thermochemistry Ch4 S1 Quiz 2

which of the following remains constant in close system

• energy

• mass

• temperature

• heat enthalpy

what is the change in heat enthalpy on dissolving 40 gm of NaOH in water to form 1 liter of solution knowing that temperature is raised by 10.6 $\degree$ C  [NaOH molar mass is 40gm/mol]

• -0.443 Kj

• -4.4308 Kj

• -44.308 Kj

• -44 Kj

from the first 2 equations

then the heat change of the third equation is ______ Kj/mol

• -78

• -46

• +46

• +78

For the following equation the change in heat content is ..... Kj/mol

[knowing that the heat change of H₂O is -286 ; CuCl₂ is -206 ; CuCl₂.2H₂O is -808 Kj]

• -1586

• +30

• -110

• -30

using the following and given bond energies , the  $\Delta$  H of this reaction is ......... KJ/mol

• -560

• -124

• +486

• +5496

the heat change of the 2nd equation is ......... Kj

• -66

• -33

• +33

• +66

The sand in desert is considered ..... system

• closed

• opened

• isolated

• no correct asnwer

What is the  $\Delta$ H of the following equation [knowing that heat content of substances are H2O=-285.5; CO2=-393.5; CH3OH=-238 Kj/mol]

• -726.5

• -441

• -1202.5

• -60.5

if you know that the respiration process is the reverse process of photosynthesis, then the respiration process si considered ............

• Endothermic

• Exothermic

• Both

• Neither endothermic nor exothermic

if the quantity of heat produced from combustion of 1.3 gm of glucose ( its molar mass is 180 gm/mol) cause the increase of amount of pure water by 24.3 $\degree$ C .
Knowing that the standard ehat fo combustion of glucose is -2816 KJ/mol, the mass of water is ........ gm

• 63.18

• 24.3

• 0.194

• 31.59