Answer:
C
Explanation:
If the enthalpy change (i.e. Δ<em>H</em>) of a reaction is negative, then the reaction releases heat and is hence exothermic.
Hence, our answer is C.
Conversely, if Δ<em>H</em> is positive, the reaction absorbs heat and is endothermic.
Δ<em>H</em> tells us nothing about the speed of the reaction.
While Δ<em>H</em> influences free-energy change (Δ<em>G</em> = Δ<em>H</em> - <em>T</em>Δ<em>S</em>), we cannot predict the sign of Δ<em>G</em> given only Δ<em>H </em>(recall that a reaction is spontaneous if Δ<em>G</em> < 0).
Answer:
CHO2- ion
Explanation:
We have the lewis structure of a formate-ion here
This is CHO2-.
The carbon atom is the central atom in the structure. It's the least electronegative atom (C). Carbon has 4 valence electrons. Oxygen has 6 valence electrons.
The carbon will bind with 1 hydrogen atom, this will form 1 single bond, because hydrogen has 1 valence electron.
The carbon will bind with oxygen via a double bond.
Since carbon has only 4 valence electrons, it can only form 1 bond with the other oxygen atom.
There will formed 1 double bond between C and O and 1 single bond between C and O resulting in a negative charged O-atom.
This means there are two resonance structures. for the CHO2- ion
I think its most likely to be A,
What are the options? based on the volume it can differ but in general pipettes and graduated cylinder are the best. <span />