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4 years ago

Consider the following equation for the combustion of acetone (C3H6O), the main ingredient in nail polish remover.

Chemistry

1 answer:

disa [49]4 years ago

4 0

Answer:

a) 4869 kJ will be released

b) 43.86 g of octane

Explanation:

The heat of combustion is the amount of heat released when 1 mol of a substance reacts with enough oxygen .

Since the heat of combustion is per mol of combustible substance what we are required to do in this problem is calculate number moles in the reactions although in a different manner.

a) MW C3H6O = 158 g/mol

mol C3H6O = 158 g x 1 mol/58.08 g = 2.72

-1790 kJ/ mol x 2.72 mol = 4869 kJ

b) Here we are asked the mass of octane to produce 1950 kJ of heat knowing that per mol of octane we get 5074.1 kJ, then

1 mol / 5074.1 kJ x 1950 kJ = 0.384 mol

mass C8H18 = 0.384 mol x 114.23 g/mol = 43.86 g

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What is the IUPAC name?

Anastasy [175]

International Union of Pure and Applied Chemistry

4 0

3 years ago

A compound formed from titanium and oxygen has the formula TiO2. Which of the following is true about the ratio of number Ti and

Finger [1]

Answer:

Explanation:

There are some basic laws that guide the combination of elements chemically. These are the law of conservation of mass, law of definite proportion, law of multiple proportion and the law of reciprocal proportion.

For this question, the useful law to use is the law of definite proportion. Here, it is stated that no matter the method of preparation or source of preparation, the elements of a chemical compound are always present in a fixed ratio.

What this means that at any point in time, the compound titanium dioxide contains one atom of titanium and two atoms of oxygen. This means that both atoms are present at all times in a proportion of 1 to 2 .

4 0

4 years ago

Buffer preparation. You wish to prepare a buffer consisting of acetic acid and sodium acetate with a total acetic acid plus acet

Hoochie [10]

Answer:

0.182 moles of acetic acid are needed, this means 10.93 g.

0.318 moles of sodium acetate are needed, this means 26.08 g.

Explanation:

The Henderson–Hasselbalch (H-H) equation tells us the relationship between the concentration of an acid, its conjugate base, and the pH of a buffer:

pH = pka + $log\frac{[A^{-} ]}{[HA]}$

In this case, [A⁻] is the concentration of sodium acetate, and [HA] is the concentration of acetic acid. The pka is a value that can be looked up in literature: 4.76.

From the problem we know that

[A⁻] + [HA] = 250 mM = 0.250 M eq. 1

We use the H-H equation, using the data we know, to describe [A⁻] in terms of [HA]:

5.0 = 4.76 + $log\frac{[A^{-} ]}{[HA]}$

$0.24=log\frac{[A^{-} ]}{[HA]}\\\\10^{0.24}=\frac{[A^{-} ]}{[HA]}\\ 1.74 [HA] = [A^{-}]$ eq.2

Now we replace the value of [A⁻] in eq. 1, to calculate [HA]:

1.74 [HA] + [HA] = 0.250 M

[HA] = 0.091 M

Then we calculate [A⁻]:

[A⁻] + 0.091 M = 0.250 M

[A⁻] = 0.159 M

Using the volume, we can calculate the moles of each substance:

moles of acetic acid = 0.091 M * 2 L = 0.182 moles
moles of sodium acetate = 0.159 M * 2 L = 0.318 moles

Using the molecular weight, we can calculate the grams of each substance:

grams of acetic acid = 0.182 mol * 60.05 g/mol = 10.93 g
grams of sodium acetate = 0.318 mol * 82.03 g/mol = 26.08 g

8 0

3 years ago

Assume that the complete combustion of one mole of glucose, a monosaccharide, to carbon dioxide and water liberates 2870 kJ2870

Lubov Fominskaja [6]

Answer:

number of moles of the compound $\approx$ 53 mole

Explanation:

Given that:

The total energy liberated = - 2870 kJ ( here , the negative sign typical implies the release of energy due to the combustion reaction)

The equation of the reaction can be represented as:

$\mathbf{C_6H_{12}O_6_{(s)} + 6O_{2(g)} \to 6CO_{2(g)}+6H_2O_{(l)}}$

The energy needed to synthesize 1 mole of compound X = - 54.1 kJ.mol

Thus;

The total energy = numbers of moles of compound × Energy needed to synthesize 1 mole of compound X

Making the numbers of moles of the compound the subject; we have;

numbers of moles of compound = $numbers \ of \ moles \ of \ compound = \dfrac{total \ energy }{Energy \ needed \ to \ synthesize \ 1 \ mole \ of \ compound \ X}$ $numbers \ of \ moles \ of \ compound = \dfrac{-2870 \ kJ }{-54.1 \ kJ/mol}$

number of moles of the compound = 53.04990 mole

number of moles of the compound $\approx$ 53 mole to two significant figure

7 0

3 years ago

Metallurgy is the study of _____.

vovangra [49]

Hello,

The answer is "behaviors and properties of metals".

Reason:

The answer is the study of behaviors and properties of metals.

If you need anymore help feel free to ask me!

Hope this helps!

~Nonportrit

5 0

4 years ago

Read 2 more answers