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3 years ago

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Chemistry

1 answer:

shtirl [24]3 years ago

7 0

Answer:

A (Hypothesis) is scientific knowledge published through direct observation and remains constant scientific knowledge can change when scientists (generate hypothesis)

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1. Show the mechanism for the main product for the monochlorination of 2-methylbutane. List all other products.

Bad White [126]

Answer:

See explanation below

Explanation:

First, we need to understand that the monochlorination of an alkane like this one, involves substitution of one of the atoms of hydrogen of the molecule for an atom of chlorine.

This reaction takes place when the alkane reacts with Cl₂ in presence of light or heat.

When this happens, the first step involves the breaking of the double bond of the chlorine to form the ion Cl⁻.

The next step involves the substraction of the hydrogen of the molecule by the Chlorine. This will leave the alkane with a lone pair available for reaction.

The third step, the alkane with the lone pair of electron substract a chlorine for the beggining and form the mono chlorinated product.

The final step involves forming the remaining products with the remaining reagents there.

In the picture attached you have the mechanism and product for this reaction:

3 0

3 years ago

Read 2 more answers

What type of decay characterizes the change of radioactive nuclides to their respective daughter products?

tigry1 [53]

I believe the correct answer is the second option. The type of decay that characterizes the change of nuclides to their respective daughter products would be exponential decay. This type of decay is characterized by the decrease of quantity of a material according to the equation y=ab^x.

8 0

3 years ago

Map Formulate your hypothesis. List down the materials. • Write the methods.

Whitepunk [10]

Answer:

How to Formulate an Effective Research Hypothesis

State the problem that you are trying to solve. Make sure that the hypothesis clearly defines the topic and the focus of the experiment.

Try to write the hypothesis as an if-then statement. ...

Define the variables.

Explanation:

5 0

2 years ago

For the of freezing liquid ethanol at a given temperature and pressure,A. ΔH is positive and ΔS is positive.B. ΔH is positive an

Ksivusya [100]

Answer:

ΔH is negative and ΔS is negative.

Explanation:

Endothermic reaction -

The type of reaction in which energy is absorbed in the form of heat is known as endothermic reaction .

The reaction mixture usually get cooled after the reaction .( temperature decreases ) .

The sign of ΔH of an Endothermic reaction is positive .

For the of process of freezing the liquid ethanol , energy in the form of heat is released and hence , exothermic reaction ΔH is negative .

In the process of freezing , liquid is converted to solid , i.e. , the randomness reduces , and hence , entropy also decreases , hence , ΔS is negative .

3 0

3 years ago

Determine the percent yield of a reaction that produces 28.65 g of Fe when 50.00 g of Fe2O3 react with excess Al according to th

Luba_88 [7]

Answer:

The percent yield of the reaction is 82%

Explanation:

First step: make the chemist equation.

2 Al (s) + Fe2O3 (s) → 2 Fe (s) + Al2O3 (s)

As the statement says that aluminun is in excess, the limiting reactant is the Fe2O3

Second step: Find out the moles in the reactant.

Molar weight Fe2O3: 159.7 g/m

Mass / Molar weight = moles

50 g /159.7 g/m = 0.313 moles

Third step: Analyse the reaction. 1 mol of Fe2O3 makes 2 moles of Fe.

1 mol Fe2O3 ____ 2Fe

0.313 mol Fe2O3 ____ 0.626 moles

Molar weight Fe = 55.85 g/m

Moles . molar weight = mass

55.85g/m . 0.626m = 34.9 grams

This will be the 100% yield of the reaction but we only made 28.65 g

34.9 g ____ 100%

28.65 g ____ 82.09 %

3 0

3 years ago

Read 2 more answers