What’s the answer to this question pls help

I know how to solve it with D=M/V and M1V1 however the answer isn’t correct. Help me please

lara31 [8.8K]

Answer:

23.28 g of O2.

Explanation:

We'll begin by calculating the mass of hexane. This can obtain as follow:

Volume of hexane = 10 mL

Density of hexane = 0.66 g/mL

Mass of hexane =?

Density = mass /volume

0.66 = mass of hexane /10

Cross multiply

Mass of hexane = 0.66 x 10

Mass of hexane = 6.6 g

Next, we shall write the balanced equation for the reaction. This is given below:

2C6H14 + 19O2 —> 12CO2 + 14H2O

Next, we shall determine the masses of C6H14 and O2 that reacted from the balanced equation. This can be obtained as follow:

Molar mass of C6H14 = (12.01x6) + (1.008 x 14)

= 72.06 + 14.112

= 86.172 g/mol

Mass of C6H14 from the balanced equation = 2 x 86.172 = 172.344 g

Molar mass of O2 = 16x2 = 32 g/mol

Mass of O2 from the balanced equation = 19 x 32 = 608 g

From the balanced equation above,

172.344 g of C6H14 reacted with 608 g of O2.

Finally, we shall determine the mass of O2 needed to react with 10 mL (i.e 6.6 g) of hexane, C6H14. This can be obtained as follow:

From the balanced equation above,

172.344 g of C6H14 reacted with 608 g of O2.

Therefore, 6.6 g of C6H14 will react with = (6.6 x 608)/172.344 = 23.28 g of O2.

Therefore, 23.28 g of O2 is needed for the reaction.

8 0

3 years ago

What are the molarity and the normality of a solution made

Nikitich [7]

Explanation:

It is known that molarity is the number of moles present in a liter of solution.

Mathematically, Molarity = $\frac{\text{no. of moles}}{\text{volume in liter}}$

Hence, calculate the molarity of given solution as follows.

Molarity of citric acid = $\frac{\text{mass of citric acid}}{\text{molar mass of citric acid}} \times \frac{1}{\text{volume of solution(L)}}$

= $\frac{25 g}{192.13 g/mol} \times \frac{1}{0.75 L}$

= 0.173 M

As citric acid is a triprotic acid so, upon dissociation it gives three hydrogen ions.

Normality = Molarity × no. of hydrogen or hydroxide ions

= 0.173 × 3

= 0.519 N

Thus, we can conclude that molarity of given solution is 0.173 and its normality is 0.519 N.

3 0

3 years ago

Ni-cad (nickel–cadmium) batteries have a slightly lower cell potential than the common alkaline value of 1.5 v normally used in

Lorico [155]

The half-reaction are:

Cd ---> Cd(OH)₂
The oxidation number of Cd changed from 0 to +2. So, the number of mol electron transferred here is 2.

NiO(OH) --> Ni(OH)₂
The oxidation number of Cd changed from +3 to +2. So, the number of mol electron transferred here is 1.

Now, the greatest common factor would be 2. So, we use n=2 for the formula for ΔG°. F is Faraday's constant equal to 96,485 J/mol e.

ΔG° = nFE° = (2)(96,485)(1.5) =<em> 289,455 J</em>

6 0

3 years ago

Using the periodic table to locate each element, write the electron configuration of(c) Re.

Aleksandr [31]

Rhenium is a chemical element with the symbol Re and atomic number 75. The electron configuration of Re is [Xe] $6s^{2} 4f^{14} 5d^{5}$ .

<h3>How to write an electronic configuration?</h3>

1. Identify the given element and its atomic number from the periodic table.

2. Write the electron configuration by the energy level and the type of orbital first, then the number of electrons present in the orbital as superscript.

The easiest way to write the electronic configuration for any element is by using a diagonal rule for electron filling order in the different subshells according to the Aufbau principle.

The 3 rules for writing the electron configuration in the orbital box diagram are – the Aufbau rule, the Pauli-exclusion rule, and Hund's Rule.

To learn more about electronic configuration, refer

https://brainly.ph/question/73419

#SPJ4

5 0

2 years ago

What happens to the energy that is lost when water freezes?

SVEN [57.7K]

<span>As we know through the principle of conservation of energy, energy can neither be created nor destroyed. Therefore, the energy removed from the water in order to make it freeze is absorbed by the surroundings. This is why the surroundings in which freezing is taking place are below freezing. This is more easily illustrated in the example of condensation. If you were to hold a plate over a pot of boiling water, some of the water would give its energy to the plate and condense on its surface.</span>

4 0

3 years ago

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