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2 years ago

Which example best demonstrates Charles’s law?

Chemistry

2 answers:

Liono4ka [1.6K]2 years ago

6 0

Answer:

Explanation:

The Charles law states that the volume of an ideal gas increases when temperature is increased under constant pressure. The pressure inside the balloon is always equal to the atmospheric pressure. Therefore answer A demonstrate the Charles law.

Assoli18 [71]2 years ago

6 0

Answer:

D. A syringe pulls in air as the plunger is pulled back.

Explanation:

As per Charles’s law

At constant pressure for a given amount of a gas,

Volume is directly proportional to its temperature.

Directly proportional means when one increases the other one too will increase. That is when volume increases temperature too will increase. When volume decreases, temperature too will show a decrease.

Option A tells us that the volume of the hot air balloon increase due to the rise(increase) in temperature as the balloon is heated

Thus the expression is $V \propto T$

$\frac {V}{T} = k$ where k is a constant

When there is a change in the volume and temperature the expression will be

$\frac {V_1}{T_1} = \frac {V_2}{T_2}$

where $V_1$ and $T_1$ are the initial volume and initial temperature and $V_2$ and $T_2$ are the final volume and temperature.

You might be interested in

Which of the following is an indication of a chemical reaction?

vovikov84 [41]

Answer:

All of the above

Explanation:

Their all chemical change

7 0

2 years ago

If 17. 6 g of hcl are used to produce a 14. 5 l solution, what is the ph of the solution?.

kati45 [8]

This problem is providing us with the mass of hydrochloric acid and the volume of solution and asks for the pH of the resulting solution, which turns out to be 1.477.

<h3>pH calculations</h3>

In chemistry, one can calculate the pH of a solution by firstly obtaining its molarity as the division of the moles of solute by the liters of solution, so in this case for HCl we have:

$M=\frac{17.6g*\frac{1mol}{36.46g} }{14.5L} \\\\M=0.0333 M$

Next, due to the fact that hydrochloric acid is a strong acid, we realize its concentration is nearly the same to the released hydrogen ions to the solution upon ionization. Thereby, the resulting pH is:

$pH=-log(0.0333)\\\\pH=1.477$

Which conserves as much decimals as significant figures in the molarity.

Learn more about pH calculations: brainly.com/question/1195974

3 0

1 year ago

Scoring: Your score will be based on the number of correct matches minus the number of incorrect matches. There is no penalty fo

jarptica [38.1K]

Answer:

a. Too close to zero

b. ΔS > 0

c. Too close to zero

d. ΔS < 0

e. ΔS > 0

Explanation:

In order to answer this question we need to compare the change in number of mol in the gas state for the products vs the reactants.

An increase in number moles gas leads to a positive change in entropy. Conversely a decrease will mean ΔS is negative.

Now we can solve the parts in this question.

a. H₂ (g) + F₂ (g) ⇒ 2 HF (g)

We have no change in the number of moles gas products minus reactants. Therefore is too close to zero to decide since there is no change in mol gas.

b. 2 SO₃ ( g) ⇒ 2 SO₂ (g) + O₂ (g)

We have three moles of gas products starting with 2 mol gas SO₂, therefore ΔS is positive.

c. CH₄ (g) + 2 O₂ (g) ⇒ CO₂ (g) + 2 H₂O (g)

Again, we have the same number of moles gas in the products and the reactants (3), and it is too close to zero to decide

d. 2 H₂S (g) + 3 O₂(g) ⇒ 2 H2O (g) + 2 SO₂ (g)

Here the change in number of moles gas is negative ( -1 ), so will expect ΔS < 0

e. 2H₂O₂ (l) ⇒ 2H₂O(l) +- O2(g)

Here we have 1 mol gas and 2 mol liquid produced from 2 mol liquid reactants, thus the change in entropy is positive.

3 0

2 years ago

Sulfur dioxide, SO2(g), can react with oxygen to produce sulfur trioxide, SO3(g), by the following reaction

WITCHER [35]

Answer:

The heat produced is -15,1kJ

Explanation:

For the reaction:

2SO₂+O₂ → 2SO₃

The enthalpy of reaction is:

ΔHr = 2ΔHf SO₃ - 2ΔHf SO₂

As ΔHf SO₃ = -395,7kJ and ΔHf SO₂ = -296,8kJ

ΔHr = -197,8kJ

Using n=PV/RT, the moles of reaction are:

$n = \frac{1,00atm*3,75L}{0,082atmL/molK*298,15K}$ = 0,153 moles of reaction

As 2 moles of reaction produce -197,8kJ of heat, 0,153moles produce:

0,153mol× $\frac{-197,8kJ}{2mol}$ = -15,1kJ

I hope it helps!

8 0

2 years ago

Which statements accurately describe Dmitri Mendeleev’s contributions to the development of the periodic table? Check all that a

Varvara68 [4.7K]

Answer:

Mendeleev produced the first orderly arrangement of known elements.

Mendeleev used patterns to predict undiscovered elements.

Explanation:

Mendeleev produced the first orderly arrangement of known elements and used patterns to predict the undiscovered elements.

Those two statments are true.

For the time being there were some 62 known elements. Before Medeleev some schemes to order part of the elements were proposed, but Medeleev showed the relationship between the atomic mass and the properties of the elements (supports second choice). This arrangement is known as the periodic table.

More importantly, Mendeleev predicted correctly the existance and properties of unknown elements, which is his major contribution: he left blanket spaces which where gradually filled when new elements where discovered (this supports the fourth choice).

The first modern chemistry book was written by Antoine Lavoisier (this discards first option).

Mendeleev ordered the elements by increasing mass number (this discards third choice), which was corrected later by the scientist Henry Moseley, who ordered the elements by increasing atomic number (number of protons).

Isotopes were not known by Mendeleev times, so this discards the last option.

8 0

2 years ago

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