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Answer:

1. linear (A)

2. trigonal-planar (C)

3. tetrahedral (B)

4. linear (A)

Explanation:

Just did it on Edge 2020

The shape of a molecule can be predicted from the number of electron pairs that surround the central atom in the molecule.

The Valence Shell Electron Pair repulsion theory gives us a basis for predicting the shape of molecules. The shape of a molecule can be predicted from the number of electron pairs that surround the central atom in the molecule.

In the image shown, We can see that in HCN , carbon is the central atom and is surrounded by two atoms and no lone pairs. Since there are two electron domains around the central atom, the molecule is linear.

In the second structure, BH3 has boron as its central atom. Three electron domains surround the central atom hence the molecule is trigonal planar.

Learn more: https://brainly.com/question/25249351

Answer:

number of valence electrons

Explanation:

elements in the same group has same number of valence electrons

Answer:

Explanation:

To find the number of moles in a substance given it's number of entities we use the formula

[tex]n = \frac{N}{L} \\ [/tex]

where n is the number of moles

N is the number of entities

L is the Avogadro's constant which is

6.02 × 10²³ entities

From the question we have

[tex]n = \frac{5.25 \times {10}^{25} }{6.02 \times {10}^{23} } \\ = 87.2093023...[/tex]

We have the final answer as

Hope this helps you

Answer:

Explanation:

The density of a substance can be found by using the formula

[tex]density = \frac{mass}{volume} \\ [/tex]

From the question

mass = 21.7 kg = 21700 g

volume = 5.78 cm³

We have

[tex]density = \frac{21700}{5.78} \\ = 3754.3252...[/tex]

We have the final answer as

Hope this helps you

Answer:

See Below.

Explanation:

This is a conversion problem:

Using the molar mass of Gold (given in a periodic table) which is 196.97g/mol

you have

[tex](3.60*10^-5 g) *\frac{1moles}{196.97g}[/tex]

you always arrange the equation in a way to cancel whatever you don't want (grams) and leave what you do want (moles). Here grams cancel (top and bottom), so you're left with:

[tex]\frac{(3.60*10^-5 g) *(1)}{196.97} = 1.83*10^-7[/tex] moles of Gold

Answer:the positive ionic radius is smaller than the neutral atomic radius

Explanation:

Answer:The positive ionic radius is smaller than the neutral atomic radius.

Explanation: just took the test

Answer:

6. 53 is the answer. Hope this helps:)

The number of d electrons that an atom of atomic number 53 possess are 20. Thus, the correct option for this question is 5.

An atomic number may be defined as the number of protons in the nucleus of an atom that significantly represents the characteristic of a chemical element and determines its specific place in the modern periodic table.

According to the modern periodic table, an element that has an atomic number of 53 is known as Iodine. Its electronic configuration is [tex]1s^2, 2s^2, 2p^6, 3s^2, 3p^6, 4s^2, 3d^1^0, 4p^6, 5s^2, 4d^1^0, 5p^5[/tex]. Thus, according to this electronic configuration, the total number of d electrons are [tex]3d^1^0 and 4d^1^0[/tex].

Therefore, the number of d electrons that an atom of atomic number 53 possess are 20. Thus, the correct option for this question is 5.

To learn more about Electronic configuration, refer to the link:

https://brainly.com/question/26084288

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Answer:

13.5 moles of Ne

Explanation:

1 mole of any gas contains  6.02 x 10²³ atoms of gas

6.02 x 10²³ atoms of neon is equal to 1 mole of neon .

8.15 x 10²⁴ atoms of neon is equal to  1 x 8.15 x 10²⁴ / 6.02 x 10²³ moles

= 8.15 x 10²⁴ / 6.02 x 10²³ mole o neon

= 13.5 moles of Ne .

Answer:

721.9 grams

I hope this helps!

Answer:

Explain that unlike sound, light waves travel fastest through a vacuum and air, and slower through other materials such as glass or water.

Explanation:

Hope this helped.

Answer:

empty space

Explanation:

Answer:

B.  thermal conductivity

Explanation:

They physical property being tested during the fourth step is the thermal conductivity of the materials.

Thermal conductivity is the ability of a body to transmit heat energy from one place to another.

Answer:

The heat is transferred from your hand to the ice, this is because, as we know, heat gets transferred from a hot object to a colder object.

In this case, our hand is clearly hotter than the ice cube.

Therefore, the heat is transferred from your hand to the ice cube.

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Thank You!!

Answer:

1) 3Fe + 2O(2, this is the subscript) - Fe(3)O(4)

2) 2Sr + O(2) - 2SrO

3) Sn + 2NaOH - Na(2)SnO(2) + H(2)

4) 2K + Br(2) -2KBr

5) 2C(8)H(18) + 25O(2) - 16CO(2) + 18H(2)O

Answer:

"Like when people say like im a party fowl but I'm like OMg, I'm like the reason everyone loves the 4th of July like I am 4th of July.

Explanation:

As magnesium ignites easily in air and burns with a bright light, it's used in flares, fireworks and sparklers. I imagine Magnesium talks like a valley girl lol.

Answer:

Oxygen has an atomic number of 8 , and the mass number of an atom is the sum of its atomic number plus its neutron number. We got the mass as 16 units, and so it'll have 16−8=8 neutrons.

Explanation:

Answer:

0.000037 cm is 370 nanometers

Explanation:

Answer:

Explanation:

Answer: The answer would be 158,200

Explanation:

when water is in liquid form and the temperature DROPS it becomes solid ice the process is melting , freezing and evaporation this goes in a circle

Answer:

02

Explanation:

all the other options given are compounds

The volume of cylinder = 7.948 cm³

Further explanation

Volume is a derivative quantity derived from the length of the principal

The unit of volume can be expressed in liters or milliliters or cubic meters

The volume of the aquarium is almost the same as the beam namely:

V = length x width x height

The volume of a cylinder can be formulated :

[tex]\tt V=\pi.r^2.h[/tex]

r = radius

h = height

Diameter of cylinder = 1.25 cm

radius=r :

[tex]\tt \dfrac{1.25}{2}=0.625~cm[/tex]

[tex]\tt V=\pi\times 0.625^2\times 6.48\\\\V=\boxed{\bold{7.948~cm^3}}[/tex]

Answer:

B.) The sound waves are reflected.

Explanation:

On edge,

i also answered so the other person could get the brainliest

Answer:

b

Explanation:

Answer:

KOH+Mg(NO3)2

Explanation:

The double replacement reaction will result in:

2KOH(aq) + Mg(NO3)2[tex]\\[/tex](aq)--> 2KNO3(aq) + Mg(OH)2(s)

Solubility rules prove that Mg+OH^- is insoluble and will result in a precipitate (solid)

Answer: Conduction

Explanation:

Answer:

A, True

Explanation:

Answer:

The Flux N_B = 0

Explanation:

So, we are given the following set of data or parameters which is going to help in solving this particular Question. So, let us take each at a time;

=> "An ammonia (A)-water (B) solution at 278 K and 4.0 mm thick is in contact at one surface with an organic liquid at this interface."

=>" 2.0 wt 'Yo ammonia (density of aqueous solution is 991.7 kg/m3) and the concentration of ammonia in water at the other end of the film 4.0 mm away is 10 wt % (density of 961.7 kg/m3). ''

With the information above, we can determine the N_A(which the question did not specify that we should calculate).

For the value of N_B, it will be equals to zero(0) because the insolubility of water in organic solvent.

Answer:

Molecular Mass

Explanation:

It's asking for the numerical quantity. That quantity would be the Molecular Mass. Take the sample mass and divide it by the molecular mass to get the number of moles.

(14g N * 2) + (1g H *4) = 32g / mol of N2H4

To get # of moles, divide the sample mass by the molecular mass

25g / 32g = 0.78125 moles