All categories

3 years ago

I need an explanation

Chemistry

1 answer:

Rina8888 [55]3 years ago

8 0

The Kelvin scale is an absolute temperature scale, while the Celsius scale is not. When you convert a temperature from Celsius to Kelvin, you add 273 degrees to the temperature. However, when you calculate a temperature change, you get the same number, whether you use the Celsius or the Kelvin scale.

You might be interested in

How much heat is released when 1.4 mol of hydrogen fluoride are produced? H2(g) +F2(g) → 2HF(g) +536kJ (Please show work)

polet [3.4K]

Answer:

375.2 kJ

Explanation:

H₂(g) +F₂(g) → 2HF(g) +536kJ

The information the equation above provides lets us know that when 2 mol of hydrogen fluoride (HF) are produced, 536 kJ of energy (as heat) is produced.

We can then state a rule of three:

2 mol HF -------- 536 kJ

1.4 mol HF --------- X

And solve for X:

X = 1.4 mol * 536 kJ / 2 mol

X = 375.2 kJ

7 0

3 years ago

Which of the following you is true for a limiting reactant

skad [1K]

Answer:

C) The limiting reactant has the lowest ratio of moles available / coefficient in the balanced equation.

Explanation:

Please, find attached a complete question to determine which of the statements is or are true for a limiting reactant in a chemical equation.

First, remember that the limiting reactant is the substance that is consumed completely while the excess reactant is the substance that does not react completely.

The limiting reactant is found comparing the stoichiometry ratio and the actual ratio between the reactants.

The stoichiometry ratio is found using the coefficientes of the chemical equation.

For illustration, assume the general chemical equation:

$aA+bB\rightarrow cC+dD$

The stoichiometric ratio of the reactants is:

$a\text{ }moles\text{ }of\text{ }A/b\text{ }moles\text{ }of\text{ }B$

If the ratio of the available moles of substance A to the available moles of substance B is greater than the stoichiometric ratio, it means that there are more moles of the substance A than what is needed to react with the available moles of substance B, then A will be in excess and B will B the limiting reactant.

If, on the contrary, the ratio of the available moles of substance A to the available moles of substance B is is less than the stoichiometric ratio, then substance A is less than the necessary to make the all the moles of substance B react, meaning that the substance A will limit the reaction (it will be consumed completely), while the substance B will be in excess.

As for the options:

A) The limiting reactant is has the lowest coefficient in a balanced equation.

This is false, since it is not the magnitude of the coefficiente what determines the limiting reactant, but the comparison of the ratios.

B) The limiting reactant is the reactant for which you have the fewest number of moles.

This is false because it is not the number of moles what determines the limiting reactant , but the comparison of the ratios.

C) The limiting reactant has the lowest ratio of moles available / coefficient in the balanced equation.

This is true as proved below.

The stoichiometric ratio of the reactants is:

$a\text{ }moles\text{ }of\text{ }A/b\text{ }moles\text{ }of\text{ }B$

The actual ratio is:

$available\text{ }moles\text{ }of\text{ }A/available\text{ }moles\text{ }of\text{ }B$

Assume the first ratio is less than the second (which describes when the substance A is in excess and the limiting reactant is the substance B).

$a\text{ }moles\text{ }of\text{ }A/b\text{ }moles\text{ }of\text{ }B$

Change the relation to show the ratios of moles available of each substance to the cofficient in the chemical equation:

$available\text{ }moles\text{ }of\text{ }B/b\text{ }moles\text{ }of\text{ }B$

Then, in the scenary that the limiting reactant is the substance B, the ratio of the left is lower than the ratio of the right, which is the same that limiting reactant has the lowest ratio of moles available / coefficient in the balanced equation.

D) The limiting reactant has the lowest ratio of coefficients in the balanced eqution/moles available.

This ratio is the inverse of the ratio of the previous statement, thus the relation is inverse, and, since the previous statement was true, this statement is false.

3 0

3 years ago

Carlos has a 1.2 meter long piece of wood. He wants to cut it into 3 equal lengths. How long should each piece be in millimeters

zhenek [66]

There are 1,000 mm in a meter so times 1.2 by 1,000 and you get 1,200.
Now since he wants it in three equal pieces divide 1,200/3 and you get 400.
So your answer is: 400 mm

6 0

2 years ago

How many moles of C3H8 will be produced from 75 moles of CO2?C3H8 + 5 O2 → 3 CO2 + 4 H2O

levacccp [35]

25 moles of C3H8 will be produced from 75 moles of CO2.

<h3>Mole calculation</h3>

To find the value of moles of a product from the number of moles of a reactant, it is necessary to observe the stoichiometric ratio between them:

$C_3H_8 + 5 O_2 = > 3 CO_2 + 4 H_2O$