Answer:
The balanced equation is:
2 HNO3 + Mg ---> Mg(NO3)2 + H2
From the equation, we can see that we need twice the moles of HNO3 than the moles of Mg
Moles of Mg:
Molar mass of Mg = 24 g/mol
Moles = Given mass / Molar Mass
Moles of Mg = 4.47 / 24 = 0.18 moles (approx)
Hence, 2(moles of Mg) = 0.36 moles of HNO3 will be consumed
Number of moles of HNO3 after the reaction is finished is the number of unreacted moles of HNO3
Unreacted moles of HNO3 = Total Moles - Moles consumed
Unreacted moles of HNO3 = 0.64 moles (approx)
Since we approximated the value of moles of Mg, the value of remaining moles of HNO3 will also be approximate
From the given options, we can see that 0.632 moles is the closest value to our answer
Therefore, 0.632 moles will remain after the reaction
Answer : The resonance structure of
is shown below.
Explanation :
Resonance structure : It is defined as when more than one Lewis structure can be drawn, the molecule or ion is said to have resonance.
Resonance is the concept where electrons (bonds) are delocalized over three or more atoms which cannot be depicted with one simple Lewis structure.
First we have to draw Lewis-dot structure.
Lewis-dot structure : It shows the bonding between the atoms of a molecule and it also shows the unpaired electrons present in the molecule.
In the Lewis-dot structure the valance electrons are shown by 'dot'.
The given molecule is, 
As we know that sulfur has '6' valence electrons, carbon has '6' valence electrons and nitrogen has '5' valence electron.
Therefore, the total number of valence electrons in
= 6 + 4 + 5 = 15
According to Lewis-dot structure, there are 7 number of bonding electrons and 8 number of non-bonding electrons.
In SCN, carbon atom is the central atom and sulfur and nitrogen are the neighboring atoms.
The resonance structure of
is shown below.
Answer:
this option is correct the amount of heat required to turn a mole of a solid into a liquid
Explanation:
The standard entropy change of a reaction has a positive value. This reaction results in an increase in entropy.
Positive entropy means the system has increased its degree of disorderness.
The wave length of light. This determinds the color/type of light.