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3 years ago

Which element is a noble gas? (1) krypton (3) antimony (2) chlorine (4) manganese

Chemistry

2 answers:

Leno4ka [110]3 years ago

8 0

Answer:

Krypton

Explanation:

Maksim231197 [3]3 years ago

5 0

The element from those four that is a noble gas is krypton.

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Lattice energy is Question 4 options: the energy given off when gaseous ions combine to form one mole of an ionic solid the ener

aleksley [76]

Answer:

Lattice energy is the energy required to convert a mole of ionic solid into its constituent ions in the gas phase

Explanation:

Lattice energy is usually calculated by the Born-Haber cycle, from the affinity energies and sublimation ethalphy values. It is used as an estimation of the ionic energy strength between the ions in an ionic compound.

It is defined as the energy needed to broke 1 mol of a given ionic compound into its ions in the gaseous state. For example, the lattice energy for sodium chloride (NaCl) is the energy required to separate 1 mol of solid ionic compound (NaCl(s)) and produce the sodium and chlorine ions in the gas phase: Na⁺(g) and Cl⁻(g).

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3 years ago

Evaluate this statement: Substances are made of two or more types of elements.

wolverine [178]

A MOLECULE IS MADE OF TWO OR MORE ELEMENTS CHEMICALLY COMBINED IS KNOWN AS A COMPUND.

A MOLECULE IS MADE OF TWO ATOMS IS JUST AN ELEMENT.

A MOLECULE MADE OF TWO OR MORE ELEMENTS IS KNOWN AS A COMPUND.

6 0

3 years ago

Extend the aufbau sequence through an element that has not yet been identified, but whose atoms would completely fill 7p orbital

Thepotemich [5.8K]

Answer:

Number of electrons = 118

Electronic configuration: [Rn] 5f¹⁴ 6d¹⁰ 7s² 7p⁶

Explanation:

Given: A chemical element that has completely filled 7p orbital.

According to this, the principal occupied electron shell or the valence shell of such an element is 7p.

⇒ the principal quantum number (n) for the valence shell is 7.

∴ this element belongs to the period 7 of the periodic table.

Also, an element that has completely filled p-orbital belongs to the group 18 of the p-block.

Therefore, an element that belongs to the group 7 and period 18 of the periodic table, should have a completely filled 5f, 6d, 7s and 7p orbitals.

Therefore, the electronic configuration should be: [Rn] 5f¹⁴ 6d¹⁰ 7s² 7p⁶

And, the number of electrons = atomic number of radon (Rn) + 14 + 10 + 2 + 6 = 86 + 32 = 118.

Therefore, the given element has atomic number 118 and has the electronic configuration: [Rn] 5f¹⁴ 6d¹⁰ 7s² 7p⁶. Thus the given element can be Oganesson.

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3 years ago

What is adaptation, and what are some examples of it?

Alja [10]

An adaption is a change or process an organism goes through to become better suited for its environment.

Example: A polar bear having white fur in order to blend in in its environment.

6 0

3 years ago

An element X on reacting with oxygen forms an oxide X2O. this oxide dissolves in water and turns blue litmus red. a) Identify th

galben [10]

Answer:

The unknown element is Carbon.

(a) X is Carbon, its oxide is of acidic nature

(b) C+ O2 → CO2

Explanation:

We are given an unknown element that reacts with oxygen.

X + O2 → XO2

It is given that the oxide XO2 turns blue litmus red which is shown by acids, so XO2 is an acidic oxide. Also X will be a Non metal because Non metallic oxide is Acidic in nature.

The Oxide XO2 is dissolving is water. The oxide upon reacting with water will give an Acid.

XO2 type of oxide is found in the 14th group of the periodic table generally

So we have options like C, Si and Ge as these only have the Acidic oxide.

But when it comes to reactivity with water Only Carbon satisfies the need so the unknown element X is C.

CO2 + H2O → H2CO3 which is an acid.

(a) Element X is Carbon (C), The nature of the compound formed is Acidic.

(b) The reaction given will be as follows

C+ O2 → CO2

Therefore the unknown element is Carbon.

4 0

3 years ago