All categories

2 years ago

The existence of discrete (quantized) energy levels in an atom may be inferred from

1 answer:

8 0

<span>It can be inferred from atomic line spectra. These are certain wavelengths of light that atoms give off when they become excited. The energy levels in an atom can be proven to exist from this phenomenon, and furthermore, they can be measured.</span>

You might be interested in

jamie is not sure a new medication will work because it has not had a large test group. Is jamie being creative?

Georgia [21]

Answer:

yes because I wouldn't do it

7 0

2 years ago

In the periodic table which elements typically have similar properties

rosijanka [135]

Elements which appear in the same column have similar properties (periodicity). For example, all of the elements in group XVII (17), the Halogens, all react in a similar fashion; they all like to attract one additional electron and form a -1 anion.

7 0

2 years ago

MgNH4PO4•6H2O loses H2O in a stepwise fashion as it is heated. Between 40 degrees celsius and 60 degrees celsius, the monohydrat

tino4ka555 [31]

Answer:

$\%\ Composition\ of\ phosphorus=20.00\ \%$

Explanation:

The molecular formula of the monohydrate formed = $MgNH_4PO_4.H_2O$

The molecular mass of the monohydrate formed = $Mass_{Mg}+Mass_{N}+6\times Mass_{H}+5\times Mass_O$

So, Mass = 24 + 14 + 6 × 1 + 5 × 16 = 155 g

Mass of phosphorus = 31 g

Thus,

$\%\ Composition\ of\ phosphorus =\frac{Mass_{phosphorus}}{Total\ mass}\times 100$

$\%\ Composition\ of\ phosphorus=\frac{31}{155}\times 100$

$\%\ Composition\ of\ phosphorus=20.00\ \%$

4 0

2 years ago

Draw the mechanism for the addition of methylmagnesium bromide to propanoyl chloride (CH3CH2COCl) to give 2-methyl-2-butanol.

Ghella [55]

Answer:

Reaction mechanism has been given below

Explanation:

Propanoyl chloride contains an electrophilic carbonyl center to give nucleophilic acyl substitution reaction by removing Cl group with a strong nucleophile like methylmagnesium bromide.
Two equivalent of methyl magnesium bromide react with cabonyl center followed by protonation of negatively charged oxygen atom gives 2-methyl-2-butanol.
In the first step, nucleophilic acyl substituion occurs. In the second step, nucleophilic addition occurs. In the third step, protonation occurs.
Reaction mechanism has been shown below.

7 0

2 years ago

In the balanced reaction and using the mole ratio:

NikAS [45]

12 moles are needed because stoichiometry is 1:2

4 0

3 years ago