All categories

1 year ago

Mass of 0.432 moles of C8H9O4?

2 answers:

7 0

Find one mole
8 C = 8 * 12 = 96
9 H = 1 * 9 = 9
4 O = 4 *16 = 64
Total = 169

1 mol = 169 grams.
0.432 mol = x

1/0.432 = 169/x
x = 0.432 * 169
x = 73.0 grams

romanna [79]1 year ago

4 0

Explanation:

It is known that number of moles present in a substance is equal to the mass divided by molar mass.

Mathematically, No. of moles = $\frac{mass}{\text{molar mass}}$

As it is given that number of moles are 0.432 moles and molar mass of $C_{8}H_{9}O_{4}$ is 169.15 g/mol.

Hence, calculate the mass of $C_{8}H_{9}O_{4}$ is as follows.

No. of moles = $\frac{mass}{\text{molar mass}}$

0.432 mol = $\frac{mass}{169.15 g/mol}$

mass = 73.072 g

Thus, we can conclude that the mass of 0.432 moles of $C_{8}H_{9}O_{4}$ is 73.072 g.

You might be interested in

Consider the following system at equilibrium where H° = -87.9 kJ, and Kc = 83.3, at 500 K. PCl3(g) + Cl2(g) PCl5(g) If the VOLUM

7nadin3 [17]

Answer:

The value of Kc C. remains the same.

The value of Qc C. is less than Kc.

The reaction must: A. run in the forward direction to reestablish equilibrium

The number of moles of Cl2 will B. decrease.

Explanation:

Le Chatelier's Principle states that if a system in equilibrium undergoes a change in conditions, it will move to a new position in order to counteract the effect that disturbed it and recover the state of equilibrium.

A decrease in volume causes the system to evolve in the direction in which there is less volume, that is, where the number of gaseous moles is less.

But temperature is the only variable that, in addition to influencing equilibrium, modifies the value of the constant Kc. So if the volume of the equilibrium system is suddenly decreased at constant temperature: The value of Kc remains the same.

As mentioned, if the volume of an equilibrium gas system decreases, the system moves to where there are fewer moles. In this case, being:

PCl₃(g) + Cl₂(g) ⇔ PCl₅(g)

The equilibrium in this case then shifts to the right because there is 1 mole in the term on the right, compared to the two moles on the left. So, The reaction must: A. run in the forward direction to reestablish equilibrium.

By decreasing the volume, and so that Kc remains constant, being:

$Kc=\frac{[PCl_{5} ]}{[PCl_{3}]*[Cl_{2} ]}=\frac{\frac{nPCl_{5} }{Volume} }{\frac{nPCl_{3}}{Volume}*\frac{nCl_{2} }{Volume} } =\frac{nPCl_{5}}{nPCl_{3}*nCl_{2}} *Volume$

where nPCl₅, nPCl₃ and nCl₂ are the moles in equilibrium of PCl₅, PCl₃ and Cl₂

so, the number of moles of Cl₂ should decrease.The number of moles of Cl2 will B. decrease.

If the reaction quotient is less than the equilibrium constant, Qc <Kc, the system will evolve to the right, the direct reaction prevailing, to increase the concentration of products. So in this case, if the reaction moves to the right, the value of Qc C. is less than Kc.

3 0

1 year ago

Two students made the Lewis dot diagrams of NH3. The diagrams are as shown.

BigorU [14]

Answer : The correct option is, Only Student B

Explanation :

Lewis-dot structure : It shows the bonding between the atoms of a molecule and it also shows the unpaired electrons present in the molecule.

In the Lewis-dot structure the valance electrons are shown by 'dot'.

The given molecule is, $NH_3$

As we know that nitrogen has '5' valence electrons and hydrogen has '1' valence electron.

Therefore, the total number of valence electrons in $NH_3$ = 5 + 3(1) = 8

According to Lewis-dot structure, there are 6 number of bonding electrons and 2 number of non-bonding electrons.

The Lewis dot structure of student A is wrong because there is a coordinate bond present between the nitrogen and hydrogen is not covalent.

Thus, the correct Lewis-dot structure of $NH_3$ is shown by the student B.

4 0

1 year ago

On top of one of the peaks in rocky mountain national park the pressure of the atmosphere is 550 torr determine the boiling poin

Dahasolnce [82]

Answer:

The boiling point of water at 550 torr will be 91 °C or 364 Kelvin

Explanation:

Step 1: Data given

Pressure = 550 torr

The heat of vaporization of water is 40.7 kJ/mol.

Step 2: Calculate boiling point

⇒ We'll use the Clausius-Clapeyron equation

ln(P2/P1) = (ΔHvap/R)*(1/T1-1/T2)

ln(P2/P1) = (40.7*10^3 / 8.314)*(1/T1 - 1/T2)

⇒ with P1 = 760 torr = 1 atm

⇒ with P2 = 550 torr

⇒ with T1 = the boiling point of water at 760 torr = 373.15 Kelvin

⇒ with T2 = the boiling point of water at 550 torr = TO BE DETERMINED

ln(550/760) = 4895.4*(1/373.15 - 1/T2)

-0.3234 = 13.119 - 4895.4/T2

-13.4424= -4895.4/T2

T2 = 364.2 Kelvin = 91 °C

The boiling point of water at 550 torr will be 91 °C or 364 Kelvin

4 0

1 year ago

A pure gold bar is made of 19.55 mol of gold. What is the mass of the bar in grams

Law Incorporation [45]

(19.55 mol Au) / ( 1 ) x (196.97 g Au) / ( 1 mol Au) =
19.55 x 196.97 =
3850.76 g Au

I hope this helps you and have a great day!! :)

4 0

1 year ago

Read 2 more answers

Temperatures in Earth's interior increase with increasing depth. Seismic waves help to provide information on temperatures in Ea

Valentin [98]

Answer:

Temperature affects Seismic Wave speed.

Explanation:

Both temperature and pressure affect the speed of Seismic waves. The Speed of Seismic waves increases uniformly as pressure increases, meaning that as depth increases, pressure also increases which causes Seismic Wave speeds to increase as well. This can be calculated and the data can be gathered. Temperature on the other hand decreases the speed of Seismic Waves, therefore we can calculate the difference of speed between what the Seismic Wave should be at a certain pressure with the actual speed gathered. This difference in speed will allow us to determine the actual temperature at that level.

3 0

2 years ago