Answer to Question #129951 in General Chemistry for Mary

Question

Hi,
When a solution of LiOH is neutralized by nitric acid, the solution gets hot.

Calculate the mass of the combined solution (in g).

Temperature change of the solution = 16.6 K
Heat change of the solution = 4530 J
Specific heat capacity of the solution = 4.18 J/g·K

Please Give your answer to three significant figures. Thanks

Answer 1

$The\ balanced\ equation\ is\newline LiOH\ +HNO_3\ \to LiNO_3\ +H_2O$

$In\ a \ neutralization \ reaction\ when \ a \ base \ or \ an \ acid\ is\newline added\ to\ a n\ aqueous\ solution \ of an\ acid\ or\ a \ base\newline respectively\ the \ solution\ temperature\ increases.$

$The\ following\ formula \ is\ used\ to\ calculated\ produced \newline heat\$

$q=mc_s\Delta T\ \ where,\newline \Delta T\ is \ the\ temperature\ change\ =16.6K\newline m\ = mass\ of\ substance\ in \ grams \ =??\newline c_s=specific\ heat\ =4.18J/gK\newline q=heat\ produced\ =4530J$

$Substituting \ values\ to \ the\ equation\ we\ get,$

$4530=m\ *\ 4.18\ *16.6\newline4530=69.388\ m\newline m=\dfrac{4530}{69.388}$

$m=65.2g\$