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Mademuasel [1]
3 years ago
5

Evidence of chemical reactions include changes in

Chemistry
1 answer:
trasher [3.6K]3 years ago
7 0

Answer:

color, state, odor

Explanation:

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A 2. 75-l container filled with co2 gas at 25°c and 225 kpa pressure springs a leak. When the container is re-sealed, the pressu
Serjik [45]

The number of moles of gas lost is  0.0213 mol. It can be solved with the help of Ideal gas law.

<h3>What is Ideal law ?</h3>

According to this law, "the volume of a given amount of gas is directly proportional to the number on moles of gas, directly proportional to the temperature and inversely proportional to the pressure. i.e.

PV = nRT.

Where,

  • p = pressure
  • V = volume (1.75 L = 1.75 x 10⁻³ m³)
  • T =  absolute temperature
  • n = number of moles
  • R =  gas constant, 8.314 J*(mol-K)

Therefore, the number of moles is

n = PV / RT

State 1 :

  • T₁ = (25⁰ C = 25+273 = 298 K)
  • p₁ = 225 kPa = 225 x 10³ N/m²

State 2 :

  • T₂ = 10 C = 283 K
  • p₂ = 185 kPa = 185 x 10³ N/m²

The loss in moles of gas from state 1 to state 2 is

Δn = V/R (P₁/T₁ - P₂/T₂ )

V/R = (1.75 x 10⁻³ m³)/(8.314 (N-m)/(mol-K) = 2.1049 x 10⁻⁴ (mol-m²-K)/N

p₁/T₁ = (225 x 10³)/298 = 755.0336 N/(m²-K)

p₂/T₂ = (185 x 10³)/283 = 653.7102 N/(m²-K)

Therefore,

Δn = (2.1049 x 10⁻⁴ (mol-m²-K)/N)*(755.0336 - 653.7102 N/(m²-K))

    = 0.0213 mol

Hence, The number of moles of gas lost is 0.0213 mol.

Learn more about ideal gas here ;

https://brainly.in/question/641453

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3 0
2 years ago
Consider the following data for five hypothetical elements: Q, W, X, Y, and Z. Rank the elements from most reactive to least rea
Natalka [10]

Answer:

Y, Q, W, Z and X

Y > Q > W > Z > X

Explanation:

To know the most reactive element, the element will be able to displace other metal in it compound. We also have to observe if the reaction occur. If the reaction didn't occur, that means the element is not reactive than the metal found in the other reactant. Invariably their will be no displacement.

Q + w+ Reaction occurs

Q element displace the metal w in it compound . This means Q is more reactive.

x +z+ No reaction

No reaction here. This means x is less reactive than z as it couldn't displace z in it compound.

w + z+ Reaction occurs

w is more reactive than z as it displaces z in it compound.

Q+ + Y Reaction occurs

Y is more reactive than Q as it displaces Q in it compounds.

Therefore, the most reactive to the least reactive is arrange as follows.

Y, Q, W, Z and X

8 0
3 years ago
how many moles of sodium hydroxide (NaOH) are required to completely neutralize 2 mol of nitric acid (HNO3)
Brut [27]

2 moles of sodium hydroxide will be needed.

<h3><u>Explanation</u>:</h3>

Sodium hydroxide is a compound which is a base and nitric acid is the acid. The formula of the nitric acid is HNO3 and that of sodium hydroxide is NaOH.

The reaction between them are

NaOH +HNO3 =NaNO3 +H2O.

So here we can see that 1 mole of sodium hydroxide reacts with 1 mole of nitric acid to produce 1 mole of sodium nitrate and 1 mole of water.

So for 2 moles of nitric acid, 2 moles of sodium hydroxide will be required.

6 0
3 years ago
Which of these describes an ethical dilemma that drug designers could face?
LenKa [72]

The statement 'whether people should take medicine or if they should seek alternative treatments' describes an ethical dilemma that drug designers face.

<h3>What is drug development?</h3>

Drug development refers to all the processes from target drug identification to drug validation and commercialization.

Drug development involves different stages of development including preclinical and clinical trials.

Ethical dilemmas in drug development include the release of a drug that is ineffective when compared to parallel treatments.

Learn more about drug development here:

brainly.com/question/8187660

4 0
2 years ago
Why is the cell membrane essential for cell homeostasis?
Nadya [2.5K]
Hello,

Here is your answer:

The proper answer to this question is option C "To allow waste to exit the cell"! The cell membrane controls the matieral that goes in and out of the cell!

Your answer is C.

If you need anymore help feel free to ask me!

Hope this helps!
3 0
3 years ago
Read 2 more answers
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