the melting point of scandium fluoride is 1552°c, explain why scandium fluoride has a high melting point.

What happened to the volume of gas when the syringe was exposed to various temperature conditions? Using the concepts explored i

rewona [7]

Answer:

Thus, when the volume of the gas is exposed to a temperature above -273.15 K, the volume increases linearly with the temperature.

Explanation:

The expression for Charles's Law is shown below:

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

This states that the volume of the gas is directly proportional to the absolute temperature keeping the pressure conditions and the moles of the gas constant.

<u>Thus, when the volume of the gas is exposed to a temperature above -273.15 K, the volume increases linearly with the temperature. </u>

<u>For example , if the temperature of the gas is reduced to half, the volume also reduced to half. </u>

<u>At -273.15 K, according to Charles's law, it is possible to make the volume of an ideal gas = 0.</u>

5 0

1 year ago

The activation energy for the reaction NO2(g)+CO(g)⟶NO(g)+CO2(g) is Ea = 375 kJ/mol and the change in enthalpy for the reaction

HACTEHA [7]

Answer: 625 kj/mol

Explanation:

As shown below this expression gives the activation energy of the reverse reaction:

EA reverse reaction = EA forward reaction + | enthalpy change |

1) The activation energy, EA is the difference between the potential energies of the reactants and the transition state:

EA = energy of the transition state - energy of the reactants.

2) The activation energy of the forward reaction given is:

EA = energy of the transition state - energy of [ NO2(g) + CO(g) ] = 75 kj/mol

3) The negative enthalpy change - 250 kj / mol for the forward reaction means that the products are below in the potential energy diagram, and that the potential energy of the products, [NO(g) + CO2(g) ] is equal to 375 kj / mol - 250 kj / mol = 125 kj/mol

4) For the reverse reaction the reactants are [NO(g) + CO2(g)], and the transition state is the same than that for the forward reaction.

5) The difference of energy between the transition state and the potential energy of [NO(g) + CO2(g) ] will be the absolute value of the change of enthalpy plus the activation energy for the forward reaction:

EA reverse reaction = EA forward reaction + | enthalpy change |

EA reverse reaction = 375 kj / mol + |-250 kj/mol | = 375 kj/mol + 250 kj/mol = 625 kj/mol.

And that is the answer, 625 kj/mol

4 0

2 years ago

What is the simplest formula of a compound if a sample of the compound contains 0.221 mol X, 0.442 mol Y, and 0.884 mol Z? chemP

Gnoma [55]

Answer:

XY₂Z₄

2.35 mol Z

Explanation:

A sample of the compound contains 0.221 mol X, 0.442 mol Y, and 0.884 mol Z. We can find the simplest formula (empirical formula) by <em>dividing all the numbers of moles by the smallest one</em>.

X: 0.221/0.221 = 1

Y: 0.442/0.221 = 2

Z: 0.884/0.221 = 4

The simplest formula is XY₂Z₄.

The molar ratio of X to Z is 1:4. The moles of Z in a sample that contained 0.588 moles of X is:

0.588 mol X × (4 mol Z/1 mol X) = 2.35 mol Z

6 0

1 year ago

Read 2 more answers

How many values of ml are allowed for an electron in a 5f subshell??

VladimirAG [237]

There are 7 values of ml are allowed for an electron in a 5f subshell namely: -3 -2, -1, 0, +1, +2, +3

<h3>Further explanation</h3>

In an atom, there are energy levels in the shell and subshell.This energy level is expressed in terms of electron configurations.

Writing the electron configuration starts from the lowest to the highest subshell's energy level. There are 4 sub-shells in an atom's shell, namely s, p, d, and f. The maximum number of electrons for each subshell is

s: 2 electrons
p: 6 electrons
d: 10 electrons and
f: 14 electrons

Electron filling in subshells using the following sequence:

1s², 2s², 2p⁶, 3s², 3p⁶, 4s², 3d¹⁰, 4p⁶, 5s², 4d¹⁰, 5p⁶, 6s², etc.

Each sub-shell also has orbitals drawn in the form of a square box in which there are electrons symbolized by half arrows.

Each orbital in an atom consists of 4 quantum numbers

n is the principal quantum number.
l is the angular momentum / azimuthal quantum number
ml, the magnetic quantum number
ms, the electron-spin quantum number

Value of n: positive integer

value of l: s = 0, p = 1, d = 2, f = 3

ml value: between -l to + l

ms value: +1/2 or -1/2

Determination of electron configurations based on principles:

1. Aufbau: Electrons occupy orbitals of the lowest energy level
2 Hund: electron fills orbitals with the same energy level
3. Pauli: there are no electrons that have 4 equal quantum numbers

So for 5f orbitals, the value of a possible quantum number is

n = 5;

l = 3 (f = 3);

m = -3 -2, -1, 0, +1, +2, +3;

s = + - 1/2

<h3>Learn more</h3>

the locations and properties of two electrons

brainly.com/question/2292596

It's sublevel

brainly.com/question/4520082

a possible full set of quantum numbers

brainly.com/question/5389767

Keywords: orbitals, subshells, quantum numbers

8 0

2 years ago

Read 2 more answers

A 25.0-g sample of ice at -6.5oC is removed from the freezer and allowed to warm until it melts. Given the data below, select al

alukav5142 [94]

Answer:

B, D

Explanation:

The strategy here is to realize that the ice will be taken from -6.5 ºC to OºC where it will melt.

Lets call q₁ the heat required to bring the ice to 0ºc, q₂ the heat required to bring the phase change from solid to liquid.

q₁ is calculated from the expression

q₁ = s x m x ΔT where m is the mass, s the specific heat of ice ( 2.09 J/gºC ) and ΔT the change in temperature.

q₂ the fusion enthalpy change is calculated from the expression:

q₂ = C x ΔT

where C is the specific heat for the phase change , in this case named AH given in kJ/mol.

We are given all the data needed to calculate q₁, q₂ and qtotal ( q₁ + q₂ )

q₁ = 25.0 g x ( 2.09 J/gºC) x ( 0 - ( -6.5 ºC ) )

q₁ = 339.6 J = 0.339 kJ

q₂ = (25 g/ 18 g/mol) x 6.02 kJ/mol = 1.39 x 6.02 kJ = 8.36 kJ

qtotal = 0.339 kJ + 8.36 kJ = 8.70 kJ

with these calculations, we can now proceed to answer the question:

(a) False AH is theheat capacity for the melting.

(b) True as we determined above

(c) False we only have one phase change, from solid (ice) to liquid

(d) True as calculated above

(e) False as determined in our calculations

7 0

2 years ago

the melting point of scandium fluoride is 1552°c, explain why scandium fluoride has a high melting point.​

the melting point of scandium fluoride is 1552°c, explain why scandium fluoride has a high melting point.