What is the most probable role of zinc in the Barbier reaction based on the paper by Petrier and Luche? Group of answer choices It donates two electrons to the alkyl halide (one to the alkyl group and one to the halogen) and forms an intermediate that behaves like a carbanion. This organozinc intermediate can then attack the carbonyl, just like in a Grignard reaction. It probably provides a surface for the carbonyl and alkyl halide to react via a free radical type reaction. It provides a positive charge that stabilizes the product.

The energy (heat) required to convert 52.0 g of ice at –10.0°C to steam at 100°C is 157.8 kJ

Explanation:

Using this formular, q = [mCpΔT] and = [nΔHfusion]

The energy that is needed in the different physical changes is thus:

The heat needed to raise the ice temperature from -10.0°C to 0°C is given as as:

q = [mCpΔT]

q = 52.0 x 2.09 x 10

q = 1.09 kJ

While from 0°C to 100°C is calculated as:

q = [mCpΔT]

q = 52.0 x 4.18 x 100

q = 21.74 kJ

And for fusion at 0°C is called Heat of fusion and would be given as:

q = n ΔHfusion

q = 52.0 / 18.02 x 6.02

q = 17.38 kJ

And that required for vaporization at 100°C is called Heat of vaporization and it's given as:

q = n ΔHvaporization

q = 52.0 / 18.02 x 40.7

q = 117.45 kJ

Add up all the energy gives 157.8 kJ