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3 years ago

Is a burning log an exothermic or endothermic event if the log is the system?

Chemistry

2 answers:

Katyanochek1 [597]3 years ago

8 0

Answer:

Exothermic

Explanation:

Burning wood provides heat through the exothermic chemical reaction of oxygen (O) with cellulose (C6H10O5), the major chemical component of wood, to produce carbon dioxide (CO2), steam (H2O) and heat.

yaroslaw [1]3 years ago

3 0

Answer:

Im the one who dont know the answer

You might be interested in

B. Why is this number called a "mass” number?

deff fn [24]

<u>Answer:</u>

The mass of the atom depends on the sub atomic particles present in the nucleus of an atom.

That is, the protons and the neutrons.

Electrons are present around the nucleus and the mass is negligible since its mass is very very less.

<em>mass of a proton = $1.673\times10^{-27} kg$ </em>

<em>mass of a neutron = $1.675 \times 10^{-27} kg$ </em>

<em>mass of an electron = $9.109 \times 10^{-31} kg$ </em>

Mass number represents the mass of one particular isotope and it is a whole number for example, $_6 C^{13}$

Mass number is 13 and atomic number is 6 for the carbon isotope C-13.

Atomic mass is different from mass number and it is a fraction since it is the average atomic mass of all the isotopes of an atom.

Atomic mass of C is 12.011 amu which we see in the periodic table is the average atomic mass of isotopes C-12, C-13 and C-14.

7 0

3 years ago

10.Using the below valency chart, write chemical formula for aluminum oxide and

sweet [91]

The chemical formula of aluminum chloride is AlCl₃ and the chemical formula of aluminum oxide is Al₂O₃.

<h3>Aluminum chloride</h3>

The chemical formula of aluminum chloride is written as;

Al³⁺ + Cl⁻ → AlCl₃

<h3>Aluminum oxide</h3>

The chemical formula of aluminum oxide is written as;

Al³⁺ + O²⁻ → Al₂O₃

Thus, the chemical formula of aluminum chloride is AlCl₃ and the chemical formula of aluminum oxide is Al₂O₃.

Learn more about chemical formula here: brainly.com/question/26388921

#SPJ1

5 0

1 year ago

Gasoline and kerosene (specific gravity 0.820) are blended to obtain a mixture with a specific gravity of 0.770. Calculate the v

Dmitrij [34]

Answer:

The volumetric ratio is 0,71

Explanation:

Let's begin with the equation:

$Db = Mb/Vb$ (1)

Where:

Db: Blend Density, Mb: Blend Mass and Vb: Blend Volume

And we know: $Vb = Vg + Vk$ (2)

Where:

Vg: Gasoline Volume and Vk: Kerosene Volume

Therefore replacing (2) into (1):

$Db = (Mg + Mk) / (Vg + Vk)$

$Db = (Dg * Vg + Dk * Vk)/(Vg + Vk)$ (3)

Where:

Dg: Gasoline Density and Dk: Kerosene Density

The specific gravity is defined as:

$SG = Substance Density / Reference Density$

Therefore:

$Db = SGb * Dref\\Dg = SGg * Dref\\Dk = SGk * Dref$

Where:

Dref: Reference Density

SGb: Blend Specific Gravity

SGg: Gasoline Specific Gravity (which is 0.7 approximately)

SGk: Kerosene Specific Gravity

Replacing these equations into (3) we get:

$SGb * Dref = (SGg * Dref * Vg + SGk * Dref * Vk)/(Vg + Vk)$

$SGb * Dref = Dref * (SGg * Vg + SGk * Vk)/(Vg + Vk)$

$SGb = (SGg * Vg + SGk * Vk)/(Vg + Vk)$

$SGb * (Vg + Vk) = SGg * Vg + SGk * Vk$

$SGb * Vg + SGb* Vk = SGg * Vg + SGk * Vk$

Replacing with the Specific Gravity data, we obtain:

$0.77 * Vg + 0.77 * Vk = 0.7 * Vg + 0.82 * Vk$

$0.77 * Vg - 0.7 * Vg = 0.82 * Vk - 0.77 * Vk$

$0.07 * Vg = 0.05 * Vk$

$Vg/Vk = 0.05/0.07$

$Vg/Vk = 0.71$

8 0

2 years ago

If 1.02 g of nickel reacted with 750. mL of 0.112 M hydrobromic acid, how much of each will be present at the end of the reactio

kati45 [8]

Answer:

35.1% is percent yield

Explanation:

<em>Full question: Assume no volume change. If you formed 0.0910 atm of gas, what is the percent yield?</em>

<em />

The reaction that is occurring is:

Ni + 3HBr → NiBr₃ + 3/2H₂(g)

First, we will determine moles of Ni and HBr to determine limiting reactant and theoretical yield

Using ideal gas law, we can determine the moles of hydrogen formed. Thus, we can find percent yield:

<em>Moles Ni (Molar mass: 58.69g/mol):</em>

1.02g * (1mol / 58.69g) = 0.01738moles Ni

<em>Moles HBr:</em>

0.750L * (0.112mol/L) = 0.084 moles of HBr.

For a complete reaction of the 0.084 moles of HBr you need:

0.084mol HBr * (1 mole Ni / 3 moles HBr) = 0.028 moles of Ni.

As there are just 0.01738 moles of Ni, the Ni is limiting reactant. Assuming a theoretical yield, moles of H₂ produced are:

0.01738moles Ni * (3/2 H₂ / 1 mol Ni) = 0.02607 moles H₂

Now, moles of H₂ produced are:

PV = nRT

PV/RT = n

<em>Where P is pressure (0.0910atm)</em>

<em>V is volume (2.50L)</em>

<em>R is gas constant (0.082atmL/molK)</em>

<em>T is absolute temperature in Kelvin (30°C + 273.15 = 303.15K)</em>

<em>And n are moles</em>

PV/RT = n

0.0910atm*2.50L/0.082atmL/molK*303.15K = n

0.00915 moles = n

<em />

And percent yield (Produced moles / Theoretical moles * 100) is:

0.00915 moles / 0.02607moles =

<h3>35.1% is percent yield</h3>

8 0

2 years ago

Would it be C..? <br> More NO2 and SO2 would form..help..please and thank you

Scorpion4ik [409]

Answer:

C. More NO2 and SO2 will form

Explanation:

Le Chatelier's Principle : It predicts the behavior of equilibrium due to change in pressure , temperature , volume , concentration etc

It states that When external changes are introduced in the equilibrium then it will shift the equilibrium in a direction to reduce the change.

In given Reaction SO3 is introduced(increased) .

So equilibrium will shift in the direction where SO3 should be consumed(decreased)

Hence the equilibrium will go in backward direction , i.e

$NO + SO_{3} \rightarrow NO_{2} + SO_{2}$

So more and more Of NO2 and SO2 will form

7 0

3 years ago