Answer:
Qm = -55.8Kj/mole
Explanation:
NaOH(aq) + HNO₃(aq) => NaNO₃(aq) + H₂O(l)
Qm = (mc∆T)water /moles acid
Given => 100ml(0.300M) NaOH(aq) + 100ml(0.300M)HNO₃(aq)
=> 0.03mole NaOH(aq) + 0.03mole HNO₃(aq)
=> 0.03mole NaNO₃(aq) + 0.03mole H₂O(l)
ΔH⁰rxn = [(200ml)(1.00cal/g∙°C)(37 – 35)°C]water / 0.03mole HNO₃
= 13,333 cal/mole x 4.184J/cal = 55,787J/mol = 55.8Kj/mole (exothermic)*
Heat of reactions comes from formation of H-Oxy bonds on formation of water of reaction and heats the 200ml of solvent water from 35⁰C to 37⁰C.
The statement is false because endothermic reactions have a positive enthalpy change, because heat is being added to the system because it requires more energy to react
Answer:
340g
Explanation:
Lithium oxide or Li2O is an inorganic compound made of two lithiums and one oxygen molecules. Lithium molecular mass is 6.94g/mol while oxygen molecular mass is 16g/mol. The molecular mass of Li2O will be:
2* 6.94g/mol + 1*16g/mol= 29.88g/mol
Out of 1 mol lithium oxide (29.88g), there is 1 mol of oxygen(16g). Then, out of 635g lithium oxide the number of oxygen will be: 635g * (16g/29.88g)= 340g
The answer is E.solution. I hope it helps. Please Brainly Me! It is the thing with the crown next to the stars.
