what is the element that is in f block and period 6 that is a rare earth metal

Answer:

1. A mathematical equation that predicts how a physical phenomenon will behave - Scientific law

2. A predicted experimental outcome based on prior knowledge and experience - Hypothesis

3. The variable that is changed on purpose by the scientist - Independent variable

4. The variables that must be kept constant so as not to bias or influence the results - Control variable

5. Data that is descriptive rather than numerical -Qualitative data

6. Data that is numerical - Quantitative data

7. A well tested explanation for why a physical phenomenon occurs - Scientific theory

Explanation:

In the method of science in understanding and explaining phenomena in the universe, observations are made, explanations are put forward, experimented and tested, before conclusions are made. Explanations of some common terms in the scientific process is given below:

1. A scientific law is a mathematical equation that predicts how a physical phenomenon will behave.

2. A hypothesis is a predicted experimental outcome based on prior knowledge and experience.

3. A independent variable is the variable that is changed on purpose by the scientist.

4. A control variable is the variable that must be kept constant so as not to bias or influence the results.

5. Qualitative data is data that is descriptive rather than numerical.

6. Quantitative data is data that is numerical

7. A scientific theory is a well tested explanation for why a physical phenomenon occurs.

Answer:

maybe greece

Explanation:

by henry cavendish in 1766

Answer:

What type of math are you taking.:)

Answer:

CaO

Explanation:

becoz

Ca O

2 2

you must crossing over the eqn

and get CaO

Answer:

El Niño refers to the above-average sea-surface temperatures that periodically develop across the east-central equatorial Pacific. It represents the warm phase of the ENSO cycle. La Niña refers to the periodic cooling of sea-surface temperatures across the east-central equatorial Pacific.

Answer:

Alpha particles, Beta particles, Gamma rays

Alpha Is the least harmful

Beta is second most harmful

Gamma is most dangerous

Explanation:

Answer: The rabbit population reached carrying capacity during the fourth year of the 10 years we set. Introduction: Population densityis the number of individuals in a population per unit of area. Some limiting factors only affect a population when its density reaches a certain level.

Explanation:

Answer:

Answer

Change in temperature

It is an example of an endothermic reaction. It is absorbing heat.

Answer:

132g/mol

Explanation:

Given compound:

   C₆H₁₂O₆

Molecular mass of the compound.

 This is the sum of the atomic masses of the given elements in the compound;

  C = 12

  H  = 12

  O = 6

Molecular mass = 6(12) + 12(1) + 6(16) = 180g/mol

Answer:

a: chemical change because the change cannot be reversed.

b: physical change because the action can be reversed.

c: chemical change.

d:chemical change.

any change that cannot be reversed is a chemical change and any change that can be reversed is a physical change.

Answer:

It would be a physical change, because the atoms are rerranging to form new molecules!

Explanation:

Answer:

Kinetic energy and potential energy

Explanation:

kinetic energy is when the energy is active and potential energy is when it is about to be active

Explanation:

Sodium sulfate

   Na₂SO₄

 The sulfate ion is SO₄²⁻

Sodium sulfite

    Na₂SO₃

 The sulfite ion is SO₃⁻

Sodium sulfide

   Na₂S

 The sulfide ion is S²⁻

Sodium phosphate

 Na₂PO₄

 Phosphate ion is PO₄²⁻

Sodium phosphite

Na₃PO₃

  The phosphite is PO₃³⁻

Sodium phosphide

 Na₃P

  The phosphide ion is P³⁻

Answer:

D=Wavelength A=Amplitude C=Crest F=At rest point

Explanation:

Forgive me if I am wrong!

Answer:

(It doesn't need to be m/s, but it's the most common unit. It's basically any unit of length divided by any unit of time)

hope this helps and good luck

Answer/Explanation:

Speed is a force and is solved by using acceleration.

You can use the problem to solve for force:

F= MA or Force equals mass times acceleration.

Answer:

Radioactive elements

Stable

Explanation:

Radioactive elements that have a longer half-life are more stable than those that a shorter half-life.

Half-life is the time taken for half of a radioactive element to decay by half of its original composition.

Now, if a substance have a long half-life, it is more stable and takes time to break down. For atoms with a short life, they are highly unstable and breaks down readily and easily.

Answer:

in details

Explanation:

what are the properties of iconic compounds?

Ionic compounds exist in the form of ionic groupings in certain forms called (crystalline forms), and we find in these shapes an organized crystal arrangement of ions so that every ion with a specific charge is attracted to a group of ions with the opposite charge, meaning that one ion is bound by several ionic bonds. At the same time, this explains the presence of ionic compounds usually in the solid state (high density). This situation also explains the high melting and boiling points of these compounds.

One of the most important characteristics of ionic compounds is their inability to conduct electrical conductivity in the solid state due to the ions binding and their inability to move while they become conductive of electricity when they are melted or dissolved in water (ions are free to move in the melt and in the aqueous solution).

And among its most important characteristics:

1- It dissolves in water and does not dissolve with benzene, for example (salt) because water is a polar solvent that can separate ions from each other.

2- It has a high melting point due to the force of electrostatic attraction between the positive and negative ions.

3- Its state is solid under normal conditions, due to the force of the electrostatic attraction between the positive and negative ions.

4- Solid ionic compounds do not conduct electricity, but their solutions with water conduct electricity, because when the compound is solid, the ions are connected to each other, but when the compound is a solution, the ions are free to move and conduct the electromagnetic current.

what are the properties of covalent compounds?

In covalent compounds (unlike ionic compounds), we can talk about independent molecules, as covalent compounds are composed of independent molecules linked together by different bonds (van derval, hydrogen) of varying strength. So there are covalent compounds in all three cases according to the strength of these bonds. There are covalent compounds in a gaseous state (weak bonds between molecules), covalent compounds in a liquid state, and also there are covalent compounds in a solid state (strong bonds between molecules). The same is true for melting and boiling points, so covalent compounds Their boiling and melting points vary according to the quality and strength of the bonds between the molecules.  

As for the electrical conductivity, in the pure state, the covalent compounds are mostly non-conductive because they are not originally charged or because they are electrically neutral in the presence of charges, but the charged ones may have what is known as the electric torque and will come.

Likewise, in their smelters, the molten solid covalent compound (such as molten sugar) is not conductive of electricity. As for the solution, it may be non-conductive as in the case of a sugar solution or be conductive as is the case in a solution of hydrogen chloride (hydrochloric acid) and the reason for conducting or not in the solution is due to The covalent compound ionization (conversion into separate ions by the action of a solvent) or its de-ionization.

Sugar does not ionize when dissolved in water. Rather, its molecules only separate from each other, while hydrogen chloride does ionize to the hydrogen ion and the chlorine ion.

which type of compound is sugar?

The chemical or molecular formula for sucrose is C 12 H 22 O 11, which means that each sugar molecule contains 12 carbon atoms, 22 hydrogen atoms, and 11 oxygen atoms. A type of sugar called sucrose is also known as sucrose. It is a sucrase made in many different plants.

The properties of the compounds are the following:

a. The properties of the ionic compounds are they are hard, form crystals, have high melting and boiling point, good insulators.

b. The properties of the covalent compound are they are soft, do not form the crystal, have low melting and boiling point, bad insulators.

c. Sugar is a covalent compound.

Covalent compounds are attracted by covalent bonds. They make bonds by sharing one or more pairs of valence electrons.

These compounds are ions or charged particles. They make bonds when an atom or more atoms lose or gain electrons.

Thus, the properties are a. The properties of the ionic compounds are they are hard, form crystals, have high melting and boiling point, good insulators.

b. The properties of the covalent compound are they are soft, do not form the crystal, have low melting and boiling point, bad insulators.

c. Sugar is a covalent compound.

Learn more about covalent compounds

https://brainly.com/question/14752836

Answer:

b. Their shells

Explanation:

The electronic shell of atoms represents the energy levels in a particular atom.

To understand the way atoms absorb energy, we must know that the wavelength absorbed is commensurate with the energy of the atom. This available energy allows for specific amount of energy to be absorbed.

Therefore, the electronic shell in an atom determines the absorption wavelength of the atom.

Answer:

2

Explanation:

Answer:

A: ozone

Explanation:

Answer:

A: ozone

Explanation:

right on EDGE 2021

Answer:

1.181 × 10²⁴ molecules CO₂

General Formulas and Concepts:

Chemistry - Atomic Structure

Explanation:

Step 1: Define

86.34 g CO₂

Step 2: Identify Conversion

Avogadro's Number

Molar Mass of C - 12.01 g/mol

Molar Mass of O - 16.00 g/mol

Molar Mass of CO₂ - 12.01 + 2(16.00) = 44.01 g/mol

Step 3: Convert

[tex]86.34 \ g \ CO_2(\frac{1 \ mol \ CO_2}{44.01 \ g \ CO_2} )(\frac{6.022 \cdot 10^{23} \ molecules \ CO_2}{1 \ mol \ CO_2} )[/tex] = 1.18141 × 10²⁴ molecules CO₂

Step 4: Check

We are given 4 sig figs. Follow sig fig rules and round.

1.18141 × 10²⁴ molecules CO₂ ≈ 1.181 × 10²⁴ molecules CO₂

The percent yield of indigo : 79.6%

Percent yield is the comparison of the amount of product obtained from a reaction with the amount you calculated

General formula:

Percent yield = (Actual yield / theoretical yield )x 100%

An actual yield is the amount of product actually produced by the reaction. A theoretical yield is the amount of product that you calculate from the reaction equation according to the product and reactant coefficients

Reaction

2C₁₀H₁₁NO₄ + 2H₂O → C₁₆H₁₀N₂O₂ + 2C₂H₄O₂ + 4H₂O

Actual yield = 1.87 g

Theoretical yield = 2.35 g

The percent yield of indigo :

[tex]\tt \%yield=\dfrac{actual}{theoretical}\times 100\%\\\\\%yield=\dfrac{1.87}{2.35}\times 100\%=\boxed{\bold{79.6\%}}[/tex]

Answer:

What??? I don't understand.

Explanation:

Answer:

They must be dissolving.

Explanation:

Acid molecules must cling to remaining food molecules and slowly dissolve them.

Answer:

The energy of photon is 33.28×10⁻¹⁴  J

Explanation:

Given data:

Frequency of photon = 5.02×10²⁰ Hz

Energy of photon = ?

Solution:

E = h.f

h = planc'ks constant = 6.63×10⁻³⁴ Js

by putting values,

E =  6.63×10⁻³⁴ Js × 5.02×10²⁰ Hz

        Hz = s⁻¹

E = 33.28×10⁻¹⁴  J

The energy of photon is 33.28×10⁻¹⁴  J.

Answer:

Explanation:

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

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

From the question we have

[tex]density = \frac{374}{2.2 \times {10}^{3} } = \frac{17}{100} \\ [/tex]

We have the final answer as

Hope this helps you

Answer:

In the human body, potential energy is stored in the bonds between atoms and molecules. Chemical energy is the form of potential energy in which energy is stored in chemical bonds. When those bonds are formed, chemical energy is invested, and when they break, chemical energy is released. Notice that chemical energy, like all energy, is neither created nor destroyed; rather, it is converted from one form to another. When you eat an energy bar before heading out the door for a hike, the honey, nuts, and other foods the bar contains are broken down and rearranged by your body into molecules that your muscle cells convert to kinetic energy.

Explanation: