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3 years ago

What mass of natural gas (CH4) must you burn to emit 264 kJ of heat?

1 answer:

7 0

The heat released by cpmolete the combustion of organic products with oxygen is called heat of combustion.

Here 1 mol of CH4 realesed 802.3 KJ

To emit 264 kJ you multiply you need (1 mol of CH4/802.3 kJ)* 264 kJ = 0.329 mol of CH4

The molar mass, MM, of CH4 is 12 g/mol + 4*1g/mol = 16 g/mol

The to obtain the mass multiply the number of moles times the molar mass:

mass = n * MM = 0.329mol * 16g/mol = 5.26 grams

Answer: 5.26 grams

You might be interested in

Which of the following is an example of an insoluble substance being added to water?

Leni [432]

Answer:

Explanation: “Insoluble” generally means that a substance does not dissolve in water. Some examples include: sand, fats, wood, metals, and plastic. When we put them in water and try to mix them, they will not dissolve.

Explanation:

5 0

3 years ago

Calculate the percent ionization of nitrous acid in a solution that is 0.249 M in nitrous acid. The acid dissociation constant o

sattari [20]

Answer:

4.26 %

Explanation:

There is some info missing. I think this is the original question.

Calculate the percent ionization of nitrous acid in a solution that is 0.249 M in nitrous acid. The acid dissociation constant of nitrous acid is 4.50 × 10 ⁻⁴.

Step 1: Given data

Initial concentration of the acid (Ca): 0.249 M

Acid dissociation constant (Ka): 4.50 × 10 ⁻⁴

Step 2: Write the ionization reaction for nitrous acid

HNO₂(aq) ⇒ H⁺(aq) + NO₂⁻(aq)

Step 3: Calculate the concentration of nitrite in the equilibrium ([A⁻])

We will use the following expression.

$[A^{-} ] = \sqrt{Ca \times Ka } = \sqrt{0.249 \times 4.50 \times 10^{-4} } = 0.0106 M$

Step 4: Calculate the percent ionization of nitrous acid

We will use the following expression.

$\alpha = \frac{[A^{-} ]}{[HA]} \times 100\% = \frac{0.0106M}{0.249} \times 100\% = 4.26\%$

4 0

3 years ago

The mass spectrum of an unknown compound has a molecular ion peak with a relative intensity of 57.10% and an M+1 peak of 6.83%.

max2010maxim [7]

There are 11 Carbon atoms in the compound.

Solution:

Carbon atom count is the ratio of the M peak to the M+1 peak.

$\text{ Number of Carbon atoms }=\frac{\text { Relative intensity of } M+1 \text { peak }}{0.011 \times \text { Relative tntensity of } M \text { peak }}$

Here M peak is 57.10% and M+1 peak is 6.83%. On applying the values in the formula we get,

$\frac{0.0683}{0.011\times0.571g} = 10.87\approx11$

Therefore, the number of Carbon atoms in the compound are 11.

Refer the image attached below for a better understanding of M peak and M+1 peak.

The heaviest ion that has the greatest m/z value is said to be the molecular ion peak in mass spectrum.

6 0

4 years ago

Who much the velocity of a body when it travels 600m in 5 min

Gwar [14]

Answer:

2 m/s

Explanation:

Applying the formulae of velocity,

V = d/t............. Equation 1

Where V = Velocity of the body, d = distance, t = time

From the question,

Given: d = 600 m, t = 5 minutes = (5×60) = 300 seconds.

Substitute these values into equation 1

V = 600/300

V = 2 m/s.

Hence the velocity of the body when it travels is 2 m/s

3 0

3 years ago

How many atoms of carbon are represented in 3CH3CH2O? 2 4 6 8

GenaCL600 [577]

Answer: 6

Explanation:

1) The structure shown is:

3CH₃CH₂O

2) The molecule is CH₃CH₂O. The chemical formula is CH₃CH₂O. The subscripts indicate the number of atoms of the corresponding atom in each molecule.

Then, there are 1 + 1 = 2 atoms of C, 3+ 2 = 5 atoms of H, and 1 atom of O.

3) The number in front of the molecule is the coefficient. It is 3, and it tells the number of molecules.

So, there are 3 molecules, which means that you have 3 times a many atoms as calculated previously.

That is 3×2 = 6 atoms of C, 3 × 5 = 15 atoms of H, and 3 × 1 = 3 atoms of O.

Then, the number of atoms of carbon (C) in 3 molecules is 6

4 0

3 years ago