Answer:
The heat of reaction when hydrogen and oxygen combine to form water is :
<u>C. 571.6 kJ</u>
Explanation:
Enthalpy Change = The enthalpy change for the formation of 1 mole of the substance from their standard state is called the enthalpy of formation.
This is intensive quantity as it is fixed for 1 mole .
Intensive properties = Those properties which are independent on the amount of the substance are intensive properties.
The value of these quantities does not get halve if you divide the substance into two equal parts. example , density, refractive index.
However , the enthalpy of reaction is extensive. Because on increasing the amount the value of the enthalpy also get doubles
Hence for this reaction :
Its value is -285.8 kJ for 1 mole
And here two moles are present . so the value of molar enthalpy is:
-285.8 x 2 = -571.6 kJ
Cooling a substance causes molecules to slow down and get slightly closer together, occupying a smaller volume that results in an increase in density. ... Cold water is more dense and will sink in room-temperature water.
The relationships between molecules atoms and a grain of sugar is the combination of atoms to molecules and the combination of molecules to a compound.
<u>Explanation:</u>
Atom is the foreground to the existence of matter and matter is just another huge combination of atoms. The presence of neutrons, protons and electrons are the important structures of atoms and these atoms are merged to build a molecule.
The relationships between molecules atoms and a grain of sugar is the combination of atoms to molecules and the combination of molecules to a compound.
Molecules are brought together with positive and negative parts of protons and electrons to form bonds and compounds. And compounds come up with elements which connects all these atoms.
Answer:
yes the answer is true because heat changes duriing epalthy change
