Describe how you could use IR spectroscopy to distinguish between ethyl acetate and butyric acid. The IR spectrum of butyric acid should have a broad signal between 1650 cm-1 and 1850 cm-1. An IR spectrum of ethyl acetate will not have this signal. The IR spectrum of butyric acid should have a broad signal between 2500 cm-1 and 3600 cm-1. An IR spectrum of ethyl acetate will not have this signal. The IR spectrum of ethyl acetate should have a broad signal between 2500 cm-1 and 3600 cm-1. An IR spectrum of butyric acid will not have this signal. The IR spectrum of ethyl acetate should have a broad signal between 1650 cm-1 and 1850 cm-1. An IR spectrum of butyric acid will not have this signal.

The IR spectrum of butyric acid should have a broad signal between 2500 cm⁻¹ and 3600 cm⁻¹. An IR spectrum of ethyl acetate will not have this signal.

Explanation:

IR spectroscopy is a widely used technique in chemical identifications. In a IR spectrum, signals depend of nature of bonds in the chemical structure of the compound.

Ethyl acetate is an esther. Its principal signal is between 16500cm⁻¹ and 1850cm⁻¹ (Carboxylic compound).

Butyric acid is a carboxylic acid. Carboxylic acids have 2 principal signals: The first is between 16500cm⁻¹ and 1850cm⁻¹ (Carboxylic compound) and the second is between 2500cm⁻¹ and 3600cm⁻¹ (Due the hydrogen bonding between O-H atoms).

Thus, right answer is:

The IR spectrum of butyric acid should have a broad signal between 2500 cm⁻¹ and 3600 cm⁻¹. An IR spectrum of ethyl acetate will not have this signal.

as given the equation is

2al + 6 hcl > 2 alcl3 + 3 h2(g)

as per equation two moles of aluminum reacts with six moles of hcl to give two moles of alcl3 and three moles of hydrogen gas

given: three moles of al are present and 7 moles of hcl

for three moles of aluminum nine moles of hcl will be required

however as 7 moles of hcl are present so the limiting reagent is hcl

hcl is going to decide the number of moles of product formed

when six moles of hcl are present = 3 moles of h2 are formed

when one mole of hcl is present == 3/6 mole sof h2 will be formed

when 7 moles of hcl are present = 3 x 7/ 6 moles of h2 will be formed = 3.5 moles of h2