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2 years ago

2. A quantity of 1.922g of methanol (CH3OH) was burned in a constant-volume

1 answer:

5 0

Mass of methanol (CH3OH) = 1.922 g
Change in Temperature (t) = 4.20°C
Heat capacity of the bomb plus water = 10.4 KJ/oC
The heat absorbed by the bomb and water is equal to the product of the heat capacity and the temperature change.
Let’s assume that no heat is lost to the surroundings. First, let’s calculate the heat changes in the calorimeter. This is calculated using the formula shown below:
qcal = Ccalt
Where, qcal = heat of reaction
Ccal = heat capacity of calorimeter
t = change in temperature of the sample
Now, let’s calculate qcal:
qcal = (10.4 kJ/°C)(4.20°C)
= 43.68 kJ
Always qsys = qcal + qrxn = 0,
qrxn = -43.68 kJ
The heat change of the reaction is - 43.68 kJ which is the heat released by the combustion of 1.922 g of CH3OH. Therefore, the conversion factor is:

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Chemistry help! Zoom in to see better!!

inna [77]

Answer:

11.9 g of nitrogen monoxide

Explanation:

We'll begin by calculating the number of mole in 6.75 g of NH₃. This can be obtained as follow:

Mass of NH₃ = 6.75 g

Molar mass of NH₃ = 14 + (3×1)

= 14 + 3

= 17 g/mol

Mole of NH₃ =?

Mole = mass /molar mass

Mole of NH₃ = 6.75 / 17

Mole of NH₃ = 0.397 mole

Next, we shall determine the number of mole of NO produced by the reaction of 0.397 mole of NH₃. This can be obtained as follow:

4NH₃ + 5O₂ —> 4NO + 6H₂O

From the balanced equation above,

4 moles of NH₃ reacted to produce 4 moles of NO.

Therefore, 0.397 mole of NH₃ will also react to produce 0.397 mole of NO.

Finally, we shall determine the mass of 0.397 mole of NO. This can be obtained as follow:

Mole of NO = 0.397 mole

Molar mass of NO = 14 + 16 = 30 g/mol

Mass of NO =?

Mass = mole × molar mass

Mass of NO = 0.397 × 30

Mass of NO = 11.9 g

Thus, the mass of NO produced is 11.9 g

7 0

2 years ago

Which electron configuration represents the element carbon (atomic number 6)?

trapecia [35]

1s2 2s2 2p2 i hope this helps

5 0

2 years ago

The quantity, 1,385 mg is equivalent to in scientific notation

Agata [3.3K]

Answer:

The answer is 1385 x10∧ -3

Explanation:

Scientific notation is a quick way to represent a number using notation in exponential form or powers of base ten.

This notation allows us to express too large or small numbers easily.

For example:

500 is written as 5x10∧2; Where the power 2 represents the number of 0's that follow 5.

0.0093 is written as 9.3x10∧-3; Where the power -3 represents the number of times the comma was moved to the right.

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2 years ago

Differentiate between Acidic radical and basic radical

Paladinen [302]

Explanation:

Acidic radical

Acid radical is the ion formed after the removal of Hydrogen ion (H+) from an acid. Example: When H2SO4 loses H+ ion, it forms HSO4− which is an acid radical.

Basic radical

The ion formed after the removal of hydroxide ion (OH−) from a base is known as basic radical.

3 0

2 years ago

Select the correct answer. When an atom in a reactant loses electrons, what happens to its oxidation number? A. Its oxidation nu

vfiekz [6]

Answer:

C. Its oxidation number increases.

Explanation:

Oxidation is defined as the loss of electrons by an atom while reduction is the gain of electrons by an atom.
Atoms of elements have an oxidation number of Zero in their elemental state.
When an atom looses electrons it undergoes oxidation and its oxidation number increases.
For example, an atom of sodium (Na) at its elemental state has an oxidation number of 0. When the sodium atom looses an electrons it becomes a cation, Na+, with an oxidation number of +1 , the loss of electron shows an increase in oxidation number from 0 to +1.

8 0

2 years ago

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