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Answer:number of protons in the nucleus and number of electrons in the different shell                                                                                                    

explained : determine the position in the periodic table. ... Their position is decided by their Atomic Number which is the number of protons in the nucleus of the atom.

Answer:

a

Explanation:

a is the 100% correct answer

Answer:

Explanation:

Molar mass of C4H10 = 12x 4 + 1 x 10= 48+ 10=58g.

Also note that molar mass of a substance is equivalent to Avogadro's number (6.02 X 10^-23)

Hence,

6.02 X 10^-23 molecules of ethane was burned in 58g of ethane

So, 4.10 X 10^24 molecules of ethane will burn in xg of ethane.

Cross multiply:

6.02 X 10^-23x = 58 X 4.10 X 10^24

6.02 X 10^-23x = 2.378 X 10 ^26

Dividing both sides by the coefficient of 'x'

x = 2.378 X 10^26/(6.02X 10^-23)

x = 3.95 X10^48g approximately

x = 4.0 X 10^48g

Or

Mole = number of elementary

particless / Avogadro's number

Where,

No of elementary particles= 4.10 X 10^24 molecules

Avogadro's number= 6.02 x 10^-23

Therefore,

Mole = 4.10 X 10^24/ (6.02 X 10^-23)

= 6.81 X 10^ 46 moles.

But mole = mass / molar mass

Mass = mole x molar mass

where

Molar mass of C4H10 = 12x 4 + 1 x 10= 48+ 10=58g/mol

Mass= 6.81 X 10^46 X 58

= 3.95 X 10^48g approximately

= 4.0 X 10^ 48g.

Thanks

Answer:

It is made of atoms that are covalently bonded together.

Explanation:

For example the carbonate ion CO3++.

The carbon and oxygen atoms are held together by covalent bonds.

Answer:

"It is made of atoms that are covalently bonded together." (C)

Explanation:

Polyatomic ion is made of three atoms that are covalently bonded together

Edg. 2020 :)

Answer:

A disproportionation redox reaction  

Explanation:

1. Assign an oxidation number to every atom in the equation

[tex]2\stackrel{\hbox{$\mathbf{+4}$}}{\hbox{N}}\stackrel{\hbox{-2}}{\hbox{O }}_{2} + 2\stackrel{\hbox{-2}}{\hbox{O}}\stackrel{\hbox{+1}}{\hbox{H}^{-}} \longrightarrow \, (\stackrel{\hbox{$\mathbf{+3}$}}{\hbox{N}}\stackrel{\hbox{-2}}{\hbox{O }}_{2})^{-} + (\stackrel{\hbox{$\mathbf{+5}$}}{\hbox{N}}\stackrel{\hbox{-2}}{\hbox{O}_{3}})^{-} +\stackrel{\hbox{+1}}{\hbox{H}}_{2}\stackrel{\hbox{-2}}{\hbox{O}}[/tex]

2. Identify the atoms that change their oxidation number

N in NO₂: +4 ⟶ +3 in NO₂⁻

N in NO₂: +4 ⟶ +5 in NO₃⁻

3. Identify the type of change

This is a disproportionation — a reaction in which one substance is simultaneously oxidized and reduced.

Answer:

D

Explanation:

Answer:

Explanation:

Answer: When a chemical reaction occurs, _____.

a phase change takes place

the physical and chemical properties of the products are different from the reactants

Explanation:

A chemical change is like dynamite exploding or iron rusting. It's an actual change in the chemical makeup resulting in a new product

A chemical reaction results in the production of new substances with physical and chemical properties that are different from the reactants, unlike a physical change which does not alter the molecular structure of the substance.

When a chemical reaction occurs, the physical and chemical properties of the products are different from the reactants. A chemical reaction involves a change in the composition of the substances in question where bonds between atoms are broken and/or formed, resulting in the production of new substances. These new products exhibit different physical and chemical properties such as melting point, color, taste, etc. This is in contrast to a physical change which only affects the appearance or form of a substance without altering its molecular structure. Chemical changes are often more difficult to reverse than physical changes. For example, combining hydrogen and oxygen to produce water is a chemical change because it results in the formation of a new substance with different properties than those of the individual reactants.

Answer:

CCl4- tetrahedral bond angle 109°

PF3 - trigonal pyramidal bond angles less than 109°

OF2- Bent with bond angle much less than 109°

I3 - linear with bond angles = 180°

A molecule with two double bonds and no lone pairs - linear molecule with bond angle =180°

Explanation:

Valence shell electron-pair repulsion theory (VSEPR theory) helps us to predict the molecular shape, including bond angles around a central atom, of a molecule by examination of the number of bonds and lone electron pairs in its Lewis structure. The VSEPR model assumes that electron pairs in the valence shell of a central atom will adopt an arrangement which tends to minimize repulsions between these electron pairs by maximizing the distance between them. The electrons in the valence shell of a central atom are either bonding pairs of electrons, located primarily between bonded atoms, or lone pairs. The electrostatic repulsion of these electrons is reduced when the various regions of high electron density assume positions as far apart from each other as possible.

Lone pairs and multiple bonds are known to cause more repulsion than single bonds and bond pairs. Hence the presence of lone pairs or multiple bonds tend to distort the molecular geometry geometry away from that predicted on the basis of VSEPR theory. For instance CCl4 is tetrahedral with no lone pair and four regions of electron density around the central atom. This is the expected geometry. However OF2 also has four regions of electron density but has a bent structure. The molecule has four regions of electron density but two of them are lone pairs causing more repulsion. Hence the observed bond angle is less than 109°.

Answer:

C

Explanation:

You can see in the chemical equation that 7 [tex]O_{2}[/tex] are used up to produce 6[tex]H_{2}O[/tex]

Answer:

0.06 kg

Explanation:

Given data:

Mass of frisbee = ?

Velocity of frisbee  = 11 m/s

Energy of frisbee = 3.6 j

Solution:

K.E = 1/2 mv²

Now we will put  the values in this formula.

3.6 J = 1/2 m(11m/s)²

3.6 j = 0.5 ×121m²/s² × m

3.6 j = 60.5 m²/s² × m

m = 3.6 j/60.5 m²/s²

m= 0.06 j.m⁻².s²

j = Kg.m².s⁻²

m= 0.06 Kg.m².s⁻² .m⁻².s²

m = 0.06 kg

Answer: 500L

Explanation:

No of moles= volume× molarity/1000

No of moles =0.5moles

Volume=?

Molarity of a gas at stp = 1M

Stp means standard temperature and pressure

No of moles = volume ×molarity/1000

Substitute the values

0.5=volume×1/1000

Cross multiply

Volume = 1000×0.5

Volume = 500L

The volume is 500L

Answer:

[tex]39 ^\circ C[/tex]

Explanation:

Given,

V₁ = 18.5 L

T₁ = 18.5° C = 273 + 18.5 = 291.5 K

V₂ = 19.8 L

T₂ = ?

Pressure is constant

Using ideal gas equation

[tex]\dfrac{V_1}{T_1}=\dfrac{V_2}{T_2}[/tex]

[tex]\dfrac{18.5}{291.5}=\dfrac{19.8}{T_2}[/tex]

[tex]T_2 = 312 K[/tex]

[tex]T_2 = 312 -273 =39 ^\circ C[/tex]

The temperature when the chamber has a volume of 19.8 L should be considered as the 39 degrees.

Since

V₁ = 18.5 L

T₁ = 18.5° C = 273 + 18.5 = 291.5 K

V₂ = 19.8 L

So here the final temperature should be

V1/T1 = V2/T2

18.5 L/291.5 = 19.8 / T2

So T2 = 312 k

= 312 - 273

= 39 degrees

hence, The temperature when the chamber has a volume of 19.8 L should be considered as the 39 degrees.

Learn more about temperature here: https://brainly.com/question/4417455

Answer:

i believe this is the answer The most common example is the molar volume of a gas at STP (Standard Temperature and Pressure), which is equal to 22.4 L for 1 mole of any ideal gas at a temperature equal to 273.15 K and a pressure equal to 1.00 atm.

Explanation:

Answer:

V₁  = 10 mL

Explanation:

Given data:

Initial volume of HCl = ?

Initial molarity = 3.0 M

Final molarity = 0.10 M

Final volume = 300.0 mL

Solution:

Formula:

M₁V₁  =  M₂V₂

M₁ = Initial molarity

V₁  =  Initial volume of HCl

M₂ =Final molarity

V₂ = Final volume

Now we will put the values.

3.0 M ×V₁  =  0.10 M×300.0 mL

3.0 M ×V₁  = 30 M.mL

V₁  = 30 M.mL /3.0 M

V₁  = 10 mL

Answer:

Mass = 14.64 g

Explanation:

Given data:

Volume of solution = 1.25 L

Molarity of Solution = 0.15 M

Mass of CaF₂ = ?

Solution:

Molarity is used to describe the concentration of solution. It tells how many moles are dissolve in per litter of solution.

Formula:

Molarity = number of moles of solute / L of solution

We will calculate the number of moles of CaF₂ and then determine the mass by using number of moles.

0.15 M =  number of moles of solute / 1.25 L

number of moles of solute = 0.15 M ×  1.25 L

number of moles of solute = 0.1875 mol/L × L

number of moles of solute = 0.1875 mol

Mass in gram:

Mass = number of moles × molar mass

Mass = 0.1875 mol ×78.07 g/mol

Mass = 14.64 g

The Mass of CaF₂ is 14.64 g. Molarity is the ratio of number of moles over the volume of solution.

Given:

Volume of solution = 1.25 L

Molarity of Solution = 0.15 M

To find:

Mass of CaF₂ = ?

Molarity is used to describe the concentration of solution. It is given by number of moles divided by volume of solution in litres.

Molarity = number of moles of solute / L of solution

We will calculate the number of moles of CaF₂ and then determine the mass by using number of moles.

0.15 M =  Number of moles of solute / 1.25 L

Number of moles of solute = 0.15 M *  1.25 L

Number of moles of solute = 0.1875 mol/L * L

Number of moles of solute = 0.1875 mol

Calculation of mass:

Mass = number of moles / molar mass

Mass = 0.1875 mol *78.07 g/mol

Mass = 14.64 g

Thus, the mass of CaF₂ is 14.64 grams.

Find more information about Molarity here:

brainly.com/question/14469428

Answer:

Explanation:

10 N right

Final answer:

The hydrologic or water cycle is the term for the movement of water between the ground, atmosphere, and bodies of water. It occurs through processes like evaporation, transpiration, condensation, precipitation, surface runoff, and groundwater flow, primarily driven by solar energy and gravity.

Explanation:

The movement of water between the ground, the atmosphere, and bodies of water is called the hydrologic cycle or water cycle. This cycle describes the continuous movement of water as it is evaporated from surfaces like rivers, lakes, and oceans into the atmosphere, forms clouds, precipitates as rain or snow, and returns to the surface. The cycle is driven by solar energy and gravity, moving water through various states: liquid, solid (ice), and vapor.

Water reaches the atmosphere through evaporation, transpiration (from plants), and sublimation (ice to water vapor). It returns as precipitation and may flow over the land as surface runoff or infiltrate into the ground to become groundwater, which slowly moves and can discharge into other bodies of water or return to the ocean.

Answer:

Metal, non-metal , and metaliod

Explanation:

Answer:

metal, nonmetal and metalloid

Explanation:

Answer:

4.98x10^-3 mole

Explanation:

According to Avogadro's hypothesis, 1 mole of any substance contains 6.02x10^23 atoms. This greatly implies that 1 mole of calcium will also contain 6.02x10^23 atoms.

Now, if 1 mole of calcium contains 6.02x10^23 atoms,

then Xmol of calcium will contain 3x10^21 atoms i.e

Xmol of calcium = 3x10^21/6.02x10^23

Xmol of calcium = 4.98x10^-3mol

Therefore, 4.98x10^-3 mole of calcium contains 3x10^21 atoms

3.00 × 10²¹ atoms of calcium are equivalent to 4.98 × 10⁻³ moles of calcium atoms.

To convert atoms to moles we need a conversion factor: Avogadro's number. According to Avogadro's number: there are 6.02 × 10²³ calcium atoms in 1 mole of calcium atoms. The number of moles corresponding to 3.00 × 10²¹ atoms of calcium are:

[tex]3.00 \times 10^{21} atoms \times \frac{1 mol}{6.02 \times 10^{23} atoms} = 4.98 \times 10^{-3} mol[/tex]

3.00 × 10²¹ atoms of calcium are equivalent to 4.98 × 10⁻³ moles of calcium atoms.

You can learn more about Avogadro's number here: https://brainly.com/question/13302703

Answer:

Metals

1) Sodium : It is used in the formation of table salt i. e. sodium chloride.

2) Copper : It is used in the wires of electricity due to better conduction.

3) Silver : It is used in wires and for making jewelry.

4) Aurum: It is used for making jewelry.

Non metals

1) Chlorine : It is used in the production of sodium chloride salt which is used in foods.

2) Flourine : It is used in making toothpaste.

3) Hydrogen : It is used in the formation of acids.

4) Oxygen : It is widely used in the production of steel and plastic.

Answer:

7

Explanation:

Answer:

Bromine has 7 valence electrons.

Explanation:

Bromine is in group 7 or 17, so it has 7 valence electrons use the Lewis structure for more help.

Answer:

Coal is layered because it is a type of sedimentary rock

Explanation:

Answer: P=1.63atm

Explanation:

Stp means standard temperature and pressure

Standard temperature =273k

Standard pressure =1atm

Using the formula

P1V1/T1=P2V2/T2

P1= 1atm

V1=5.23L

T1=273k

P2=?

V2=3.45L

T2=293k

Substitute the values

1×5.23/273=p2×3.45/293

Cross multiply

293×1×5.23=p2×3.45×273

1532.39=941.85p2

P2=1532.39/941.85

P2=1.627

P2=1.63atm

Answer:

It's C.

Explanation:

Firstly, the burning of carbon produces C02, a greenhouse gas. As nuclear fission does not produce carbon dioxide, it is not A. The decay of radioactive isotopes is not fission, or spliting into 2 parts.

As fission means to split, it is C.

Answer:

20.179

Explanation:

The answer is 20.179 because the element you are talking about is the element  Neon, which has the atomic mass of 20.179.