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3 years ago

What is the approximate time of death if the body temperature was 15.6°C?

Chemistry

1 answer:

WARRIOR [948]3 years ago

6 0

Answer:

This stiffening process, called Rigor Mortis, has a roughly known time of occurrence and can therefore be used to estimate time of death. In general: If the body feels warm and no rigor is present, death occurred under 3 hours before. If the body feels warm and stiff, death occurred 3-8 hours earlier.

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The expression of the theoretical yield (TY) in function of limiting reagent (LR) of a reaction is as follows: TY = ideal mole r

spin [16.1K]

Answer: The theoretical yield of acetanilide is 6.5 grams.

Explanation:

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$ .....(1)

For aniline:

Given mass of aniline = $4.50\times 10^0=4.50g$ (We know that: $10^0=1$ )

Molar mass of aniline = 93.13 g/mol

Putting values in equation 1, we get:

$\text{Moles of aniline}=\frac{4.50g}{93.13g/mol}=0.048mol$

For acetic anhydride:

To calculate the mass of acetic anhydride, we use the equation:

$\text{Density of substance}=\frac{\text{Mass of substance}}{\text{Volume of substance}}$

Volume of acetic anhydride = $(1.25\times \text{Mass of aniline})=1.25\times 4.50=5.625mL$

Density of acetic anhydride = 1.08 g/mL

Putting values in above equation:

$1.08g/mL=\frac{\text{Mass of acetic anhydride}}{5.625mL}\\\\\text{Mass of acetic anhydride}=(1.08g/mL\times 5.625mL)=6.08g$

Given mass of acetic anhydride = 6.08 g

Molar mass of acetic anhydride = 102.1 g/mol

Putting values in equation 1, we get:

$\text{Moles of acetic anhydride}=\frac{6.08g}{102.1g/mol}=0.06mol$

The chemical equation for the reaction of aniline and acetic anhydride follows:

$C_6H_5NH_2+CH_3COOCOCH_3\rightarrow C_6H_5NHCOCH_3+CH_3COOH$

By Stoichiometry of the reaction:

1 mole of aniline reacts with 1 mole of acetic anhydride

So, 0.048 moles of aniline will react with = $\frac{1}{1}\times 0.048=0.048mol$ of acetic anhydride

As, given amount of acetic anhydride is more than the required amount. So, it is considered as an excess reagent.

Thus, aniline is considered as a limiting reagent because it limits the formation of product.

By Stoichiometry of the reaction:

1 mole of aniline produces 1 mole of acetanilide

So, 0.048 moles of aniline will produce = $\frac{1}{1}\times 0.048=0.048mol$ of acetanilide

Now, calculating the theoretical yield of acetanilide by using equation 1:

Moles of acetanilide = 0.048 moles

Molar mass of acetanilide = 135.17 g/mol

Putting values in equation 1, we get:

$0.048mol=\frac{\text{Mass of acetanilide}}{135.17g/mol}\\\\\text{Mass of acetanilide}=(0.048mol\times 135.17g/mol)=6.5g$

Hence, the theoretical yield of acetanilide is 6.5 grams.

3 0

3 years ago

Which of the following is the least reactive nonmetal? A. I B. F C. Br D. Cl

tatyana61 [14]

the answer is A. I (iodine)

no worries

5 0

3 years ago

Element X consist of two isotopes with masses of 62.9 and 64.9. The relative atomic mass of the element is 63.6. What is th

koban [17]

Answer:

it is 50%

Explanation:

62.9x50=3145

64.9x50=3245

3245+3145=6390

6390/100=63.9

4 0

2 years ago

Calculate the ΔG°' for the reaction with 3 significant figures with no label for the dimension (just the number). fructose-6-pho

seraphim [82]

Answer:

ΔG° = 1747.523

Explanation:

The parameters mentioned are;

Gibbs Free energy ΔG°

Equilibrium constant Kc

Temperature T = 37 + 273 = 310 (upon conversion to kelvin temperature)

The formular relating all three parameters is given as;

ΔG° = -RTlnKc

Where; R = rate constant = 8.314 J⋅K−1⋅mol−1

Upon solving;

ΔG° = - 8.314 * 310 * ln(1.97)

ΔG° = 1747.523

6 0

3 years ago

What is the name of the polyatomic ion with the molecular formula SO32-

IceJOKER [234]

Answer:

sulfite ion SO32

Explanation:

A molecular ion is a covalently bonded set of two or more atoms, or of a metal complex, that can be considered to behave as a single unit and that has a net charge that is not zero.

8 0

2 years ago