When 0.876 g of cacl2 (110.98 g/mol) is added to 95.0 g of water at 22.4 °c in a ‘coffeecup’ calorimeter, the temperature of the resulting solution increases to 29.7 °c. the specific heat capacity of the solution is 4.184 j/°c·g and the heat capacity of the styrofoam cup is negligible. a) is this reaction endothermic or exothermic? how do you know? b) calculate the molar heat of solution (∆hrxn) of cacl2 in water

A) Exothermic

B) 367.6 kJ/mol

Explanation:

A) The reaction is exothermic, we know this because the temperature of the resulting solution increased.

B) We use two formulas

So first we calculate the heat Q released into the water:

Now we divide that value by the moles of CaCl₂:

in chemistry, adhesion and cohesion are attractive forces that exist between molecules. they hold the molecules together from each other. they are different in that adhesive force exists between molecules of different substance while cohesive force happens between molecules of same substance.

adhesion between water and glass causes water molecules at the edge of water and glass interface to climb up the wall in a narrow glass tube. this is called capillary action. cohesion is what gives glass its shape and causes water to form a droplet.

it would be b. 6co2 + 6h2o --> c6h12o6 + 6o2