Is iodine a atom,a molecule,an ion or a formule unit?

Answers

Answer 1

Answer:

It's an atom

Explanation:

It can't be a molecule since it's only one element, the ion would've been Iodide (I-), and it's not a formula


Related Questions

In the molecule 4H2O2 the number of hydrogen atoms is what

Answers

There are 8 hydrogen atoms.

4H2 actually means
[tex]4H_{2}[/tex]

Answer:

Scientists

Explanation:

Scientists because they are the one who makes hypothesis.

urgent plz help thanks!
Which statement best describes a compound formed by an ionic bond?

A) negatively charged
B) neutral
C) contains multiple charges
D) positively charged​

Answers

Answer:

B. Neutral

Explanation:

When there is a ionic bond,  one element steals or takes away an electron from the other element.

An example is NaCl

In this compound, Chlorine atom steals an extra electron from Sodium to fill its outer shell. So, this is a Ionic bond. Since, the Sodium compound gives away an atom, it is positively charged. Since, Chlorine steals an atom, it is negatively charged. Opposite charges attract, so they become a compound.

When positive and negative mix, it becomes neutral.

A student is reading the volume from a standard 50-mL buret identical to what you used in the lab. The bottom of the meniscus is exactly on the 20-mL line. What should she record as the correct volume

Answers

Answer:

20 mL

Explanation:

The student should record 20 mL as the correct volume.

The curved surface of a liquid that is usually observed in a buret is referred to as the meniscus. This meniscus is created as a result of the surface tension of the liquid against the walls of the buret. Hence, in order to avoid errors due to parallax, the bottom of the meniscus should be read and not the top.

Therefore, the correct volume that the student should record is 20 mL.

Explain why chlorine is a gas while iodine is a solid yet both are halogens. Select one: a. Both iodine and chlorine differ in strength of metallic bonds b. Chlorine has strong inter molecular forces than iodine c. Iodine molecules are large with strong inter molecular forces than chlorine

Answers

Answer:

Chlorine has strong inter molecular forces than iodine

Explanation:

Answer:

Chlorine has strong inter molecular forces than iodine

Explanation:

I2 is a solid while Cl2 is a gas because Iodine molecules are larger and therefore experience stronger intermolecular forces.

HOPE IT HELPS :)

PLEASE MARK IT THE BRAINLIEST!

Which scientist developed a new model of planetary motion?

Answers

Answer: Johannes Kepler

Answer:

i believe the answer us kepler

Explanation:

Consider two bulbs seperated by a valce. Both bulbs are amintained at the same temperature. Assume that when the valve between the two bulbs is closed, the gases are sealed in their respective bulbs. When the valve is closed, the following data apply:

Bulb A Bulb B
Gas Ne CO
V 2.50L 2.00L
P 1.09 atm 0.73 atm


Assuming no temperature change, determine the final pressure inside the system after the valve connecting the two bulbs is opened. Ignore the volume of the tube connecting the two bulbs.

Answers

Answer:

The  pressure is [tex]P_f = 0.93 \ atm[/tex]

Explanation:

From the question we are told that

   The  volume of  Ne  is  [tex]V_N = 2.50 \ L[/tex]

    The volume  of  CO is  [tex]V_C = 2.00 \ L[/tex]

    The  pressure of  [tex]Ne[/tex] is  [tex]P_N = 1.09 \ atm[/tex]

      The  pressure of  CO is [tex]P_C = 0.773 \ atm[/tex]

The  number of  moles of  Ne present is evaluated using the ideal gas equation as

      [tex]n_N = \frac{P_N * V_N}{R T}[/tex]

=>   [tex]n_N = \frac{1.09 * 2.50 }{R T} = \frac{2.725}{RT}[/tex]

The  number of  moles of  CO present is evaluated using the ideal gas equation as

      [tex]n_N = \frac{P_C * V_C}{R T}[/tex]

=>   [tex]n_N = \frac{0.73 * 2.00 }{R T} = \frac{1.46}{RT}[/tex]

The  total number of moles of gas present is evaluated as

        [tex]n_T = n_N + n_C[/tex]

        [tex]n_T = \frac{2.725}{RT} + \frac{1.46}{RT}[/tex]

      [tex]n_T = \frac{4.185}{RT}[/tex]

The  total volume of gas present when valve is opened is  mathematically represented as

                [tex]V_T = V_N + V_C[/tex]

    =>        [tex]V_T = 2.50 + 2.00 = 4.50 \ L[/tex]

So

  From the ideal gas equation the final pressure inside the system  is mathematically represented as

         [tex]P_f = \frac{n_T * RT }{ V_T}[/tex]

=>      [tex]P_f = \frac{[\frac{4.185}{RT} ] * RT }{ 4.50}[/tex]

=>       [tex]P_f = 0.93 \ atm[/tex]

     

2. Bottled Italian salad dressing is an example of *
O a suspension
a colloid
a solution
O a homogeneous mixture

Answers

a suspension, which is a heterogeneous mixture. it has different parts.

PLEASE PLEASE HELP!!!! What is the mass of a sample material that has a volume of 72.2cm³ and a density of 7.7g/cm³?

Answers

Answer:

The answer is

555.94g

Explanation:

To find the mass of a substance given it's density and volume we use the formula

[tex]Density \: = \frac{mass}{volume} [/tex]

Making mass the subject we have

mass = Density × volume

From the question

Density = 7.7 g/cm³

Volume = 72.2 cm³

Substitute the values into the above formula

That's

mass = 7.7 g/cm³ × 72.2 cm³

We have the final answer as

mass = 555.94g

Hope this helps you

change the following word equations into balanced equations

a) Hydrogen + Chlorine → Hydrogen chloride.

b)Hydrogen + Nitrogen→ Ammonia

c)Aluminium + sulphuric acid → Aluminium sulphate + Hydrogen

d)Iron (3) + oxygen → iron oxide

e)Copper + sulphuric acid → Copper sulphate + water + sulphur dioxide.

Answers

Answer:

Q

Explanation:

what is the relative formula mass of phosphate (PO4)? (To the nearest tenth) A. 187.9 grams B. 46.9 grams C. 23.0 grams D. 94.9 grams

Answers

Answer:

[tex]\huge\boxed{94.9\ grams}[/tex]

Explanation:

Relative formula mass of phosphate:

=> [tex]PO_{4}[/tex]  [Ignoring the charge on it]

Atomic mass of P = 31.0 grams, O = 15.9 grams

=>  30.97 + 4(15.9)

=> 30.97 + 63.9

=> 94.87

94.9 grams [To nearest tenth]

Answer:

[tex]\huge \boxed{\mathrm{D. \ 94.9 \ grams}}[/tex]

Explanation:

Phosphate chemical formula is given as,

[tex]\sf PO_4[/tex]

There is one phosphorus atom and four oxygen atoms.

Atomic mass of Phosphorus [tex]\sf P[/tex] = 30.974 grams

Atomic mass of Oxygen [tex]\sf O[/tex] = 15.999 grams

[tex]\Rightarrow 30.974 + 4(15.999)[/tex]

[tex]\Rightarrow 30.974+ 63.996[/tex]

[tex]\Rightarrow 94.97[/tex]

The relative formula mass of phosphate [tex]\sf PO_4[/tex] is 94.9 grams.

Which of the following is an acid-base neutralization reaction? (1 point) Sn + 2HBr yields SnBr2 + H2 HCl + KOH yields KCl + H2O 2AlCl3 + 3Ca(OH)2 yields 2Al(OH)3 + 3CaCl2 2C2H6 +7O2 yields 4CO2 + 6H2O

Answers

Answer:

HCl + KOH ⇒ KCl + H₂O

Explanation:

Which of the following is an acid-base neutralization reaction?

Sn + 2HBr ⇒ SnBr₂ + H₂. NO. This is a single displacement reaction.

HCl + KOH ⇒ KCl + H₂O. YES. An acid reacts with a base to form salt and water.

2AlCl₃ + 3Ca(OH)₂ ⇒ 2Al(OH)₃ + 3CaCl₂. NO. This is a double dispacement reaction.

2C₂H₆ +7O₂ ⇒ 4CO₂ + 6H₂O. NO. This is a combustion reaction.

c. CaCl2 can be melted to produce calcium metal and give off chlorine gas. The equation for this
is CaCl2()→ Ca(s) + Cl2(g). If 277.45 g CaCl2 were melted, how many grams of Ca(s) would
be formed? (10 points)

HELP MEEEEE PLEASE

Answers

Answer:

Total gram of Ca = 99.26 g

Explanation:

Given:

Mass of CaCl₂ = 277.45 g

Find:

Mass of Ca

Computation:

Ca = 40 g/mol

Cl₂ = 2 (35.5) g/mol = 71 g/mol

Total CaCl₂ = 111 g/mol

Total gram of Ca = [40 / 111] 277.45 g

Total gram of Ca = 99.26 g

find the empirical formula of the compound containing 11.3% of carbon, 43.4 % of sodium 45.3 % of oxygen ​

Answers

Answer:

CNa203

Explanation:

thats is method in the picture send

A star is estimated to have a mass of 2.0 x 10 ^36kg. Assuming it to be a sphere of average radius of 7.0 x 10 ^5 km. Calculate the average density of the star in g/cm^3 and in lb/ft^3

Answers

Answer:

a) 1.392 x 10^6 g/cm^3

b) 8.69 x 10^7 lb/ft^3

Explanation:

mass of the star m =  2.0 x 10^36 kg

radius of the star (assumed to be spherical) r = 7.0 x 10^5 km = 7.0 x 10^8 m

The density of substance ρ = mass/volume

The volume of the star = volume of a sphere = [tex]\frac{4}{3}\pi r^{3}[/tex]

==> V = [tex]\frac{4}{3}*3.142*(7.0*10^8)^{3}[/tex] = 1.437 x 10^27 m^3

density of the star ρ = (2.0 x 10^36)/(1.437 x 10^27) = 1.392 x 10^9 kg/m^3

in g/cm^3 = (1.392 x 10^9)/1000 = 1.392 x 10^6 g/cm^3

in lb/ft^3 =  (1.392 x 10^9)/16.018 = 8.69 x 10^7 lb/ft^3

Explain why the first ionisation energy of helium is
larger than that of hydrogen.​

Answers

Answer

Explanation:

helium has a structure 1s² the electrons are removed from the same orbital as in case of hydrogen the electrons are closest to the nucleus the value of ionization energy of helium is much higher than hydrogen  because the nucleus now has 2 proton attracting  the electrons instead of 1 in case of hydrogen

what is the correct electron configuration for an element with five electrons in the third energy level

Answers

That would be phosphorus. It’s electron configuration is 1s^2 2s^2 2p^6 3s^2 3p^3

[tex]1s^2 2s^2 2p^6 3s^2 3p^3[/tex] is the correct electron configuration for an element with five electrons in the third energy level.

What are elements?

Elements are the simplest substances which cannot be broken down using chemical methods.

The shell nearest to the nucleus, 1n, can carry two electrons, while the next shell, 2n, can carry eight, and the third shell, 3n, can carry up to eighteen.

The third shell carries 18 electrons; 2 in a 3s orbital; 6 in three 3p orbitals; and 10 in five 3d orbitals. The fourth shell carries  32 electrons; 2 in a 4s orbital; 6 in three 4p orbitals; 10 in five 4d orbitals; and 14 in seven 4f orbitals.

The element would be phosphorus. Its electron configuration is [tex]1s^2 2s^2 2p^6 3s^2 3p^3[/tex]

Learn more about elements here:

brainly.com/question/1896898

#SPJ2

what’s the answer to this?

Answers

the mass weight of the rock is 6.8g

Tips for memorizing the first 20 elements of the periodic table?​

Answers

Answer:

hydrant flying with balloon, balloon has lithp letting air out, bee: really yum balloon

    =                           =                                 =                                   =

hydrogen              helium                     lithium                     beryllium

be bore on the balloon, balloon pops, hydrant drops and makes a car bomb

           =                                                                                                  =

    boron                                                                                              carbon

night row general gets hurt by car bomb nearby, that general gets off boat

        =                                

nitrogen

wearing oxygen mask, mask is full of fluride gel, then he got neon teeth

             =                                               =                                      =

         oxygen                                fluorine                                neon

(try making a story out of the elements, use your imagenation)

I will give u tips to learn whole periodic table

1. Break down the table into sections

2. Spread out the memorisation process

3. Learn the elements in a song

4. Make none sense words made from element symbols

5. Use colour to learn element groups

6. Use mnemonic device to help remember the order of elements

I am sure this will be helpful for uuu

Explanation:

Drag each tile to the correct image. Match each hydrocarbon class to its structure. carboxylic acid amine halocarbon alcohol

Answers

Answer:

1. Amine.

2. Alcohol.

3. Carboxylic Acid.

4. Halocarbon.

Explanation:

The correct answer according to the tile are Amine, Alcohol, Carboxylic acid, Halocarbon.

How can hydrocarbons be classified based on their structure?

Hydrocarbons can be classified as either aromatic or aliphatic compounds, depending on the presence of a benzene ring.

What is the most common classification of hydrocarbons?

Alkanes are hydrocarbons in which all of the bonds are single bonds. Alkenes are hydrocarbons that contain a carbon-carbon double bond.

Learn more about hydrocarbon here : brainly.com/question/490217

#SPJ2

Use the following steps to balance the redox reaction using half-reactions. Zn(s) + Fe3+ Zn2+ + Fe(s) (unbalanced) a. Write balanced oxidation and reduction half-reactions. Indicate which is the oxidation reaction and which is the reduction reaction. (6 points) b. Balance the charge in the two half-reactions by multiplying the half-reactions by the correct multiplication factors. (4 points) c. Add the equations and simplify to get the balanced equation.

Answers

Answer:

Explanation:

a )

Zn = Zn²⁺ + 2e   ( oxidation reaction )

Fe³⁺ + 3e = Fe( s ) ( reduction reaction )

b )

[ Zn = Zn²⁺ + 2e ] x 3

[ Fe³⁺ + 3e = Fe( s ) ] x 2

-------------------------------------------------------------------

3 Zn + 2 Fe³⁺ + 6e = 3 Zn²⁺ + 2 Fe ( s ) + 6e

3 Zn + 2 Fe³⁺  = 3 Zn²⁺ + 2 Fe ( s )

What is the complete ionic equation for this reaction?
2KOH(aq) + H2SO4(aq) → 2H20(1) + K2SO4(aq)
O A. 2K+ + OH + H2SO4 → OH + 2H+ + K2SO4
B. OH + 2H+ + 2H20()
C. 2KOH + H2SO4 → 2H20 + K2SO4
D. 2K+ + OH + 2H+ + SO42- → 2H20() + 2K+ + SO42-
SUBMIT

Answers

Answer:

The answer is "Option D".

Explanation:

The entire ionic equation for all the substances, which are ionic compounds but are available in an aquatic is represented in the form with ions in the full ionic equation.  

In the Net ionic equation, it doesn't have the particulate matter throughout the net ionic equations throughout the equations.  

In the Spectator ions, it doesn't participate in interactions mostly on reaction and the material hand. From both sides, the very same ions are present.  

The evenly balanced chemical formula is,

[tex]2KOH (aq)+ H_2SO_4(aq) \longrightarrow 2H_2O(l) + K_2SO_4[/tex]

It is the separate organic compound that full ion formula will match the choice D.

All carbon ato ms have atomic number 6 but some have mass number 12 and others have mass number 14.what is a) the same b) different about the structure of these two types of carbon atoms

Answers

Answer:

a) The similarities in their structure are;

1) The two isotopes have the same number of protons in their nucleus

2) The two isotopes have the same number of electrons in their orbit

3)The basic chemical properties of the two isotopes are the same

b) The differences in their structure are;

1) The number of neutrons in their nucleus are different

6 for carbon 12 and 8 for carbon 14

2) The structure of carbon 12 is stable while the structure of carbon 14 disintegrates

3) The isotopes have different densities, therefore, different packing

Explanation:

The atomic number is the number of protons in the nucleus of an atom

The mass number is the sum or total number of protons and neutrons in an atom

Given that the atomic number of all carbon atoms = 6

The number of protons in all carbon atoms = 6

Given that some of the carbon atoms have a mass number of 12 while others have a mass number 14, we have

Therefore, the number of neutrons in some of the carbon atoms = 12 - 6 = 6

The number of neutrons  in the remaining of carbon atoms = 14 - 6 =  8

Therefore the carbon atom has two isotopes including ¹²₆C and ¹⁴₆C.

A compound that has a sea of delocalized electrons has what type of bonding?

Answers

Answer:

Metallic Bonding

Explanation:

Metallic Bonding

In metallic bonds, the valence electrons from the s and p orbitals of the interacting metal atoms delocalize. That is to say, instead of orbiting their respective metal atoms, they form a “sea” of electrons that surrounds the positively charged atomic nuclei of the interacting metal ions.

Citrus fruits may taste sour because they are _____. acidic basic neutral too ripe

Answers

Answer:

A. acidic

Explanation:

Citrus fruits may taste sour because they are acidic. They have citric acid and ascorbic acids.

Was is meant by the term suprenatural? Does science deal with the supernatural?

A. The term supernatural literally means (within nature) Science deals with the supernatural because it works within nature, not above it

B. The term supernatural literally means (above nature) Science does not deal with the supernatural because it works within nature, not above it

C. The term supernatural literally means (within nature) Science does not deal with the supernatural because it works above nature, not within it

D. The term supernatural literally means (above nature) Science deals with the supernatural because it also works with nature, not within it

Answers

Answer:

it's option D

What happens when two objects when they are brought closer together The mass of both objects decrease The mass of both objects increase The gravitational force between them decreases The gravitational force between them increases

Answers

Answer:

The correct option is

The gravitational force between them increases

Explanation:

According to Newton's law of universal gravitation states that the force of attraction between two bodies is directly proportional to the product of the masses of the bodies and inversely proportional to the square of the distance of their centers from each other.

The formula for universal gravitation is given as follows;

[tex]F_{1} = F_{2} =G \times \dfrac{m_{1} \times m_{2}}{r^{2}}[/tex]

Where;

F₁, and F₂ = The gravitational forces of attraction on each mass

G = The gravitational constant

m₁ = The mass of one body

m₂ = The mass of the body

r = The distance between the centers of the two bodies

Therefore, the gravitational force of attraction on each object is inversely proportional to the as the distance between the centers of the two bodies

When the distance between the centers of the two bodies decreases, the two objects are brought closer together, the gravitational force of attraction between them increases.

Answer:

Gravitational force between two objects of masses m1/m2

Explanation:

is defined by Gm1xm2/r^2, where G is a universal constant, and r is the distance between the masses. This shows you why B is wrong; it would increase. Also, A is not a good choice, as shown. In the case of B, it would increase by say, 2/1 to 4/1 by doubling ones mass. In C's case the bottom would decrease on the fraction alot (square) if they were moved closer, thus the force would be greater.

Explanation:

in other words the  answer is The gravitational force between them increases

can you catch coronavirus from F.A.R.Ts?

Answers

Answer:

No

Explanation:

Droplets or aerosols. When an infected person coughs, sneezes, or talks, droplets or tiny particles called aerosols carry the virus into the air from their nose or mouth. Anyone who is within 6 feet of that person can breathe it into their lungs.

Airborne transmission. Research shows that the virus can live in the air for up to 3 hours. It can get into your lungs if someone who has it breathes out and you breathe that air in.

Surface transmission. Another way to catch the new coronavirus is when you touch surfaces that someone who has the virus has coughed or sneezed on. You may touch a countertop or doorknob that's contaminated and then touch your nose, mouth, or eyes. The virus can live on surfaces like plastic and stainless steel for 2 to 3 days. To stop it, clean and disinfect all counters, knobs, and other surfaces you and your family touch several times a day.

Fecal-oral. Studies also suggest that virus particles can be found in infected people's poop. But experts aren't sure whether the infection can spread through contact with an infected person's stool. If that person uses the bathroom and doesn't wash their hands, they could infect things and people that they touch.

Suppose you see an advertisement for a video game that claims you can actually fly around inside your home while you play it. What do your scientific literacy and critical thinking skills lead you to think about that claim?

Answers

Answer:

Scientific literacy and critical thinking skills will nullify the claims made in the advertisement.

Explanation:

The claims made in the advertisement contradict the scientific laws and the person who understands the scientific theories can easily understand that. Critical thinkers may derive rational insights from a collection of facts, and distinguish between relevant and less important reasons for problem-solving or decision making. Therefore on objectively evaluating scientific theories, we conclude to a rational decision, that is the claims are false.

Si se usa 450 gramos de carbonato de calcio para dicho proceso ¿Qué volumen de CO2 se obtendrá, si la presión es de 8 atm y la temperatura 200°C? R=0,082 atm.L/mol.K

Answers

Respuesta:

21.8 L

Explicación:

Paso 1: Escribir la reacción balanceada

CaCO₃ ⇒ CaO + CO₂

Paso 2: Convertir 450 g de CaCO₃ a moles

La masa molar de CaCO₃ es 100.09 g.

450 g × (1 mol/100.09 g) = 4.50 mol

Paso 3: Calcular los moles de CO₂ que se forman a partir de 4.50 moles de CaCO₃

La relación molar de CaCO₃ a CO₂ es 1:1. Los moles de CO₂ formados son 1/1 × 4.50 mol = 4.50 mol.

Paso 4: Convertir la temperatura a Kelvin

Usaremos la siguiente expresión.

K = °C + 273.15 = 200°C + 273.15 = 473 K

Paso 5: Calcular el volumen de CO₂

Usaremos la ecuación del gas ideal.

P × V = n × R × T

V = n × R × T / P

V = 4.50 mol × (0.082 atm.L/mol.K) × 473 K / 8 atm

V = 21.8 L

12g of carbon react with 32g of oxygen to produce 44g of CO2 .which chemical law do the data illustrate​

Answers

Answer:

Law of constant composition

Answer:

trtytytytytytyt

Explanation:

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