How many grams of Br are in 345g of CaBr2?

276g of Br are present

Explanation:

To solve this question we need to find the moles of CaBr2 using its molar mass -CaBr2: 199.89g/mol-. As 1 mole of CaBr2 contains 2 moles of Br we can find the moles of Br and its mass:

Moles CaBr2:

345g * (1mol/199.89g) = 1.7259 moles CaBr2

Moles Br:

1.7259 moles CaBr2 * (2mol Br / 1mol CaBr2) = 3.4519 moles Br

Mass Br -Molar mass: 79.904g/mol-

3.4519 moles Br * (79.904g/mol) = 276g of Br are present

h let me think

a. energy is absorbed in the reaction.

if in a given reaction the energy of products is greater than the energy of reactants it means that reaction is endothermic and during the reaction, the energy is absorbed by reactants. in an endothermic reaction, the products have more stored chemical energy than the reactants. and in this reaction the reactants are more stable than products before the compounds with less energy are always more stable.