Using the information in the table to the right, calculate the average atomic mass of strontium. Report to two decimal places. 45
amu
A 3 column table with 4 rows titled Strontium. Column 1 is labeled Isotope with entries Upper S r-84, Upper S r-86, Upper S r-87, Upper S r-88. Column 2 is labeled Mass (a m u) with entries 83.913428, 85.909273, 86.908902, 87.905625. Column 3 is labeled Abundance (percent) with entries 0.56, 9.86, 7, 82.58.

56 moles of   lieter in chemistry

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.