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3 years ago

What does the Aufbau principle state?

2 answers:

8 0

Hello there!

The correct answer is B. Electrons will be added to an atom starting from the lowest possible level or sublevel.

Hope This Helps You!
Good Luck :)

Sidana [21]3 years ago

3 0

Answer: The correct answer is Option B.

Explanation:

Aufbau principle states that the electron will occupy the lowest energy level first before occupying the higher energy levels.

In filling of electrons, '1s' orbital will be filled first than '2s' orbital because the former has low energy level than the later.

For Example: Filling of electrons in chromium atom.

Chromium is the 24th element of the periodic table and its electronic configuration must be written as: $1s^22s^22p^63s^23p^63d^44s^2$

But the actual configuration for this is $1s^22s^22p^63s^23p^63d^54s^1$

This configuration is an exception to Aufbau's principle as half filled sub-levels is more stable than other configurations.

Hence, the correct answer is Option B.

You might be interested in

I have seven energy levels, but only 1 valence eletron?

Olenka [21]

Answer:

Francium (Fr)

Explanation:

Looking at the periodic table, Francium has 7 energy levels as it is in the 7th Period and is in the 1st Group (meaning it has one electron in the outermost shell) which suggests that it has one valence electron.

Hope this helps and be sure to have a wonderful time ahead at Brainly! :D

3 0

3 years ago

GIVING BRAINLY, 5 STARS, FOLLOW AND HEARTS as majority of substances heat up, they:

melamori03 [73]

Answer:

Expand

Explanation:

When you heat up a substance it expands

3 0

3 years ago

What mass of butane in grams is necessary to produce 1.5×103 kj of heat what mass of co2 is produced?

kari74 [83]

The heat of reaction (i.e. combustion) of butane ( $C_{4} H_{10}$ ) when reacted with oxygen ( $O_{2}$ )  is -2658 kJ/mol butane, and the chemical reaction is given by:

$C_{4} H_{10}$ + $\frac{13}{2} O_{2}$ ---> $4 CO_{2}$ + $5 H_{2}O$

The mass of butane required in the reaction is based on the heat produced by the reaction, which is given to be -1,500 kJ. The minus sign is added because the reaction releases heat (exothermic), which means that the products are in a "lower energy state" than the reactants.

Dividing this with the heat of reaction per mole of butane reacted would give the number of moles butane required. Then, multiplying the answer with the molar mass of butane which is 58 grams/mole, will give the mass of butane required.

Moles of butane = [(-1,500 kJ)/(-2658 kJ/mol butane)]
Moles of butane = 0.5643 moles butane

Mass of butane  = 0.5643 moles butane * 58 grams/mol butane
Mass of butane = 32.73 grams butane

The mass of carbon dioxide ( $CO_{2}$ ) can be determined by multiplying the moles of butane ( $C_{4} H_{10}$ ) with the mole ratio of ( $CO_{2}$ ) produced to the ( $C_{4} H_{10}$ ) reacted, and then with the molar mass of ( $CO_{2}$ ), which is 44 grams/mole.

Mass of carbon dioxide produced
= 0.5643 moles butane * [4 moles $CO_{2}$ / 1 mole $C_{4} H_{10}$ ] * 44 grams/mole $CO_{2}$

Mass of carbon dioxide produced
= 99.32 grams $CO_{2}$

Thus, the mass of butane required is 32.73 grams, and the mass of carbon dioxide produced from the reaction of this amount of butane is 99.32 grams.

4 0

3 years ago

Read 2 more answers

The rate of disappearance of HBr in the gas phase reaction2HBr(g) → H2(g) + Br2(g)is 0.301 M s-1 at 150°C. The rate of appearanc

jok3333 [9.3K]

Answer: 0.151

Explanation:

Rate law says that rate of a reaction is directly proportional to the concentration of the reactants each raised to a stoichiometric coefficient determined experimentally called as order.

$2HBr(g)\rightarrow H_2(g)+Br_2(g$

The rate in terms of reactants is given as negative as the concentration of reactants is decreasing with time whereas the rate in terms of products is given as positive as the concentration of products is increasing with time.

$Rate=-\frac{1d[HBr]}{2dt}=+\frac{1d[H_2]}{2dt}=+\frac{1d[Br_2]}{dt}$

Given: $-\frac{d[HBr]}{dt}]=0.301$

Putting in the values we get:

$\frac{0.301}{2}=+\frac{1d[Br_2]}{dt}$

$+\frac{1d[Br_2]}{dt}=0.151$

Thus the rate of appearance of $Br_2$ is 0.151

8 0

3 years ago

A student dropped a piece of nickel metal into a solution of HCl(aq). He observed the formation of gas bubbles and collected the

omeli [17]

Answer:

a. The student performed the splint test incorrectly. He should of observed a popping sound when the splint was placed in the test tube.

Explanation:

It is given that a student performed an experiment where he dropped a nickel metal in to HCl solution. He observed the reaction and performed a splint test in the test tube that is filled with a gas which is formed while Nickle is dropped into the solution of HCl.

But the experiment that the student performed was incorrect. He must have observed the popping sound when the splint was placed in the test tube.

When the splint was added to the gas splint flared up. The hydrogen gas pops out when exposed to the flame.

$Ni + HCl(aq) = NiCl + H_2$

Thus the correct option is (a).

5 0

3 years ago