Please I need help I really don’t get this lol

Answer:

Mass = 0.084 g

Explanation:

Given data:

Mass of silicon = ?

Number of atoms of silicon = 1.8 × 10²¹ atom

Solution:

Avogadro number:

The given problem will solve by using Avogadro number.

It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.  The number 6.022 × 10²³ is called Avogadro number.

1 mole = 6.022 × 10²³  atoms

1.8 × 10²¹ atom × 1 mole /  6.022 × 10²³  atoms

0.299× 10⁻² mol

0.00299 mol

Mass of silicon:

Mass = number of moles × molar mass

Mass = 0.00299 mol × 28.1 g/mol

Mass = 0.084 g

Answer:

12 protons and 12 neutrons are present in Mg and

38 protons and 50 neutrons are present in Sr

Explanation:

Answer:

For ²⁴Mg

1. Proton number = 12

2. Neutron number = 12

For ⁸⁸Sr:

1. Proton number = 38

2. Neutron number = 50

Explanation:

For ²⁴Mg:

1. Determination of the number of proton.

The atomic number of an element is simply defined as the number protons in the atom of the element. The atomic number of ²⁴Mg is 12 since no two elements have the same atomic number.

Atomic number = 12

Proton number = Atomic number

Proton number = 12

2. Determination of the Neutron number.

Mass number = 24

Proton number = 12

Neutron number =?

Mass number = Proton + Neutron

24 = 12 + Neutron

Collect like terms

Neutron = 24 – 12

Neutron number = 12

For ⁸⁸Sr:

1. Determination of the number of proton.

The atomic number of ⁸⁸Sr is 38.

Atomic number = 38

Proton number = Atomic number

Proton number = 38

2. Determination of the Neutron number.

Mass number = 88

Proton number = 38

Neutron number =?

Mass number = Proton + Neutron

88 = 38 + Neutron

Collect like terms

Neutron = 88 – 38

Neutron number = 50

Explanation:

Agl+hih+356bnh$&56DG hug zero cg hydh hod sir un bucks

Answer:

O, Ca, Zn, Br

Sc, K, Br,

Explanation:

The correct order of the chemical elements from highest to lowest electronegativity is: C. Br, Zn, Sc, Ca, K.

Electronegativity refers to a measure of the ability of an atom of a chemical element to attract any shared pair of electrons.

Generally, the electronegativity of a chemical element typically increases across the period from left to right.

In Chemistry, the electronegativity of some of the chemical element are:

Hence, the order of the chemical elements from highest to lowest electronegativity is:

1. Bromine (Br) = 2.96

2. Zinc (Zn) = 1.65

3. Scandium (Sc) = 1.36

4. Calcium (Ca) = 1.0

5. Potassium (k) = 0.82

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Answer:

The produce large circular currents in all the ocean basins. Currents, The North Equatorial Current, the Gulf Stream, the North Atlantic Current, and the Canary Current.

Explanation:

Answer:

It melts

Explanation:

Answer:

It melts?

Explanation:

Explanation:

Methane is a gas at room temperature but methanol is a liquid because in methane there's London dispersion intermolecular force but in methanol there's H-bond and London dispersion force. H-bond is more stronger than London dispersion force. So, it increases the boiling point of methanol that's why methane is gas at room temperature due to weak attraction of London dispersion force and methanol is liquid.

Methanol has a higher boiling point than methane due to stronger intermolecular forces (IMFs), or attraction between individual molecules. This makes its molecules more difficult to separate, requiring more energy and resulting in a higher boiling point.

An intermolecular force is a force that mediates the interaction of molecules, including electromagnetic forces of attraction or repulsion that act between atoms and other types of neighboring particles, such as atoms or ions.

Intermolecular forces are classified into five types namely,

Between ions and polar dipole molecules, ion-dipole forces exist.

Since of stronger intermolecular forces (IMFs), or attraction between individual molecules, methanol has a higher boiling point than methane.

This makes it more difficult to separate its molecules, requiring more energy and resulting in a higher boiling point.

Thus, this is the reason of using types of intermolecular forces present.

For more details regarding intermolecular forces, visit:

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#SPJ2

Answer:

about 16

Explanation:

its 20 - ( approximately 5)

= approximately 16

Answer:

It should be (C) about 12cm

Volume of Ammonia(NH₃) = 22.4 L

Given

Reaction

3CuO+2NH₃⇒ 3Cu + 3H₂O+ N₂

In the problem, the CuO coefficient should be 3 not 2

M CuO = 80

mass CuO = 120 g

Required

The volume of NH₃

Solution

mol CuO :

[tex]\tt mol=\dfrac{mass}{M}\\\\mol=\frac{120}{80}\\\\mol=1.5[/tex]

From the equation, mol ratio CuO : NH₃ = 3 : 2, so mol NH₃=

[tex]\tt \dfrac{2}{3}\times 1.5=1~mol[/tex]

Assume at STP(0 °C, 1 atm) ⇒1 mol = 22.4 L, then volume of NH₃=22.4 L

Answer:

This molecule is AgN3

Explanation:

Answer:

AgN3

Explanation:

Mass of nitrogen N is given as 24.36 g

Molar mass of nitrogen N= 14 g/mol.

amount of substance in mol of N = mass/molar mass

=24.36 g/ 14 g/mol.

=1.74 mol.

Given mass of silver= 62,64 g.

Molar mass of silver Ag=107.87 g/mol

Number of mols=62.64 g ÷ 107.87 g/mol.

=0.58 mol.

Ratio of number of mol of N and number of mols of Ag = 1.74 mol / 0.58 mol

=3:1

Hence, empirical formula is AgN₃.

Answer:

The light microscope bends a beam of light at the specimen using a series of lenses to provide a clear image of the specimen to the observer.

Cost per mole

Table salt : Rs 0.878

Table sugar : Rs 23.63

Given

Cost table salt (NaCl) = 15/kg

Cost table sugar(sucrose-C12H22O11) = 69/kg

Required

cost per mole

Solution

mol of 1 kg Table salt(NaCl ,MW= 58.5 g/mol) :

[tex]\tt mol=\dfrac{1000~g}{58.5}=17.09~mol=Rs~15\rightarrow 1~mol=Rs~0.878[/tex]

mol of 1 kg Table sugar(C12H22O11 ,MW= 342 g/mol) :

[tex]\tt mol=\dfrac{1000}{342}=2.92~mol=Rs~69\rightarrow 1~mol=Rs~23.63[/tex]

Answer:

24

Explanation:

26-2=24 because when an atoms loses 2 electrons it gains 2+ charge

Answer:

Osmosis

Explanation:

Water is very essential for the body. When we drink water, our blood cells absorbs water from the body. This happen by a process called as osmosis process. Osmosis is type of diffusion process.

Water along with oxygen and carbon dioxide are some of the simple molecules that moves into the blood cell. Osmosis is the process by which water molecules passes into the cell bodies through its semi permeable membrane.    

Answer:

C5H12.

Explanation:

The compound will be C5H12.

Now consider the general formula for the combustion of an alkane;

CnH2n+2 + 3n+1/2O2-----> nCO2 + (n+1) H2O

If we substitute n=5, we have;

C5H12 + 8O2-----> 5CO2 + 6H2O

Hence the answer above.

Answer:

1 mole of Na = mass of 22.99 g, 1 mole of Si = mass of 28.09 g.

Answer:￣ﾉﾞ(｡･∀･)ﾉﾞo(*￣▽￣*)ブ(*￣3￣)╭o(*￣▽￣*)ブ(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭(*￣3￣)╭•)>⌐)↖↗↘↙↜↚↯↟↝↖↔↕↙↘↙↘↘↞↴↯↚↨⇌⇋⇆⇉⇑↶⇋⇋↳¾⁷¼¼⁶⁴⁷⁰⁰⁰⁹⅕⅘⅓⅕⅓⅕⨊⨡⨔⨩⨦⨶⨼⨿⨷⨷⨻⨼⨹₴ The answer is resperitory

Explanation:

Answer:

I'm thinking it might be Element 39: Yttrium, as this is Chemistry.

Explanation:

Answer:

A. the valence electrons

Explanation:

Answer:

The valence electrons

Explanation:

The valence electrons determine an element's properties because chemical properties of each element are determined by the element's electronic configuration and PARTICULARLY by its outermost valence electrons. I hope it helps!

                      ~Good luck

Answer:

Its C

Explanation:

If you think about it logically all the other answers don't make sense A and B are to small of a number And D is to Big of a number

Hope this Helps!!

Answer:

Explanation:

Firstly, let's define what ground and excited state electronic configuration.

Ground state electronic configuration is when the electrons of the atom are in there lowest possible energy level while excited state electronic configuration is when electron(s) have moved to a higher energy level. Examples of these are provided in the options

a. 1s²2s²2p⁴ - This is a ground state electronic configuration (of oxygen) because the electrons are in there lowest possible energy level.

b. This option is not displaying (it is displaying something like an image that isn't loading)

c. 1s²2s²2p³3s¹ - We can see from this that an electron jumped from 2p energy level to 3s (p energy level ought to be completely filled with 6 electrons before another electron moves to the next energy level) meaning the electron is in it's excited state thus this is an excited state electronic configuration (of oxygen).

d. 1s²2s¹2p² - We can see from this also that an electron jumped from the 2s energy level to the 2p energy level (making it 2p² instead of 2p¹ in the ground state). The 2s energy level should ordinarily have 2 electrons. Thus, this is an excited state electronic configuration (of boron).

e. 1s²2s²sp¹ - This is a ground state electronic configuration (of boron) since all the electrons are in there lowest possible energy level.

f. 1s²2s³ - This configuration is impossible because the s energy level should only contain a maximum of 2 electrons, thus impossible to have 3 electrons in the s energy level

Explanation:

hope it helpful ✌️✌️

Answer:

option 1. Two substances in a mixture differ in density and particle size. These properties can be used to separate the substances. These properties can be manipulated in order to have a better separation between the two substances.

Explanation:

Answer:

Two substances in a mixture differ in density and particle size. These properties can be used to separate both of them using the separating funnel or using filtration (filter paper).

Explanation:

Since their densities are different, one substance should float above the other in the mixture which allows for the separating funnel to let the substance sinking below (with the heavier density) to flow out first before changing the beaker to let the lighter substance flow out.

The substance with a bigger particle size would not be able to pass through the filter paper unlike the substance with the smaller particle size as the filter paper's pores is not big enough for it to pass through, separating both substances (with one on the paper and the other outside the filter paper, preferably in the beaker placed below the paper).

Answer:

A - dendrites

B - cell body

C - axon terminal

D - myelin sheath

E - nucleus

Hope that helps.

A-dendrite

B-cell body

C-axon terminal

D-axon

E-nucleus

Answer:

a

Explanation:

Chemical then thermal because the carbon emissions produce heat

Then kinetic because there is energy transfer then electric because that's the finished result

Answer:

mixture

Explanation:

Answer:

Mixture

Explanation:

Answer:

C4H8O4

Explanation:

Let (CH20)x

C=1*12.01=12.01     (12.01, 1.01, 16.00 Avg mass of elements)

H=2*1.01=2.01

O=1*16.00=16.00

12.01 + 2.01 + 16.00 = 30.03

120.12/30,03=4

==> (CH2O)4 = C4H8O4

The molecular formula of the molecule that has an empirical formula of [tex]CH_2O[/tex] is equal to [tex]C_4H_8O_4[/tex].

Given the following data:

Scientific data:

To determine the molecular formula of the molecule that has an empirical formula of [tex]CH_2O[/tex]:

First of all, we would find the molar mass of [tex]CH_2O[/tex]:

[tex]CH_2O =12 +(1\times2)+16\\\\CH_2O =30\;g/mol[/tex]

For molecular formula:

[tex](CH_2O)n = 120.12\\\\30n = 120.12\\\\n=\frac{120.12}{30}[/tex]

n = 4.0

[tex](CH_2O)_4 = C_4H_8O_4[/tex]

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