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2 years ago

The first time scientists actually saw an atom was

Chemistry

1 answer:

-BARSIC- [3]2 years ago

6 0

<span>John Dalton was the first person to see an adam after Democritus theorized i</span>

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Air, with an initial absolute humidity of 0.016 kg water per kg dry air, is to be dehumidified for a drying process by an air co

amid [387]

Answer:

(a) The proportion of dry air bypassing the unit is 14.3%.

(b) The mass of water removed is 1.2 kg per 100 kg of dry air.

Explanation:

We can express the proportion of air that goes trough the air conditioning unit as $p_{d}$ and the proportion of air that is by-passed as $p_{bp}$ , being $p_{d}+p_{bp}=1$ .

The amount of water that goes into the drier inlet has to be 0.004 kg/kg, and can be expressed as:

$0.004 = 0.016*p_{bp}+ 0.002*p_{d}$

Replacing the first equation in the second one we have

$0.004 = 0.016*(1-p_{d})+ 0.002*p_{d}=0.016-0.016*p_{d}+0.002*p_{d}\\0.004 - 0.016 = (-0.016+0.002)*p_{d}\\-0.012 = -0.014*p_{d}\\p_{d}=\frac{-0.012}{-0.014}=0.857\\\\p_{bp}=1-p_{d}=1-0.857=0.143$

(b) Of every kg of dry air feed, 85.7% goes in to the air conditioning unit.

It takes (0.016-0.002)=0.014 kg water per kg dry air feeded.

The water removed of every 100 kg of dry air is

$100 kgDA*0.857*0.014 kgW/kgDA= 1.1998 \approx 1.2 kgW$

It can also be calculated as the difference in humiditiy between the inlet and the outlet: (0.016-0.004=0.012 kgW/kDA) and multypling by the total amount of feed (100 kgDA).

100 * 0.012 = 1.2 kgW

7 0

3 years ago

The chemical equation below shows the formation of aluminum oxide (Al2O3) from aluminum (Al) and oxygen (O2). 4Al 3O2 Right arro

Andrew [12]

Formation reaction is the formation of 1 mole of product from the constituents of the reactant molecules. The mass of oxygen that must react is 182 gm.

<h3>What is mass and molar mass?</h3>

Mass of the substance is the weight while the molar mass of the substance is the addition of the atomic mass of the individual mass of the constituent atoms of the compound or the molecule.

The chemical reaction can be shown as:

$\rm 4 Al + 3 O_{2} \rightarrow 2 Al_{2}O_{3}$

From the reaction, it can be said that 3 moles of oxygen are required to produce 2 moles of aluminium oxide, so x moles of oxygen will be required to produce 3.80 moles of aluminium oxide.

Solving for x:

$\begin{aligned}\rm 2x &= 3.80\times 3\\\\\rm x &= \dfrac{11.4}{2}\\\\&= 5.7\;\rm mol\end{aligned}$

If 1 mol of oxygen is 32 gm then 5.7 moles of oxygen will be 182.4 gm.

Therefore, option D. 182 gm is the mass of oxygen required.

Learn more about moles and molar mass here:

brainly.com/question/893495

3 0

2 years ago

You are taking a 578.23 mile trip to visit your grandparents. What is the distance of this trip in kilometers?

Tamiku [17]

578.23 miles = 930.6 kilometers (Rounded up to the nearest tenth.)

5 0

3 years ago

What mass of oxygen would form from 2.30 moles of water?

Serggg [28]

Answer : The mass of oxygen will be, 36.8 grams

Solution : Given,

Moles of water = 2.30 moles

Molar mass of $O_2$ = 32 g/mole

First we have to calculate the moles of oxygen.

The balanced chemical reaction will be,

$2H_2O\rightarrow 2H_2+O_2$

From the balanced reaction we conclude that

2 moles of water decomposes to give 1 mole of $O_2$

2.30 moles of water decomposes to give $\frac{2.3}{2}=1.15$ moles of $O_2$

Now we have to calculate the mass of oxygen.

$\text{Mass of }O_2=\text{Moles of }O_2\times \text{Molar mass of }O_2$

$\text{Mass of }O_2=(1.15moles)\times (32g/mole)=36.8g$

Therefore, the mass of oxygen will be, 36.8 grams

8 0

2 years ago

WILL MARK BRAINLIEST

levacccp [35]

Okay so i think to calculate volume change you use the ideal gas law . this is pressure x volume = amount of substance x ideal gas constant x temperature. i honestly don’t know where to go from there but i hope this helped a bit :(

8 0

2 years ago