Calcium carbonate thermally decomposes to produce calcium oxide and carbon dioxide. After 90 seconds, the 10g of calcium carbonate has decreased to 8g.
What is the rate of reaction?

1/45 or 0.0222 g/s

Explanation:

rate of reaction = quantity of reactant used/time taken

                            = (10-8)/90

                            = 1/45 or 0.0222 g/s

p.s add as brainliest

the enthalpy of formation of water is given as -285.8kj/mol, which states that the enthalpy of formation is negative.

negative enthalpy of formation indicates that the heat is released during the reaction process. the heat is released from reaction to the surroundings the enthalpy is expressed with a negative sign with the energy given out in the reaction process.

the formation of water takes place by giving out heat which is -285.8 kj/mol.

5.6⋅10−^19  j

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