Why does celsium have a lower first ionzation energy than rubidiumn.

The melting points for the compounds li2s, rb2s, and k2s are 900°c, 530°c, and 840°c, respectively. list these three compounds i

Mila [183]

Answer: The order of increasing lattice energy is $Li_2S>K_2S>Rb_2S$

Explanation: Lattice energy is defined as the energy required to break the intermolecular force that is responsible for the formation of a lattice.

Melting point is defined as the temperature at which solid gets converted into liquid due to the weakening of the bonds in the solid form.

Relation between lattice energy and Melting point:

The relationship between these two is direct.

$\text{Lattice energy}\propto \text{Melting point}$

More the melting point of a compound, more will be its lattice energy.

Order of increasing Lattice energy will be:

$Li_2S>K_2S>Rb_2S$

7 0

3 years ago

Select the correct answer.

Alenkasestr [34]

Answer:

D

Explanation:

The unit used to measure atomic mass is the atomic mass unit (amu). A single amu is equivalent to 1/12 the mass of an atom from the carbon-12 isotopIsotopes with different numbers of protons and neutrons will have an actual mass slightly different from the atomic mass calculated in atomic mass units.

4 0

1 year ago

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Un mol de Neón ocupa un volumen de 5 lt y una temperatura 300°K, cuál será su volumen si la temperatura disminuye en 50 °K, P y

Anna [14]

Answer:

No hoblo englas

Explanation:

7 0

2 years ago

HELP WITH CHEMISTRY PLEASE!

maria [59]

Answer:

1) 1.52 atm.

2) 647.85 K.

3) 20.56 L.

4) 1.513 mole.

5) 254.22 K = -18.77 °C.

Explanation:

In all this points, we should use the law of ideal gas to solve this problem: PV = nRT.
Where, P is the pressure (atm), V is the volume (L), n is the number of moles, R is the general gas constant (0.082 L.atm/mol.K), and T is the temperature (K).

1) In this point; n, R, and T are constants and the variables are P and V.

P and V are inversely proportional to each other that if we have two cases we get: P1V1 = P2V2.

In our problem:

P1 = ??? (is needed to be calculated) and V1 = 45.0 L.

P2 = 5.7 atm and V2 = 12.0 L.

Then, the original pressure (P1) = P2V2 / V1 = (5.7 atm x 12.0 L) / (45.0 L) = 1.52 atm.

2) In this case, n and R are the constants and the variables are P, V, and T.

P and V are inversely proportional to each other and both of them are directly proportional to the temperature of the gas that if we have two cases we get: P1V1T2 = P2V2T1.

In our problem:

P1 = 212.0 kPa, V1 = 32.0 L, and T1 = 20.0 °C = (20 °C + 273) = 293 K.

P2 = 300.0 kPa, V2= 50.0 L, and T2 = ??? (is needed to be calculated)

Then, the temperature in the second case (T2) = P2V2T1 / P1V1 = (300.0 kPa x 50.0 L x 293 K) / (212.0 kPa x 32.0 L) = 647.85 K.

3) In this case, P, n and R are the constants and the variables are V, and T.

V and T are directly proportional to each other that if we have two cases we get: V1T2 = V2T1.

In our problem:

V1 = 25.0 L and T1 = 65.0 °C + 273 = 338 K.

V2 = ??? (is needed to be calculated) and T2 = 5.0 °C + 273 = 278 K.

Herein, there is no necessary to convert T into K.

Then, the volume in the second case (V2) = V1T2 / T1 = (25.0 L x 278 °C) / (338 °C) = 20.56 L.

4) We can get the number of moles that will fill the container from: n = PV/RT.

P = 250.0 kPa, we must convert the unit from kPa to atm; 101.325 kPa = 1.0 atm, then P = (1.0 atm x 250.0 kPa) / (101.325 kPa) = 2.467 atm.

V = 16.0 L.

R = 0.082 L.atm/mol.K.

T = 45 °C + 273 = 318 K.

Now, n = PV/RT = (2.467 atm x 16.0 L) / (0.082 L.atm/mol.K x 318 K) = 1.513 mole.

5) In this case, V, n and R are the constants and the variables are P, and T.

P and T are directly proportional to each other that if we have two cases we get: P1T2 = P2T1.

In our problem:

P1 = 2200.0 mmHg and T1 = ??? (is needed to be calculated) .

P2 = 2700.0 mmHg and T2 = 39.0 °C + 273 = 312.0 K.

Herein, there is no necessary to convert P into atm.

Then, the temperature in the morning (T1) = P1T2 / P2 = (2200.0 mmHg x 312.0 K) / (2700.0 mmHg) = 254.22 K = -18.77 °C.

6 0

3 years ago

Read 2 more answers

During which time interval does the substance exist as both a liquid and a solid

Inessa [10]

The Chemistry Regents is one of the four science Regents exams. The other three are Earth Science, Living Environment, and Physics. You'll need to pass at least one of these four exams to graduate high school.

8 0

2 years ago