What is the energy change for a system that releases100 kJ of heat to its surroundings and has 25 kJ of work done on it?

Calcium carbide (CaC2) can be made by heating calcium oxide (lime) with carbon (charcoal). CaO(s) + 3C(s) ” CaC2(s) + CO(g); ΔHo = +464.8 kJ How much heat, in joules, is absorbed in a reaction in which 2.50 mol C(s) is consumed under these conditions?  

When 1.045 g of BaO is added to 100.0 ml of water at 22.0 oC in a coffee-cup calorimeter, the temperature of the water increases to 25.7 oC. Assume that the specific heat and density of the solution is 4.184 J/g∙oC and 1.00g/ml, respectively. The heat capacity of the calorimeter is 25.0 J/oC. Calculate ΔH for the reaction. BaO(s) + H2O(l) → Ba(OH)2(aq); ΔH = __________

Air bags are activated when a severe impact causes a steel ball to compress a spring and electrically ignite a detonator cap. This causes sodium azide (NaN3) to decompose explosively according to the following reaction: 2NaN3(s) ® 2Na(s) + 3N2(g) What mass of NaN3(s) must be reacted in order to inflate an air bag to 75.0 l at STP?

Given the reaction: 2SO2(g) + O2(g) ®2SO3(g); DHo = -197.8 kJ Which statement is correct?

The heat of reaction measured using a constant volume, bomb calorimeter is equal the ______?

By early week 5 of gestation we expect to see which of the followings?

Fertilization takes place in the ……………………………………………….  of the fallopian tube as the zygote begins its development and moves toward the uterine cavity.

pregnancy failure is diagnosed when a CRL measurements is ………….. without cardiac function.

 On some continents most wood is used for fuel, but on other continents most wood is used for lumber.