WorksheetsEOT COVARAGE
Total questions: 8
Worksheet time: 8mins
Explain the law of conservation of mass?
mass neither be created nor be destroyed The overall mass of the reactant is equal to the over all mass of the products.
mass is create and destroyed. the overall mass of the reactant is equal to the over all mass of products
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Describe the purpose of coefficient in the chemical equations?
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it describes the total number of reactant in the chemical equation
Coefficient describes the number of units of each reactant or products in the chemical equations.
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How can you tell whether a chemical equation is balanced or not balanced?
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an equation is balanced number of atoms of one side is not same in the equation.
An equation is balanced if the number of atoms of each elements of the same on the both side of the equation
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Balance this equation-NaOH(aq)+CaBr2(s)------->Ca(OH)2(s) +NaBr(aq)
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Ca(OH)2(s)+2NaBr(aq)
CaOH2 +2Na Br
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What happens in a combustion reaction?
A substance combines with oxygen to produce energy
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it is an insoluble compound that comes out of solution during the type of reaction
compare and contrast oxidation and reduction
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oxidation involves loss of electron and reductions involves gain of electron.
reduction involves loss of electron and oxidation is the gain of electron.
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Consider the following reaction Ba(NO3)2(aq)+K2SO4(aq)---->BaSO4(s) +2KMNO3(aq).Which substance is the precipitate? What type of reaction is this?
BaSO4, Double displacement reaction
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KMNO4, Combustion reaction
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Why is a log fire is considered to be an exothermic reaction?
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The reaction of the oxygen in the air with the carbon compounds in the log releases heat and light. the release of thermal energy means the reaction is exothermic
the chemical reaction that release energy and that required break the bond n the reaction
