Scientific investigations must be well __________ to be sure the data collected will help answer the scientist's question

Hydrogen peroxide decomposes spontaneously to yield water and oxygen gas according to the reaction equation 2 H 2 O 2 ( aq ) ⟶ 2

Ede4ka [16]

Answer:

The value of temperature for unanalysed reaction is 456.1 K

Explanation:

Step 1: Data given

The activation energy of uncatalyzed reaction is 75.0 kJ/mol.

The activation energy of catalyzed reaction is 49.0 kJ/mol.

The temperature for catalyzed reaction is 25 °C

<u>Step 2:</u> The balanced equation

2 H2O2(aq) ⟶ 2H2O(l) + O2(g)

<u>Step 3:</u> According to Arrhenius equation:

k = Ae ^ (-Ea/RT)

⇒ with k = the rate constant

⇒ with Ea = the activation energy = 49 kJ/mol

⇒ with R = the universal gas constant = 8.314 J/mol*K

⇒ with T = the temperature = 298 K

For uncatalyzed reaction, the rate constant is calculated as:

k(uncatalyzed) = Ae ^ (-75000/8.314 J/mol*K * T)

k(uncatalyzed) = Ae ^ (-9020.93/T)

For catalyzed reaction, the rate constant is calculated as:

k(catalyzed) = Ae ^ (-Ea(catalyzed)/RT))

⇒ with Ea(catalyzed) = 49000 J/mol

⇒ with T = 298 K

k(catalyzed) = Ae ^ (-49000J/(8.314J/mol *K * 298K))

k(catalyzed) = Ae ^(-19.78)

k(catalyzed) = k(uncatalyzed)

Ae^(-19.78) = = Ae ^ (-9020.93/T)

-19.78 = -9020.93/T

T = -9020.93/-19.78

T = 456.1 K

The value of temperature for unanalysed reaction is 456.1 K

8 0

3 years ago

Read 2 more answers

What's the deffinition of igneous rock

Aliun [14]

<span>Igneous rocks are those rocks that were formed through cooling and solidifying the molten materials. The best example for igneous rock is solid volcanic java. Lava are liquid that comes from a volcano, but once it is dried and solidify, it becomes a rock and called igneous rock.
Another example is the granite and basalt. And according to research igneous rock comes from the latin word ignis which means fire. Thus this says it all. From a liquid becomes a rock.

</span>

7 0

4 years ago

Read 2 more answers

Temperature is the measurement of how hot or cold something is. Agree Disagree

Nataliya [291]

Answer:

Agree

Explanation:

7 0

3 years ago

Read 2 more answers

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

Magnesium chloride, MgCl2, is an important industrial chemical.

gavmur [86]

This problem is providing information about a reaction between magnesium and hydrochloric acid. However, the moles of the latter are required given 50 cm³ of a 0.2-M solution, making this problem more about the application of molarity. At the end, the answer turns out to be 0.01 mol.

<h3>Molarity:</h3>

In chemistry, we use units of concentration in order to represent the relative amounts of solute and solvent in a solution. More specifically, molarity relates the moles of the solute with the liters of solution according to:

$M=\frac{n}{V}$

Thus, since this problem asks for the moles of hydrochloric acid in 50 cm³ of a 0.2-M solution, we must first calculate the volume in liters with:

$V=50cm^3*\frac{1L}{1000cm^3} =0.050L$

To finally solve for n, moles, to obtain:

$0.2mol/L=\frac{n}{0.05L} \\\\n=0.2mol/L*0.05L\\\\n=0.01mol$

Learn more about molarity: brainly.com/question/9468209

8 0

3 years ago