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3 years ago

Perfume evaporating is it a chemical change or physical change

2 answers:

7 0

This is a physical change: a change of state: from liquid to gas.

This is not a chemical change, as no chemical reaction takes place: the substance is the same, but it changes the state at which it is in: there is no reaction with other chemical substances.

uysha [10]3 years ago

7 0

Physical Change. It's a liquid to a gas

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Which product is not made from a renewable resource? select one:

Lady bird [3.3K]

The answer is B plastic bags made from petroleum.

8 0

2 years ago

Read 2 more answers

For test 6 (150 hevy 50 light particles), what is the pressure contribution from the heavy particles?

lawyer [7]

Answer:

The pressure contribution from the heavy particles is 17.5 atm

Explanation:

According to Dalton's law of partial pressures, if there is a mixture of gases which do not react chemically together, then the total pressure exerted by the mixture is the sum of the partial pressures of the individual gases that make up the mixture.

In the simulation:

the pressure of the 50 light particles alone was determined to be 5.9 atm, the pressure of the 150 heavy particles alone was measured to be 17.5 atm,

the total pressure of the mixture of 150 heavy and 50 light particles was measured to be 23.4 atm

Total pressure = partial pressure of Heavy particles + partial pressure of light particles

23.4 atm = partial pressure of Heavy particles + 5.9 atm

Partial pressure of Heavy particles = (23.4 - 5.9) atm

Partial pressure of Heavy particles = 17.5 atm

Therefore, the pressure contribution from the heavy particles is 17.5 atm

4 0

2 years ago

Find percent yield:

saveliy_v [14]

Answer: The percent yield of the reaction is 91.8 %

Explanation:

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

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

For $B_5H_9$ :

Given mass of $B_5H_9$ = 4.0 g

Molar mass of $B_5H_9$ = 63.12 g/mol

Putting values in equation 1, we get:

$\text{Moles of }B_5H_9=\frac{4g}{63.12g/mol}=0.0634mol$

For oxygen gas:

Given mass of oxygen gas = 10.0 g

Molar mass of oxygen gas = 32 g/mol

Putting values in equation 1, we get:

$\text{Moles of oxygen gas}=\frac{10g}{32g/mol}=0.3125mol$

The chemical equation for the reaction of $B_5H_9$ and oxygen gas follows:

$2B_5H_9+12O_2\rightarrow 5B_2O_3+9H_2O$

By Stoichiometry of the reaction:

12 moles of oxygen gas reacts with 2 moles of $B_2H_5$

So, 0.3125 moles of oxygen gas will react with = $\frac{2}{12}\times 0.3125=0.052mol$ of $B_2H_5$

As, given amount of $B_2H_5$ is more than the required amount. So, it is considered as an excess reagent.

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

By Stoichiometry of the reaction:

12 moles of oxygen gas produces 5 moles of $B_2O_3$

So, 0.3125 moles of oxygen gas will produce = $\frac{5}{12}\times 0.3125=0.130moles$ of water

Now, calculating the mass of $B_2O_3$ from equation 1, we get:

Molar mass of $B_2O_3$ = 69.93 g/mol

Moles of $B_2O_3$ = 0.130 moles

Putting values in equation 1, we get:

$0.130mol=\frac{\text{Mass of }B_2O_3}{69.63g/mol}\\\\\text{Mass of }B_2O_3=(0.130mol\times 69.63g/mol)=9.052g$

To calculate the percentage yield of $B_2O_3$ , we use the equation:

$\%\text{ yield}=\frac{\text{Experimental yield}}{\text{Theoretical yield}}\times 100$

Experimental yield of $B_2O_3$ = 8.32 g

Theoretical yield of $B_2O_3$ = 9.052 g

Putting values in above equation, we get:

$\%\text{ yield of }B_2O_3=\frac{8.32g}{9.052g}\times 100\\\\\% \text{yield of }B_2O_3=91.8\%$

Hence, the percent yield of the reaction is 91.8 %

6 0

3 years ago

Plz help me out!!!!!

Lelu [443]

Answer:

i am not 100% sure but im pretty sure there is.

Explanation:

7 0

2 years ago

Which of the following is an expression of Charles's law?

HACTEHA [7]

Answer:

Explanation:

V/T

4 0

3 years ago