Can someone answer this please?

yawa3891 [41]

The % yield of Ca(OH)₂ : 62.98%

<h3>Further eplanation </h3>

Percent yield is the compare of the amount of product obtained from a reaction with the amount you calculated

General formula:

Percent yield = (Actual yield / theoretical yield )x 100%

An actual yield is the amount of product actually produced by the reaction. A theoretical yield is the amount of product that you calculate from the reaction equation according to the product and reactant coefficients

Reaction

CaO + H₂O ⇒ Ca(OH)₂

mass CaO= 4.2 g

mol CaO(MW=56,0774 g/mol) :

$\tt mol=\dfrac{mass}{MW}\\\\mol=\dfrac{4.2}{56,0774 g/mol}\\\\mol=0.075$

mol Ca(OH)₂ based on mol CaO

mol ratio CaO : Ca(OH)₂,= 1 : 1, so mol Ca(OH)₂ = 0.075

mass Ca(OH)₂(MW=74,093 g/mol) ⇒ theoretical

$\tt mass=mol\times MW\\\\mass=0.075\times 74,093 g/mol\\\\mass=5.557~g$

% yield :

$\tt =\dfrac{actual}{theoretical}\times 100\%\\\\=\dfrac{3.5}{5.557}\times 100\%\\\\=62.98\%$

8 0

2 years ago

Every day, about 1 4 0 , 0 0 0 , 0 0 0 140,000,000140, comma, 000, comma, 000 plastic water bottles are bought in the United Sta

jeka94

Answer:

0.875 time.

Explanation:

The length of plastic water bottles are bought in the United States every day = (the no. of plastic water bottles are bought every day)(length of each bottle) = (140.0 million bottle)(0.25 m) = 35.0 million meter.

The length of the equator of the earth = 40.0 million meter.

∴ The times can the Earth's equator be circled by a line of plastic bottles used in the United States every day = (The length of plastic water bottles are bought in the United States every day)/(The length of the equator of the earth) = (35.0 million meter)/(40.0 million meter) = 0.875 times.

8 0

3 years ago

What is the solubility of MgCO₃ in a solution that contains 0.080 M Mg²⁺ ions? (Ksp of MgCO₃ is 3.5 × 10⁻⁸)

Alchen [17]

Answer: 4.4 x 10^-7

Explanation:

The dissociation equation for this reaction is:

MgCO3 (s) → Mg+2 (aq) + CO3-2 (aq)

$\text { So, } k_{s p}=(x+0.08) x$ (Here 0.08 >>> x )

$\begin{aligned}\Rightarrow 3.5 \times 10^{-8} &=0.08 \times x \\\Rightarrow x &=\frac{3.5}{0.08} \times 10^{-8} \\&=4.37 \times 10^{-7} \\\Rightarrow x & \approx 4.4 \times 10^{-7} \mathrm{~M}\end{aligned}$

So the solubility MgCO₃ in a solution that containing 0.080 M Mg²⁺ is 4.4 x 10^-7

7 0

2 years ago

What does the word "kinetic" indicate about

Natasha2012 [34]

It’s B. The kinetic molecular theory states that matter is made up of constantly moving particles.

4 0

1 year ago

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