how is the concept of effective nuclear charge used to simplify the numerous electron-electron repulsions in many-electron atom

Paliwanag ang kahalagahan ng papa at ng holy roman emperor sa panahong midieval.

Doss [256]

Explanation:

The Holy Roman Empire (Latin: Sacrum Imperium Romanum; German: Heiliges Römisches Reich), also termed as the First Reich, was a multi-ethnic complex of territories in Western and Central Europe that developed during the Early Middle Ages and continued until its dissolution in 1806 during the Napoleonic Wars.[6] The largest territory of the empire after 962 was the Kingdom of Germany, though it also included the neighboring Kingdom of Bohemia and Kingdom of Italy, plus numerous other territories, and soon after the Kingdom of Burgundy was added. However, while by the end of the 15th century the Empire was still in theory composed of three major blocks – Italy, Germany, and Burgundy – in practice only the Kingdom of Germany remained, with the Burgundian territories lost to France and the Italian territories, ignored in the Imperial Reform, although formally part of the Empire, were splintered into numerous de facto independent territorial entities.[7][8][9][10] The external borders of the Empire did not change noticeably from the Peace of Westphalia – which acknowledged the exclusion of Switzerland and the Northern Netherlands, and the French protectorate over Alsace – to the dissolution of the Empire. By then, it largely contained only German-speaking territories, plus the Kingdom of Bohemia, the southern Netherlands and lands of Carniola. At the conclusion of the Napoleonic Wars in 1815, most of the Holy Roman Empire was included in the German Confederation.

in yr language:

Ang Holy Roman Empire (Latin: Sacrum Imperium Romanum; German: Heiliges Römisches Reich), na tinawag din bilang First Reich, ay isang multi-etniko na kumplikado ng mga teritoryo sa Kanluran at Gitnang Europa na d

3 0

3 years ago

The powder mixture (Cu, Al and Fe) = 10g was oxidized from sufficient chloride acid. 1) What are the possible reactions to the p

Mandarinka [93]

Answer:

1) 2Al + 6HCl ⟶ 2AlCl₃ + 3H₂

Fe + 2HCl ⟶ FeCl₂ + H₂

2) Cu = 2.5 g; Al = 3.5 g; Fe = 4.0 g

Explanation:

1) Possible reactions

2Al + 6HCl ⟶ 2AlCl₃ + 3H₂

Fe + 2HCl ⟶ FeCl₂ + H₂

2) Mass of each metal

a) Mass of Cu

The waste was the unreacted copper.

Mass of Cu = 2.5 g

b) Masses of Al and Fe

We have two relations :

Mass of Al + mass of Fe = 10 g - 2.5 g = 7.5 g

H₂ from Al + H₂ from Fe = 6.38 L at NTP

i) Calculate the moles of H₂

NTP is 20 °C and 1 atm.

$\begin{array}{rcl}pV & = & n RT\\\text{1 atm} \times \text{6.38 L} & = & n \times 0.08206 \text{ L}\cdot\text{atm}\cdot\text{K}^{-1}\text{mol}^{-1} \times \text{293.15 K}\\6.38 & = & 24.06n \text{ mol}^{-1} \\n & = & \dfrac{6.38}{24.06 \text{ mol}^{-1} }\\\\ & = & \text{0.2652 mol}\\\end{array}$

(ii) Solve the relationship

Let x = mass of Al. Then

7.5 - x = mass of Fe

Moles of Al = x/27

Moles of Fe = (7.5 - x)/56

Moles of H₂ from Al = (3/2) × Moles of Al = (3/2) × (x/27) = x /18

Moles of H₂ from Fe = (1/1) × Moles of Fe = (7.5 - x)/56

∴ x/18 + (7.5 - x)/56 = 0.2652

56x + 18(7.5 - x) = 267.3

56x + 135 - 18x = 267.3

38x = 132.3

x = 3.5 g

Mass of Al = 3.5 g

Mass of Fe = 7.5 g - 3.5 g = 4.0 g

The masses of the metals are Cu = 2.5 g; Al = 3.5 g; Fe = 4.0 g

4 0

3 years ago

7. Name the mineral that is found in all 4 foliated metamorphic<br> rocks.

Mazyrski [523]

Explanation:

not sure but I think is quartz or feldspar minerals

4 0

3 years ago

Draw the structure of the major organic product isolated from the reaction of 3-hexyne with hydrogen (1 mol), Lindlar palladium.

ohaa [14]

Answer:

See explanation and image attached

Explanation:

When 1 mole of hydrogen is added to 3-hexyne, the addition occurs on the same face or side of the triple bond to yield cis-2-hexene in the presence of lindlar catalyst which prevents further hydrogenation. This is known as syn addition.

The syn addition is achieved because the hydrogen molecule is first adsorbed on the surface of the palladium metal and is subsequently attached to the same face of the triple bond in 3-hexyne as shown in the image attached to this answer.

6 0

3 years ago

Which of the following substances contain metallic bonds?

devlian [24]

I think it’s C. Copper

3 0

3 years ago