The enthalpy change for an exothermic reaction is negative because heat is being released, so that takes out two of the responses. Since energy is being released into the surroundings due to the exothermic reaction, the potential energy of the products is lower than that of the reactants. Energy is being put in to make the reaction occur, but then that energy is all being released into the surroundings thus a lower potential energy level for the products
The moles which were measured out is calculated using the following formula
moles = mass/molar mass
molar mass of CuBr2.4H20 = 63.5 Cu + ( 2 x79.9) br + ( 18 x4_) h20 = 295.3 g/mol
moles is therefore= 5.2 g/ 295.3 g/mol= 0.0176 moles
A)2nd period - Li, Be, B,C,N,O,F,Ne
b)Metalls of the 2nd period are Li,Be
I don't know what model you're referring to so I can't answer the question. However, upon researching, I found a similar problem. I posted it as an attached picture. Looking at the model, the amount of grams a herbivore eat each day corresponds to the arrow pointing inwards. Since the label says 4.0 g,
<em>the answer is 4 g per day</em>.
