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3 years ago

Summary of the periodic table

1 answer:

4 0

The periodic table to chart which arranges all of the unknown elements to the automatic numbers the columns in the periodic table are called families or groups the rows are called periods

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Determine the theoretical yield of HCl if 60.0 g of BC13 and 37.5 g of H20 are reacted according to the following balanced react

Pie

Answer : The theoretical yield of HCl is, 56.1735 grams

Explanation : Given,

Mass of $BCl_3$ = 60 g

Mass of $H_2O$ = 37.5 g

Molar mass of $BCl_3$ = 117 g/mole

Molar mass of $H_2O$ = 18 g/mole

Molar mass of $HCl$ = 36.5 g/mole

First we have to calculate the moles of $BCl_3$ and $H_2O$ .

$\text{Moles of }BCl_3=\frac{\text{Mass of }BCl_3}{\text{Molar mass of }BCl_3}=\frac{60g}{117g/mole}=0.513moles$

$\text{Moles of }H_2O=\frac{\text{Mass of }H_2O}{\text{Molar mass of }H_2O}=\frac{37.5g}{18g/mole}=2.083moles$

Now we have to calculate the limiting and excess reagent.

The balanced chemical reaction is,

$BCl_3(g)+3H_2O(l)\rightarrow H_3BO_3(s)+3HCl(g)$

From the balanced reaction we conclude that

As, 1 mole of $BCl_3$ react with 3 mole of $H_2O$

So, 0.513 moles of $BCl_3$ react with $3\times 0.513=1.539$ moles of $H_2O$

From this we conclude that, $H_2O$ is an excess reagent because the given moles are greater than the required moles and $BCl_3$ is a limiting reagent and it limits the formation of product.

Now we have to calculate the moles of $HCl$ .

As, 1 mole of $BCl_3$ react to give 3 moles of $HCl$

So, 0.513 moles of $BCl_3$ react to give $3\times 0.513=1.539$ moles of $HCl$

Now we have to calculate the mass of $HCl$ .

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

$\text{Mass of }HCl=(1.539mole)\times (36.5g/mole)=56.1735g$

Therefore, the theoretical yield of HCl is, 56.1735 grams

7 0

3 years ago

15.0 g of cream at 10.0 ℃ are added to an insulated cup containing 150.0 g of coffee at 78.6 °C. Calculate the equilibrium tempe

elena-14-01-66 [18.8K]

Answer:

The equilibrium temperature of the coffee is 72.4 °C

Explanation:

Step 1: Data given

Mass of cream = 15.0 grams

Temperature of the cream = 10.0°C

Mass of the coffee = 150.0 grams

Temperature of the coffee = 78.6 °C

C = respective specific heat of the substances( same as water) = 4.184 J/g°C

Step 2: Calculate the equilibrium temperature

m(cream)*C*(T2-T1) = -m(coffee)*c*(T2-T1)

15.0 g* 4.184 J/g°C *(T2 - 10.0°C) = -150.0g *4.184 J/g°C*(T2-78.6°C)

62.76T2 - 627.6 = -627.6T2 + 49329.36

690.36T2 = 49956.96

T2 = 72.4 °C

The equilibrium temperature of the coffee is 72.4 °C

7 0

3 years ago

10 Points! Which type of fossil is formed when a rock hardens inside a mold fossil?

irina [24]

Answer:

I'm sure it's option A. Cast Fossil

3 0

3 years ago

Consider the nuclear equation below. 222/66Rn-->218/?Po+4/2He Which is the missing value that will balance the equation? 84 8

erastovalidia [21]

<h3>Answer:</h3>

<h3>Explanation:</h3>

The nuclear equation shows the decay of Radon-222 by emitting an alpha particle to form polonium-218.
When a radioactive isotope undergoes alpha-decay, the mass number is decreased by 4 while the atomic number decreases by 2.
Therefore, the complete nuclear equation is;

²²²₈₆Rn → ²¹⁸₈₄Po + ⁴₂He

The atomic number of Radon-222 decreases from 86 to 84 while the mass number decreases from 222 to 218, forming polonium-218.

4 0

3 years ago

Read 2 more answers

Why is sucrose insoluble in dichloromethane?

Vika [28.1K]

Sucrose is insoluble in dichloromethane because dichloromethane is not a polar solvent.
Sucrose is soluble in water because the molecules of sucrose has the ability to react with the molecules of water and thereby forming hydrogen bond which enhance the dispersion of sucrose in the water.
Sugar can not react in a similar way with dichloromethane because they do not possess chemical species that can react together to form bonds. Thus, sugar is a polar substance which can not dissolve in a non-polar solvent.

5 0

3 years ago