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3 years ago

Were would you be if all the stars you see are circumpolar

1 answer:

3 0

At the Earth's North Pole, the north celestial pole is directly overhead, and all stars that are visible at all (that is, all stars in the northern celestial hemisphere) are circumpolar. As one travels south, the north celestial pole moves towards the northern horizon

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Which explains why the laws

Brums [2.3K]

Answer:

Explanation:

Scientific laws describe how things work with little to no exception. They do NOT provide an explanation to WHY something occurs.

8 0

3 years ago

Read 2 more answers

What is the expected value for the heat of sublimation of acetic acid if its heat of fusion is 10.8 kJ/mol and its heat of vapor

Dennis_Churaev [7]

Answer:

35.1 kJ/mol is the expected value for the heat of sublimation of acetic acid.

Explanation:

$CH_3COOH(l)\rightarrow CH_3COOH(g)$ ..[1]

Heat of vaporization of acetic acid = $H^o_{vap}=24.3 kJ/mol$

$CH_3COOH(s)\rightarrow CH_3COOH(l)$ ..[2]

Heat of fusion of acetic acid = $H^o_{fus}=10.8 kJ/mol$

Heat of sublimation of acetic acid = $H^o_{sub}=?$

$CH_3COOH(s)\rightarrow CH_3COOH(g)$ ..[3]

[1] + [2] = [3] (Hess's law)

$H^o_{sub}=H^o_{vap}+H^o_{fus}$

$=24.3 kJ/mol+10.8 kJ/mol=35.1 kJ/mol$

35.1 kJ/mol is the expected value for the heat of sublimation of acetic acid.

5 0

3 years ago

What element are diamonds composed of

never [62]

Answer:

diamonds are carbon based and have a giant covalent structure

Explanation:

This is what gives diamonds its strength and rigidity.

Diamonds are different from graphite due to the way the atoms are arranged

3 0

3 years ago

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monatomic ion with a charge of +2 has an electronic configuration of 1s22s22p63s23p6. This ion is a(n) . What is the chemical sy

Debora [2.8K]

Answer: The ion is $Ca^{2+}$ . The chemical symbol of the noble gas this ion is isoelectronic with Kr.

Explanation:

The given electronic configuration is,

$M^{2+}:1s^22s^22p^63s^23p^6$

The number of electrons = 2 + 2 + 6 + 2 + 6 = 18 electrons

As the ion has a charge of +2 , that means it has lost two electrons so the the neutral element will have 2 more electrons i.e 18+2 = 20. The element has atomic number of 20 and the element will be Calcium with electronic configuration of

$M: 1s^22s^22p^63s^23p^64s^2$

Thus the symbol of ion is $Ca^{2+}$ . the nearest noble gas with 18 electrons is Krypton with symbol Kr.

3 0

4 years ago

The phenolic indicator (In-OH)has approximately the same pKa as a carboxylic acid. Which H is the most acidic proton in In-OH? C

Sidana [21]

The –OH+ group is most acidic proton in ln-OH as shown in figure (a). The proton is circled in the figure.

The stabilisation of the conjugate base produced is stabilises due to resonance factor. The possible resonance structures are shown in figure (b).

The acidity of a protonated molecule depends upon the stabilisation of the conjugate base produced upon deprotonation. The conjugate base of ln-OH is shown in figure (a).

The possible resonance structures are shown in figure (b). As the number of resonance structures of the conjugate base increases the stabilisation increases. Here the unstable quinoid (unstable) form get benzenoid (highly stable) form due to the resonance which make the conjugate base highly stabilise.

Thus the most acidic proton is assigned in ln-OH and the stability of the conjugate base is explained.

4 0

3 years ago