The person whose work led to a periodic table based on increasing atomic number was Henry Moseley.
the distance light travels in one earth year
B.
the distance light travels from the sun to the earth
C.
the distance light travels in one orbit of the moon
D.
the time it takes light to travel across the universe
Answer:
nuetrons
Explanation:
some helium atoms just a little thick and packing extra neutrons
Light shining through the less dense material.
(AHC H20(I) = -285.8 kJ/mol)
A -120.9 kJ
B-241.8 kJ
C-571.6 kJ
D-285.8 kJ
Answer:
The heat of reaction when hydrogen and oxygen combine to form water is :
C. 571.6 kJ
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