.

2:1

Sunlight decomposes AgCl to Ag + Cl2 in a __ decomposition.

photolytic (light-induced)

Reactions that absorb energy from surroundings are termed __.

endothermic

In Fe + CuSO4 → FeSO4 + Cu, iron __ copper from its compound.

displaces

A more reactive metal displaces a __ reactive metal from its compound.

less

Na2SO4 + BaCl2 → BaSO4 + 2NaCl is a __ displacement reaction.

double

An insoluble solid formed during a reaction in solution is called a __.

precipitate

Simultaneous oxidation and reduction in one reaction is known as a __ reaction.

redox

Oxidation is defined as the __ of oxygen or loss of hydrogen.

gain

Reduction is the loss of oxygen or the __ of hydrogen.

gain

In CuO + H2 → Cu + H2O, CuO is __ and hydrogen is oxidised.

reduced

When a metal is attacked by moisture or acids it undergoes __.

corrosion

Oxidation of fats or oils producing bad smell and taste is called __.

rancidity

Snack manufacturers flush potato-chip bags with __ to slow oxidation.

nitrogen

A balanced equation has equal numbers of __ of each element on both sides.

atoms

Using successive small trials to balance equations is called the __ method.

hit-and-trial

Conditions like temperature or catalysts are written __ the reaction arrow.

above and/or below

The equation 3Fe + 4H2O(g) → Fe3O4 + 4H2(g) shows water in the form of __.

steam

Precipitation reactions are a subtype of __ displacement reactions.

double

Decomposition reactions can be driven by heat, light, or __.

electricity

During electrolysis of water, the greater volume of gas collected is __.

hydrogen

CaO + H2O gives Ca(OH)2, also known as __ lime.

slaked

Slow conversion of Ca(OH)2 to CaCO3 on walls produces a shiny coat of __.

calcium carbonate

The chemical formula for marble is __.

CaCO3

Burning magnesium ribbon to form MgO is an __ combination reaction.

exothermic

According to the law of conservation of mass, mass can neither be __ nor destroyed.

created

In ZnO + C → Zn + CO, carbon is oxidised while __ is reduced.

ZnO