All categories

3 years ago

An atom has the following electron configuration.

Chemistry

2 answers:

vagabundo [1.1K]3 years ago

8 0

Answer: The number of valence electron in the given atom are 5

Explanation:

Valence electrons are defined as the electrons which are present in the outermost shell of an atom. Outermost shell has the highest value of 'n' that is principal quantum number.

For the given electronic configuration: $1s^22s^22p^63s^23p^64s^23d^3$

When an element belongs to d-block, the number of valence electrons are present in $ns,np\text{ and }(n-1)d$ orbitals

Here, n = 4

The electrons in '4s' orbital = 2

The electrons in '3d' orbital = 3

Number of valence electrons = 2 + 3 = 5

Hence, the number of valence electron in the given atom are 5

V125BC [204]3 years ago

3 0

Answer:

Explanation:

The valence electrons are the electrons that are located in the outermost shel of an atom.

Writing the configuration properly, we have:

1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d³

In this atom, there is a total number of 23 electrons. This is a transition metal.

The 4s and 3d orbitals are in the outermost energy levels and so their electrons are valent.

You might be interested in

Explain why space junk is a hazard to an astronats or spacecraft

Pie

Answer:

Space junk is travelling so fast that a collision with an astronaut or a spacecraft could be disastrous.

Explanation:

Space junk orbits the Earth at speeds of about 28 000 km/h.

That's so fast that even an orbiting fleck of paint has enough kinetic energy to cause impact craters on the surface of a spacecraft. They are even more dangerous to an astronaut on a space walk.

Much of the space debris is larger and more dangerous than a fleck of paint.

One rough estimate of the amount of space debris is

Size Number of objects

< 1 cm 200 000 000

1 cm to 10 cm 700 000

> 10 cm 30 000

Satellites, etc. 18 000

The chances of collision are small, but any collision can be disastrous.

3 0

3 years ago

During the titration of a diluted vinegar sample with a sodium hydroxide solution, the volume of sodium hydroxide used was less

lapo4ka [179]

Answer:

B and D could be true

Explanation:

A volume of sodium hydroxide less than expected could occurs for two reasons:

The real concentration of sodium hydroxide was higher than expected or the amount of vinegar added was less than expected:

A. The sodium hydroxide solution had been allowed to stand exposed to the air for a long time prior to the titration. FALSE. A long expose to the air decreases concentration of the NaOH.

B. The volumetric flask used to prepare the diluted vinegar solution was rinsed with water prior to use. TRUE. You add a less amount of vinegar doing you require less amount of NaOH than expected.

C. The burette used to deliver the sodium hydroxide solution was rinsed with water prior to use. FALSE. Thus, you add a less amount of NaOH than expected. To explain the matter, you add more NaOH than expected.

D. The pipette used to deliver the vinegar solution was rinsed with water prior to use. TRUE. Again, you are adding a less amount of Vinegar than expected doing the necessary NaOH during titration less than expected

6 0

3 years ago

A student weighed out a 2.055 g sample of a cobalt chloride hydrate, ConClmpH2O, where n, m, and p are integer values to be dete

topjm [15]

The given mass of cobalt chloride hydrate = 2.055 g

A sample of cobalt chloride hydrate was heated to drive off waters of hydration and the anhydrate was weighed.

The mass of anhydrous cobalt chloride = 1.121 g anhydrate.

The mass of water lost during heating = 2.055 g - 1.121 g = 0.934 g

Converting mass of water of hydration present in the hydrate to moles using molar mass:

Mass of water = 0.934 g

Molar mass of water = 18.0 g/mol

Moles of water = $0.934 g * \frac{1 molH_{2}O }{18 g H_{2}O } =0.0519 mol H_{2}O$

8 0

3 years ago

Sunlight is composed of energy that is visible to humans and energy that is not visible to humans. Which statement describes how

Vilka [71]

Answer:

both forms of energy referred to in the question is light and heat energy

light energy is the visible energy that travels at a known constant speed of 3.0×10^9m/s

while heat energy is the invisible energy that travels in form of radiation at variable speeds

4 0

3 years ago

How does a buffer resist change in ph upon addition of a strong acid?

lora16 [44]

Any buffer exists in this equilibrium

HA <=> $H^+ + A^-$
In a buffer, there is a large reservoir of both the undissociated acid (HA) and its conjugate base ( $A^-$ )

When a strong acid is added, it reacts with the large reservoir of the conjugate base ( $A^-$ ) forming a salt and water. Since this large reservoir of the conjugate base is used, the ph does not alter drastically, but instead resist the pH change.

8 0

3 years ago