Acertain chemical reaction releases 16.8/kjg of heat for each gram of reactant consumed. how can you calculate what mass of reactant will produce 800.j of heat? set the math up. but don't do any of it. just leave your answer as a math expression

The unit of 16.8 /kjg contains a mistake.

I just can help you by assuming the right units.

I will assume 16.8 kj /g. This is a rate, which means that 1 g of reactant will produce 16.8 kj of heat.

To calculate the mass of reactant that will produce 800j first you multiply by the conversion factor to obtain kj, and the you divide by the rate of heat, 16.8 kj/g

heat * conversion factor / rate

(800j) * (1kj/1000j) / (16.8 kj / g) <--- answer

Mass of reactant that will produce 800 joules can be calculated using ;

( 800 joules ) * ( 1 kilojoules / 1000 joules) / ( 16.8 kilojoules / grams)

Given that :

I gram of reactant produces  16.8 Kilojoules of heat

Express The formula to determine the mass that produces 800 joules of heat

1 gram = 16.8 Kj

x gram = 800 joules

∴ The mass of reactant that will produce 800 joules ( x gram )

= Heat produced by the unknown mass * ( 1kj / 1000j ) / conversion rate

= ( 800 joules ) * ( 1 kilojoules / 1000 joules) / ( 16.8 kilojoules / grams)

Note : ( 1kj / 1000j ) = conversion factor

Hence we can conclude that Mass of reactant that will produce 800 joules can be calculated using ;  ( 800 joules ) * ( 1 kilojoules / 1000 joules) / ( 16.8 kilojoules / grams).

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A. Exo means outside, Endo means inside, and thermic means heat!
B. Enthalpy of reaction= enthalpy of formation of products