Yes, they are called periods. Pls do you need a confirmation on this and if not what is the question?
Enzymes offer a faster pathway for the reaction to happen, so they lower the activation energy necessary for the reaction to happen. The result is that the reaction will happen faster
The reaction is low b/c of the tempature. that's why.
Answer is: 13181,7 kJ of energy <span>is released when 10.5 moles of acetylene is burned.
</span>Balanced chemical reaction: C₂H₂ + 5/2O₂ → 2CO₂ + H₂O.
<span>ΔHrxn = sum of
ΔHf (products of reaction) - sum of ΔHf (reactants).</span><span>
Or ΔHrxn = ∑ΔHf (products of reaction)
- ∑ΔHf (reactants).
ΔHrxn - enthalpy change of chemical reaction.
<span>ΔHf - enthalpy of formation of reactants or
products.
</span></span>ΔHrxn = (2·(-393,5) + (-241,8)) - 226,6 · kJ/mol.
ΔHrxn = -1255,4 kJ/mol.
Make proportion: 1 mol (C₂H₂) : -1255,4 kJ = 10,5 mol(C₂H₂) : Q.
Q = 13181,7 kJ.
First, draw the 2-hexene. Th is is a molecule of six carbons with a double bond in the second carbon:
CH3 - CH = CH2 - CH2 - CH2 - CH3
Secong, put one Br on the second carbon and one Br on the third carbon:
CH3 - CBr = CBr - CH2 - CH2 - CH3
Third, cis means that the two Br are placed in opposed positions, this is drawn with one Br up and the other down. So, you need to represent the position of the Br in the space:
H Br H H H
| | | | |
H - C - C = C - C - C - C - H
| | | | |
H Br H H H
The important fact to realize is that the two Br are in opposed sides of the molecule.