Which of the following statements about elements and atoms is true?

Answers

Answer 1

Answer:

the first one

Explanation:


Related Questions

can anyone try my questions, please will give points​

Answers

Answer:

um..... okay I'll give it a shot

is it an animal of plant cell?

Answers

Answer:

Structurally, plant and animal cells are very similar because they are both Eukaryotic cells. They both contain membrane-bound organelles such as the nucleus, mitochondria, endoplasmic reticulum, golgi apparatus, Iysosomes and peroxisomes. Plant cells can be larger than animal cells.

Explanation:

I majored in Chemistry

In order to follow the octet rule, how many valence electrons do most elements
want?
a. 2
b. 4
c. 6
d. 8

Answers

Answer: D (8)

Explanation:

Answer:

d. 8

Explanation:

The octet rule refers to the tendency of atoms to prefer to have eight electrons in the valence shell. When atoms have fewer than eight electrons, they tend to react and form more stable compounds.

How many liters of ammonia are formed with 49.8 g of nitrogen gas reacting with 10.7 g of hydrogen gas at S.T.P.?

Answers

the reaction is as follows:

N2+3H2---->2NH3

the number of moles of N2 is 49.8g/14gmol^-1=3.56mol

the number of moles of H2 is 10.7g/2gmol^-1=5.35mol

here, since the ratio of N2/H2 is 1/3, we can see that H2 is the limiting reagent. therefore, the reaction proceeds as follows:

N2 + 3H2 ---------------> 2NH3
5.36mol (2/3)(5.36mol)=3.57mol

therefore, the number of moles of ammonia formed is 3.57mol. at STP, P=1atm, T=273K.
Therefore, V(NH3)=(3.57)(22.38)=79.822 L


With your class, look up the element names for each symbol in the word "BOOK" and list the element names.

Answers

Explanation:

The word BOOK; is made up of 4 letters and each actually represents the symbol of an element.

An element is a distinct substance that cannot be split-up into simpler substances.

  B    -   Boron

  O    - Oxygen

  O   - Oxygen

  K   - Potassium

We can see that the word BOOK shows us elements boron, oxygen, oxygen and potassium.

8. Consider the element Scandium, atomic # 21.

(a) If the electronic configuration of the element were constructed "from scratch", into which

orbital (and into which shell) would the final electron be placed? (1)

(b) When scandium forms an ion with a charge of +1, from which orbital (and from which

shell) would the electron be removed? (1)

Answers

Explanation:

Scandium has atomic number of 21. This means that in it's neutral state its going to have 21 electrons.

a) The full electronic configuration is given as;

1s2 2s2 2p6 3s2 3p6 3d1 4s2

The final electron is placed in the d orbital. The shell is 3d

(b) When scandium has a charge if +1, it has lost an electron. The total number of electrons would now be 21-1 = 20

The electronic configuration would be given as;

1s2 2s2 2p6 3s2 3p6 4s2

The electron in the 3d orbital would be removed.

4 Describe What effect does observing a
substance's physical properties have on the
substance?

Answers

Answer:

From observing a substance's physical properties it has no effect on the substance because you are just observing it and not changing it.

Sodium will do an ionic bond with

Answers

Answer:

Chorine

Explanation:

It's a classic, sodium chloride, table salt, which is an ionic bond.

PLS GIVE BRAINLIEST

Which of the following values displays the pH of a base?
Question 19 options:

2

7

9

Answers

Answer:

9 is your answer

Explanation:

coz anything above 7.0 is Base on PH paper !

Hope you got it.

What type of radioactive decay is shown? 82 Br → 82 Kr + te 35 36 Alpha O Beta O Gamma?​

Answers

Answer:

In 1889, Ernest Rutherford recognized and named two modes of radioactive decay, showing the occurrence of both processes in a decaying sample of natural uranium and its daughters. Rutherford named these types of radiation based on their penetrating power: heavier alpha and lighter beta radiation. Gamma rays, a third type of radiation, were discovered by P. Villard in 1900 but weren't recognized as electromagnetic radiation until 1914. Since gamma radiation is only the discharge of a high-energy photon from an over-excited nucleus, it does not change the identity of the atom from which it originates and therefore will not be discussed in depth here.

Because nuclear reactions involve the breaking of very powerful intra nuclear bonds, massive amounts of energy can be released. At such high energy levels, the matter can be converted directly to energy according to Einstein's famous Mass-Energy relationship E = mc2. The sum of mass and energy are conserved in nuclear decay. The free energy of any spontaneous reaction must be negative according to thermodynamics (ΔG < 0), and ΔG is essentially equal to the energy change ΔE of nuclear reactions because ΔE is so massive.

Explanation:

Hope it helps

Which feature is most likely found at a divergent boundary?

Answers

Answer:

Most divergent plate boundaries are underwater and form submarine mountain ranges called oceanic spreading ridges. While the process of forming these mountain ranges is volcanic, volcanoes and earthquakes along oceanic spreading ridges are not as violent as they are at convergent plate boundaries.

Explanation:

Answer:

C-Fault block mountain

Explanation:

Tension occurs at divergent boundaries.  Tesnion is a type of stress that occurs when plates move apart.  Rocks stretch apart creating fault block mountains

please help I need to ace this test
When two atoms attach to each other by sharing electrons it is called a...

A: Covalent bond

B: Ionic bond

C: none of these - atoms can't bond to each other.

D: Nuclear bond

2nd question
Two hydrogen atoms bonded together form a compound
A: True
B: False

3rd question
Water is two hydrogen atoms bonded to an oxygen atom. This is an example of a compound

A: True

B: False
like I said I need help on this and I don't wanna fail

Answers

#1: A covalent bond

#2 False

#3True

what is the
difference between ice
and water vapour.


Answers

Answer:

Nothing. I guess ice vapor is a solid and water vapor is a liquid if nothing isn't an option, but that makes no sense.

Explanation:

Ice is a solid form and water vapour is the gas form

Which method of heat transfer is the person in the picture below most worried about?

Radiation

Conduction

Convection

Answers

Answer:

Radiation ...........

Hey There!_____________________________________Answer:

[tex]\huge\boxed{Conduction}[/tex]

_____________________________________Conduction:

Conduction is the transfer of heat when two things come in contact with each other. The energy transfer is from hotter body to the colder body.

                                x---------------------------------------------x

Fire Walking:

There is a trick behind fire-walking. When the coal burns, after sometime there is a layer of ash on the surface of the coal which blocks the radiation. So the transfer of heat is not possible from radiation. Conduction is the only way possible. The person's feet and coal both are poor conductor of heat so if we walk quickly i.e. there is minimal time of contact with the coal, it will just feel a little warm. As the person start walking on the coal, It has to do it quickly, that way Person will feel its sole warming up but it is not that hot because of the layer of ash and poor conductance, after few steps the ash also sticks on to the sole of the person which makes kind of double layers of ash. So the only way for heat transfer is CONDUCTION.

_____________________________________Best Regards,'Borz'

What is radioisotope?

Answers

Answer:

An unstable form of a chemical element that releases radiation as it breaks down and becomes more stable. Radioisotopes may occur in nature or be made in a laboratory. In medicine, they are used in imaging tests and in treatment.

Hope I could help!

Answer:

(RAY-dee-oh-I-suh-tope) An unstable form of a chemical element that releases radiation as it breaks down and becomes more stable. Radioisotopes may occur in nature or be made in a laboratory. In medicine, they are used in imaging tests and in treatment. Also called radionuclide.

Explanation:

Limestone formations in caves is considered what kind of weathering?

hydraulic

mechanical

biological

chemical

Answers

The answer is Chemical

Chemical weathering involves the decomposition of rocks due to chemical reactions between minerals such as calcite with water and gases in the atmosphere (e.g. carbon dioxide and sulphur dioxide). The solution of soluble minerals is particularly important in limestone landscapes.

Answer:

chemical

Explanation:

The metal element cesium has one electron in its outer orbit. Will cesium atoms form positively charged or negatively charged ions? Predict their charge.​

Answers

Answer:

Caesium atoms will form positively charged ions.

Explanation:

Due to them having one electron in their outer orbit, it is very likely that they will give that electron away to form an octet and become stable. Hence, since they lose an electron, they lose a negative charge, and in comparison to their former non-ion self, they have gained a positive charge.

Hence, they will form positively charged ions.

Hope this helped!

Balance the equation Mg+CO2 - - - - - -) MgO+c ​

Answers

Answer:

2Mg (s) + CO₂ (g) → 2MgO (s) + C (s)

General Formulas and Concepts:

Chemistry - Reactions

Reaction PredictionBalancing RxN's

Explanation:

Step 1: Define RxN

Mg (s) + CO₂ (g) → MgO (s) + C (s)

Step 2: Balance RxN

2Mg (s) + CO₂ (g) → 2MgO (s) + C (s)

We need to balance the number of O's on both sidesIf we balance the O's, we will also need to balance the Mg's

What determines whether something is a solid, a liquid or a gas?

Answers

Also, how fast the molecules are moving within the state of matter and how spread out they are.

why carbon is a basic thing to classify as organic and inorganic compounds?​

Answers

Answer:

To answer, all living organisms contain carbon-based compounds, which classifies them organic.

Simply, carbon dioxide, is an example of an inorganic compound since it does not contain both carbon and hydrogen. Alternatively, one molecule of carbon dioxide contains one atom of carbon and two atoms of oxygen.

Which models of the atom does the experimental evidence from Bohr's hydrogen experiment support? Explain why these models are compatible with the experimental results.

The models are Daltons, Thompsons, and Rutherfords

Answers

Answer:

Rutherfords

Explanation:

The model of the atom supported by Bohr's hydrogen experiment is the Rutherford's model of the atom.

Rutherford through his experiment on gold foil suggested the atomic model of the atom. The model posits that an atom has a small positively charged center(nucleus) where nearly all the mass is concentrated.

Surrounding the nucleus is the large space containing electrons. In the Bohr's model of the atom, he suggested that the extranuclear space of the atom is made up of electrons in specific spherical orbits around the nucleus.

How does the convection current drive, make the plates move?

Answers

Answer:

Geologists have hypothesized that the movement of tectonic plates is related to convection currents in the earth's mantle. ... Tremendous heat and pressure within the earth cause the hot magma to flow in convection currents. These currents cause the movement of the tectonic plates that make up the earth's crust.

Explanation:

Answer:

Geologists have hypothesized that the movement of tectonic plates is related to convection currents in the earth's mantle. ... Tremendous heat and pressure within the earth cause the hot magma to flow in convection currents. These currents cause the movement of the tectonic plates that make up the earth's crust.

Explanation:

Write the electron configuration for the electrons identified by the following quantum numbers:

a) 2, 1, 0, -½
b) 4, 2, 0, -½
c) 5, 3, 2, -½

Thanks!

Answers

Answer:

see the answer at the pic

The electron configuration for the electrons as listed are:

a) 1s² 2s² 2p⁵ = 9X

b) 1s² 2s² 2p⁶ 3s²  3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d⁸ = 46 X

c) 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p⁶ 7s² 5f¹⁴

Using the quantum numbers of the identified electrons to derive the electron configuration ( the representation of the distribution of electrons in the orbit of  an atom ) electron configuration of electrons can be calculated using the formula :2n².

where n = orbit number and the various energy levels are represented as 1,2,3,4... while shells of the an atom is written as K,L,M,N

hence the electron configuration of the electrons identified by the quantum numbers are as written above.

Learn more : https://brainly.com/question/20974986

the number of molecules in 7g nitrogen​

Answers

Answer:

the number of molecules in 7g nitrogen

Ans) 7 gram of Nitrogen contains 1.5×10^23 molecules =1.5e+23

What does the chemical formula CaCl2 show about the compound it represents?

A.It is made up of one element.
B.It is made up of two elements.
C.It is made up of three elements.
D. It is made up of four elements.

Help asap please

Answers

Answer:

b

Explanation:

Answer : B

Explanation :
Calcium and chlorine

PLEASE HELP I'LL MARK BRAINLIEST
Describe, on the molecular level, why my glasses get fogged up when I wear my face mask (so dang annoying). Be sure to use these terms: -decreased kinetic energy -surface -attraction

Answers

Answer:

When you are in a cool place and exhale into your mask, the mask blocks and re-directs some of your breath up toward the top edge of the mask and under your glasses. ... When the warm breath hits the cool lens, the water in the breath condenses causing your lenses to fog up.

Which element has a greater ionization energy, rubidium or iodine?

Answers

Answer: Iodine I think.

Explanation:

Use the information in the table to describe the temperature-vs.-time diagrams.

The diagram for gallium will have flat, horizontal lines
°C.
The diagram for methane will have a

line representing the

between -183°C and -162°C.
For gold, the boiling point corresponds to the y-value at
°C of the

For nitrogen, the line at -210°C will be
, which represents the

Answers

Answer:

At 30 and 2,204

diagonal

liquid phase

2856

top horizontal line

flat

the change from a solid to a liquid

Explanation:

1. What was the first recorded element to be discovered?

Answers

Answer:

Phosphorous

Explanation:

Although elements such as gold, silver, tin, copper, lead and mercury have been known since antiquity, the first scientific discovery of an element occurred in 1649 when Hennig Brand discovered phosphorous.

What is the relationship between the number of energy levels that an electron falls and the energy of the photon that is emitted when it falls?​

Answers

Answer:

Hope this helps! :)

Explanation:

Light is absorbed when an electron jumps to a higher energy orbit and emitted when an electron falls into a lower energy orbit. The energy of the light emitted or absorbed is exactly equal to the difference between the energies of the orbits.

The energy of the electron drops when it changes levels, and the atom releases photons. The emission of the photon occurs as the electron transitions from a higher to a lower energy state.

What is a photon ?

The electromagnetic force is carried by a photon, a basic particle that is a quantum of the electromagnetic field and includes electromagnetic radiation like light and radio waves. Since photons have no mass, they constantly travel in a vacuum at the speed of light.

When a photon of the appropriate wavelength collides with an atom, it vanishes and transfers all of its energy to the electron, which causes it to jump to a higher energy level.

The energy differential between two energy levels determines the amount of energy that is released during a certain transition.

Thus, The energy of the photon is precisely the energy that is lost when an electron moves to a level with less energy.

To learn more about photon, follow the link;

https://brainly.com/question/28134171

#SPJ2

Other Questions
(TRUE OR FALSE)As discoveries were made that couldn't be explained by spontaneous generations, scientist came up with an updated version of the spontaneous generation model?PLZ HELP WILL BRAINLIESTIF U DONT KNOW THE ANSWER DONT U DARE What were the achievements of the African empires, kingdoms, and cities before the arrival of the Europeans? Explain and evaluate these achievements. what political party did vicente fox oppose and when did it regain power You're a criminal mastermind who has broken into a gun manufacturing plant and wants to interfere with gun production in such a way thatthe guns produced in the factory won't be traceable. What are you looking to sabotage?A laser cutting device The element with 5 electrons in its 3d sublevel is...? All of the following are true of the Industrial Revolution EXCEPT *A)Technological advancements such as steam power and machine tools helped make the Industrial Revolution possibleB)The Industrial Revolution marked the transition from manual labor and draft animals to mechanizationC)One of the first industries transformed by the Industrial Revolution was the textile industryD)Industrialization happened nearly simultaneously in most areas of the world in the 18th centuryPlease hurry.... pls ayuda es para hoy mismo y es un examen Adrian gets a loan for $500 to go on a trip. He borrows the money at 5% interest for 1 year. Find the interest Adrian will pay on the loan. Read the dialogue and select the option that has the vocabulary needed to complete the sentences.Hola. Mi nombre es Rosario. Yo 1. ________ de Panam y 2. ________ baja. T, Matilda, 3. ________ divertida.Cmo 4. ________ tu amigo Pablo?A. 1. soy 2. es 3. soy 4. eresB. 1. eres 2. es 3. es 4. soyC. 1. soy 2. soy 3. eres 4. esD. 1. eres 2. soy 3. es 4. eres write the equation for this line INVENTORY FORM OF TOOLS AND EQUIPMENT_QUANTITY _UNIT_DESCRIPTION _CONDITION _REMARKS1.2.3.4.5.6.7.8.9.10.11.12.13.14.15.16.17.18.19.20. New inventions enabled women to in a wider variety of fields. Business offices changed in response to the invention of the . Women were thought to be better suited than men to perform this kind of office work and were hired in large numbers and paid than their male counterparts. In addition, inventions such as the created new jobs for women, but unlike positions in business offices, these jobs forced women to work in as a result of the technological innovation. Both these technologies helped the economy by increasing the of labor and by the labor market. In medieval feudalism, vassals gave their allegiance to a __________ in exchange for land._______________________________________________________A) kingB) lordC) peasantD) serf _______________________________________________________Please select the best answer from the choices providedA)B)C)D)_______________________________________________________ Why did Johann Gutenberg not become wealthy from his invention? please help and thanks Can organisms plan and willingly change theirmutations in their genes? Why or why not.simple answer 1 sentence please ? Question Drag each label to the correct excerpt from the poem. Identify which sound type each line contains. Excerpt 1: The sky was very dark; it was time to leave the park. Excerpt 2: Around high hills and over treacherous trails we kept marching forward be it night or day. Excerpt 3: The sky was very dark, but it was fun to go-kart. Excerpt 4: The tool in the hands of the fool nothing more than a stick. tiles: alliteration. slant rhyme. internal rhyme. end rhyme. why did tommy douglas want medicare to be apart of canada List the 5 ethnic islands in Wisconsin Solve for the value of p.