A chemical equation is balanced by changing or adding
a.
chemical symbols.
c.
numbers in front of molecules.
b.
subscripts after atoms.
d.
reactants in the product.

Answers

Answer 1
A chemical equation is balanced by changing or adding C. numbers in front of molecules, which are called coefficients. 
For example:
O2 + 2 H2 ---> 2 H2O (number 2 is added to both sides in order to balance the equation)
Answer 2

Answer:

a.

chemical symbols.

Explanation:


Related Questions

name two properties of many substances containing ionic bonds

Answers

Conduct electricity when dissociated in a water and are brittle solids at room temperature. They also have high melting and boiling points. 
The metallic elements tend to form cations and the non metals tend to from anions when ion compounds dissociate. 

Ionic compounds have high melting and boiling points due to strong ionic bonds and conduct electricity when dissolved in water or molten, as the ions are free to move.

Two properties of substances containing ionic bonds are:

High melting and boiling points: Substances with ionic bonds tend to have high melting and boiling points because the electrostatic forces of attraction between their ions are very strong. Ionic compounds, for instance, maintain a crystal lattice that requires a large amount of energy to break apart.Conductivity: When ionic compounds are in their solid state, they are poor conductors of electricity due to the fixed positions of ions within the crystal lattice that prevent free movement. However, once dissolved in water or molten, the resulting free ions allow the substance to conduct electricity effectively. This is because ions are then able to move freely and carry charges through the solution or molten liquid.

These properties arise from the strong electrostatic forces that hold the oppositely charged ions together, creating ionic compounds with characteristic behaviors when in different states.

Why does ln(1/2) = -ln(2) please explain mechanic to get to this solution ...?

Answers

The solution to the problem is as follows:


Remember that 1/2 = 2^(-1).
ln(1/2) = ln(2^(-1))
Using the law of logarithm: ln(b^a) = a ln b.
ln(1/2) = (-1)ln 2 = -ln 2.

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what is a fusion reaction

Answers

When two atoms of Hydrogen combine together, or fuse, they make an atom of Helium. 

Look around and write down two or three examples of matter and energy that you observe.

Answers

Everything is made of matter, so anything you see will do for the matter portion. If you have a water bottle sitting on a desk, that has potential energy, and if you have a dog thats running and such, it has kinetic energy. I hope this helps!

Examples of matter include a cup of coffee and the air we breathe, while energy is seen as sunlight shining through a window. Matter consists of substances that have mass and occupy space, and energy is the capacity to perform work or bring about change.

Examining the world around us, we can find numerous examples of matter and energy. For instance, a cup of coffee on your desk is an example of matter, containing energy in the form of heat.

Another example of matter would be the air you breathe, which is a mixture of gases like nitrogen, oxygen, and carbon dioxide. As for energy, sunlight streaming through a window illustrates energy in the form of light and heat.

These examples help us understand that matter is anything that has mass and takes up space, while energy is the capability to do work or cause change.

Matter can exist in different states, including solid, liquid, and gas. For example, ice is water in its solid state.

When absorbing energy, this ice can melt into liquid water, exemplifying a phase change that involves energy transfer. Alternatively, water vapor condensing into liquid showcases a phase change where energy is released.

To comprehend the complexities of these transitions and the role of energy, it is vital to explore the conservation of energy, which states that energy cannot be created or destroyed, only transformed from one form to another.

Investigations in this area could include lab experiments verifying the law of conservation of energy by observing phase changes and measuring the energy involved.

Why is KCl a better salt-bridge than NaCl?

Answers

KCl is a better salt-bridge than NaCl  because : 
Na+ is higher on the chart and has a larger reduction potential, this is the chatode of the voltage. 
this means the K+ is the anode of the cell

hope this helps

An ion is an atom that has a net positive or negative electric charge (true/false)

Answers

That statement is true. Hope I was of assistance :)

Select all the properties of a shield volcano listed below.
A. Basaltic lava
B. Violent eruptions
C. Layered structure
D. Found around the Ring of Fire
E. Large amounts of pyroclastic material

Answers

A. Basaltic lava her u go

Answer:

Option (A), (C) and (D)

Explanation:

Shield volcanoes are generally characterized gentle slopes, and are dome shaped, resembling the shield that is used by the ancient warriors. This type of volcano produces magma that are basaltic in nature and have no silica content. So they can flow easily. The layers are often formed due to the gentle eruption of lava that solidifies. These volcanoes are not explosive but they can turn into a violent one if it comes in contact with water. They occur along the Pacific's ring of fire. The amount of pyroclastic materials is less than the total amount of lava it releases during a volcanic eruption.

Thus, the correct answers are options (A), (C) and (D).

What corresponds to a pressure of 1.23atm

Answers

1.23atm = 1.246297623 bars

To convert from atm to bars, you just need to multiply the value in atms by 1.0132501 

So, 1.23 atms, = 1.23 × 1.0132501= 1.246297623 bars.

Which is a characteristic of a metal?

Answers

Some characteristics of a metal include
- They are ductile(pulled into wires), malleable( beaten into sheets)and    sonorous
-Good conductors of heat and electricity(makes them useful in electrical      appliance,
-Lustrous - Their surface shines when polished
-Have high melting and boiling points.

:)

Metal are good conductor of heat and electricity. They have lusture, hard and they are ductile and malleable.

What are metals?

Metals are good conductors of heat and electricity. The some of the characteristic of metal are:

Luster: Metals, such as gold, silver, and copper, have the ability to reflect light from their surface.

Metals that are malleable can endure hammering and be formed into thin foil-like sheets.

High melting and boiling points are characteristics of metals. The highest melting and boiling points are found in tungsten, whereas mercury has the lowest. Low melting points are also found for sodium and potassium.

Therefore, Metal are good conductor of heat and electricity. They have lusture, hard and they are ductile and malleable.

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PLZZZ HELP ME!!!!
Newton’s first law states that an object in motion will continue at the same speed and in the direction unless it is acted upon by a(n) _________________________ force.

Answers

The correct answer is ''External''.

An atom of strontium has at least four different isotopes. What is different between an isotope of 88Sr and an isotope of 84Sr?

Answers

Final answer:

Isotopes are forms of an element with the same number of protons, but different numbers of neutrons. The difference between 88Sr and 84Sr is in the number of neutrons, with 88Sr having 50 neutrons and 84Sr having 46 neutrons. This affects their physical properties but not their chemical behavior.

Explanation:

The difference between an isotope of 88Sr and an isotope of 84Sr lies in the number of neutrons each isotope contains. Isotopes are different forms of an element that have the same number of protons but a different number of neutrons. In the case of strontium (Sr), the atomic number is 38 which means it has 38 protons. For 88Sr, subtracting the number of protons (38) from the mass number (88), we find that this isotope has 50 neutrons. For the isotope 84Sr, it has 46 neutrons (84-38). The difference in the number of neutrons results in different physical properties, but does not affect the chemical behavior of the isotopes.

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The following is an example of what type of chemical reaction?
CH4 (g) + 2O2 (g) CO2 (g) + 2H2O (g)
Select one:
a. Single replacement
b. Decomposition
c. Double replacement
d. Combustion

Answers

This is a D. combustion reaction

That is because you add O2 which is necessary for a combustion, while the results are CO2 and water. What you are missing is a ---> after the 2O2 (g)

A single atom of platinum has a mass of 3.25 x 10^-22 g. What is the mass of 6.0 x 10^23 platinum atoms?

Answers

3.25 x 10^-22 g/atom times 6.0 x 10^23 atoms/mole = the answer you seek
The answer is 1.95 × 10² g

1 atom = 3.25 × 10⁻²² g
6.0 × 10²³ atoms = x g

1 atom : 3.25 × 10⁻²² g = 6.0 × 10²³ atom : x
x = 3.25 × 10⁻²² g × 6.0 × 10²³ atom : 1 atom
x = 3.25 × 6 × 10²³⁻²² g
x = 19.5 × 10 g
x = 1.95 × 10 × 10 g
x = 1.95 × 10² g

When glucose is completely oxidized with excess oxygen what are the products?

Answers


These are some of the results that may happen

The products of the oxidation of glucose with an excess of oxygen are carbon dioxide and water.

What is the combustion reaction?

A combustion reaction can be defined as a reaction that produces heat and occurs at an elevated temperature. It is an exothermic reaction, a redox chemical reaction that occurs between a fuel (hydrocarbon) and oxygen in the atmosphere.

Oxygen is an essential component for combustion because combustion cannot take place in the absence of oxygen. Complete combustion occurs when hydrocarbon burns fully to form water, carbon dioxide, and heat.

The burning of wood is also combustion where the carbon present in wood reacts with oxygen gas in the air to liberate heat and form gaseous products.

During the combustion of glucose reacts with an excess of oxygen gas to give six molecules of carbon dioxide and six molecules of water.

[tex]C_6H_{12}O_6 + 6O_2 \longrightarrow \; 6CO_2 + 6H_2O[/tex]

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State the three rules that define how electrons are arranged in atoms

Answers

The three correct rules or principles are the Aufbau Principle, Hund’s Rule, and the Pauli Exclusion Principle. Aufbau’s Principle states that each electron orbits the lowest energy orbital. It also states that all orbitals related to an energy level are of equal energy. Hund’s Rule states that single electrons with the same spin must occupy each equal-energy orbital before additional electrons with opposite spins can occupy the same orbitals. And finally, the Pauli Exclusion Principle states that a maximum of two electrons may occupy a single orbital, but only if the electrons have opposite spins. Hope this helps.

The three rules that define that how the electrons are arranged in atoms are the Aufbau Principle, Hund's rule, and the Pauli Exclusion Principle.  

• According to the Aufbau Principle, each electron holds the lowest energy orbital, and all the orbitals associated with an energy level are of the same energy.  

• According to Hund's rule, the single electrons with a similar spin must attain the equal energy orbital before the other electrons with the contrasting spins can attain similar orbitals.  

• According to the Pauli Exclusion principle, only a maximum of up to two electrons can occur in a single orbital, and only if the electrons exhibit opposite spins.  

Thus, the three rules, which illustrate that how the electrons are aligned in atoms are the Aufbau Principle, Hund's Rule, and the Pauli Exclusion Principle.

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What's the atomic mass unit of helium?

Answers

4.002602 u ± 0.000002 u

2 CuCl2 + 2 NaNO3 ---> Cu(NO3)2 + 2 NaCl


If 15 grams of copper (II) chloride react with 20 grams of sodium nitrate, How many grams of NaCl is formed

Answers

I hope you know the concept of limiting reagent. It is one of the simplest method to solve stoichiometric problems ;-)

According to the stoichiometry of the given chemical equation, 7.64 grams of NaCl is formed.

What is chemical equation?

Chemical equation is a symbolic representation of a chemical reaction which is written in the form of symbols and chemical formulas.The reactants are present on the left hand side while the products are present on the right hand side.

A plus sign is present between reactants and products if they are more than one in any case and an arrow is present pointing towards the product side which indicates the direction of the reaction .There are coefficients present next to the chemical symbols and formulas .

As per the equation, 268.9 grams copper chloride gives 137 g so 15 g copper chloride will give 15×137/268.9=7.64 g.

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Write a balanced overall reaction from these unbalanced half-reactions.
Sn->Sn2+ Ag+->Ag Balanced overall equation I got Sn+2Ag+->Sn+2Ag, but its wrong.

Answers

Answer: Sn + 2Ag⁺ → Sn²⁺ + 2 Ag


Explanation:


1) The half-reactions given are:


Sn → Sn²⁺


Ag⁺ → Ag


2) The first step that you should perform is to complete each half reaction with electrons to balance the charges. This is how:


Sn → Sn²⁺ + 2e⁻


Ag⁺ + 1e⁻ → Ag


3) The second step is to multiply the half-reactions by the appropiate coefficients to make the electrons on both reactions equal.


So, multiply the second reaction by 2:


Sn → Sn²⁺ + 2e⁻


2Ag⁺ + 2e⁻ → 2Ag


4) The third step is to add up the two equations:


Sn + 2Ag⁺ + 2e⁻ → Sn²⁺ + 2e⁻ + 2 Ag


5) Fourth step, cancell the electrons on both sides:


Sn + 2Ag⁺ → Sn²⁺ + 2 Ag


And that is the final answer.

The balanced overall equation for the two half reactions is:

Sn + 2Ag⁺ → Sn²⁺ + 2Ag

We'll begin by balancing the various half reactions. This can be obtained as follow:

Sn → Sn²⁺ + 2e¯...... (1)

Ag⁺ + → Ag .......... (2)

Multiply equation (2) by 2 to balance the electron(s) on both equation

Sn → Sn²⁺ + 2e¯...... (1)

2Ag⁺ + 2e¯ → 2Ag .......... (2)

Combine equation 1 and 2 with the elimination of 2e¯ to obtain the overall reaction as shown below:

Sn + 2Ag⁺ + 2e¯ → Sn²⁺ + 2Ag + 2e¯

Sn + 2Ag⁺ → Sn²⁺ + 2Ag

Therefore, the balanced overall equation for the two half reactions is:

Sn + 2Ag⁺ → Sn²⁺ + 2Ag

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what is the orbital diagram for phosphorus

Answers

The orbital diagram for phosphorus consists of five electrons in the third shell, eight in the second and two in the first shell, closest to the nucleus. The atomic number of phosphorus is 15. This number indicates the total number of electrons.
 
Ta Da!!!

Just do a little research!!! 

Or not you know, that's what we're here for...

What is the empirical formula for a compound if a sample contains 3.72 g of P and 21.28 g of Cl?

Answers

3.72/30.97=0.120/0.120=1
21.28/35.45=0.600/0.120=5

PCl5

Answer:

PCI5

Explanation:

Determine the number of moles of compound in each of the following samples.?
4.50g H2O
471.6g Ba(OH)2
129.68g Fe3(PO4)2

Answers

Explanation:

To calculate the number of moles, we use the equation:

[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex]    ......(1)

For 1: 4.50 g of water

Given mass of water = 4.50 g

Molar mass of water = 18 g/mol

Putting values in equation 1, we get:

[tex]\text{Moles of }H_2O=\frac{4.50g}{18g/mol}=0.25mol[/tex]

Hence, the moles of given amount of water is 0.25 moles.

For 2: 471.6 g of barium hydroxide

Given mass of barium hydroxide = 471.6 g

Molar mass of barium hydroxide = 171.34 g/mol

Putting values in equation 1, we get:

[tex]\text{Moles of }Ba(OH)_2=\frac{471.6g}{171.34g/mol}=2.75mol[/tex]

Hence, the moles of given amount of barium hydroxide is 2.75 moles.

For 3: 129.68 g of iron phosphate

Given mass of iron phosphate = 129.68 g

Molar mass of iron phosphate = 150.82 g/mol

Putting values in equation 1, we get:

[tex]\text{Moles of }Fe_3(PO_4)_2=\frac{129.68g}{150.82g/mol}=0.86mol[/tex]

Hence, the moles of given amount of iron phosphate is 0.86 moles.

What are the heaviest and lightest gases at standard conditions? ...?

Answers

The molecular weight I'm guessing you want: 

Nitrogen = 28.0134 
Oxygen = 31.9988 
Carbon Dioxide = 44.01 
Ammonia = 17.02 
Propane = 44.097 

Therefore Propane is the heaviest and Ammonia the lightest.


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Which of the following molecules has correctly labeled bond dipoles?

Answers

Final answer:

The bond dipole moment determines the molecular polarity of diatomic molecules. Homonuclear diatomic molecules have no difference in electronegativity and therefore have a dipole moment of zero. Heteronuclear molecules have a small dipole moment, while molecules with a larger electronegativity difference have a larger dipole moment.

Explanation:

For diatomic molecules, there is only one bond, so its bond dipole moment determines the molecular polarity. Homonuclear diatomic molecules such as Br2 and N₂ have no difference in electronegativity, so their dipole moment is zero. For heteronuclear molecules such as CO, there is a small dipole moment. For HF, there is a larger dipole moment because there is a larger difference in electronegativity.

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Chemistry Help?
The chemical formulae of some chemical compounds are written in the first column of the table below. Each compound is soluble in water.
Imagine that a few tenths of a mole of each compound is dissolved in a liter of water. Then, write down in the third column of the table the chemical formula of the major chemical species that will be present in this solution.
Note: "major" chemical species are those present in concentrations greater than 10^-6 mol/L

C3H6(OH)2 : ?
FeI3 : ?
C3H8O : ?

Answers

1) C3H6(OH)2 : this compound must be propan-1,2-diol or propylene glycol

This is covalent compound and will not dissociate in water so the chemical speceis present will be

H2O and C3H6(OH)2

2) FeI3: this is ionic compound and will dissociate to form

FeI3 ---> Fe+3  + 3I-

chemical species present : H2O , Fe^+3 and I^-1

3) C3H8O : this must be propanol again it will remain undissociated

so the chemical species present will be HeO and C3H6(OH)2

(1) The chemical species present will be [tex]\boxed{{{\text{H}}_{\text{2}}}{\text{O}}}[/tex] and [tex]\boxed{{{\text{C}}_{\text{3}}}{{\text{H}}_{\text{6}}}{{\left( {{\text{OH}}} \right)}_{\text{2}}}}[/tex].

(2) The chemical species present will be [tex]\boxed{{\text{F}}{{\text{e}}^{{\text{3}} + }}}[/tex], [tex]\boxed{{\text{3}}{{\text{I}}^ - }}[/tex] and [tex]\boxed{{{\text{H}}_{\text{2}}}{\text{O}}}[/tex].

(3) The chemical species present will be [tex]\boxed{{{\text{H}}_{\text{2}}}{\text{O}}}[/tex] and [tex]\boxed{{{\text{C}}_{\text{3}}}{{\text{H}}_{\text{8}}}{\text{O}}}[/tex]. For table (refer to the image attached).

Further Explanation:

Covalent compounds are those compounds which are formed by the electron sharing between two or more non-metals. Covalent bonds involve two atoms that share electrons and reach a more stable electron configuration

Ionic compounds are those compounds formed from the ions of the species. Ions are the species that are formed due to the loss or gain of electrons. Cation forms by the loss of electrons and anion forms by the gain of electrons in a neutral atom. The ionic bond is a chemical bond between two atoms in which one atom donates its electron to another atom.

Compounds made from two elements can either have an ionic or covalent bond.

(i) If a bond is formed from a metal and a non-metal then it will be ionic.

(ii)If a bond is formed from two non-metals then it will be covalent.

Ionic reaction:

The ionic reaction is a chemical reaction in which molecules dissociate into ions in water. In ionic reaction, net charge is same on both sides.

(1)  [tex]{{\mathbf{C}}_{\mathbf{3}}}{{\mathbf{H}}_{\mathbf{6}}}{\left( {{\mathbf{OH}}} \right)_{\mathbf{2}}}[/tex]

In [tex]{{\text{C}}_{\text{3}}}{{\text{H}}_{\text{6}}}{\left( {{\text{OH}}} \right)_{\text{2}}}[/tex], carbon (C), oxygen(O) and hydrogen(H) are nonmetals and form covalent bonds. Therefore, [tex]{{\text{C}}_{\text{3}}}{{\text{H}}_{\text{6}}}{\left( {{\text{OH}}} \right)_{\text{2}}}[/tex] is a covalent compound and will not dissociate in water. The chemical species present will be [tex]{{\text{H}}_{\text{2}}}{\text{O}}[/tex] and [tex]{{\text{C}}_{\text{3}}}{{\text{H}}_{\text{6}}}{\left( {{\text{OH}}} \right)_{\text{2}}}[/tex].

(2)  [tex]{\mathbf{Fe}}{{\mathbf{I}}_{\mathbf{3}}}[/tex]

In [tex]{\text{Fe}}{{\text{I}}_{\text{3}}}[/tex], Iron (Fe) is metal and iodine (I) is a nonmetal and they will form an ionic compound. Therefore, [tex]{\text{Fe}}{{\text{I}}_{\text{3}}}[/tex] is an ionic compound and will dissociate into ions in water.

The dissociation reaction of [tex]{\text{Fe}}{{\text{I}}_{\text{3}}}[/tex] into ions is as follows:

[tex]{\text{Fe}}{{\text{I}}_{\text{3}}} \to {\text{F}}{{\text{e}}^{{\text{3}} + }} + {\text{3}}{{\text{I}}^ - }[/tex]

Hence, the chemical species present will be [tex]{\text{F}}{{\text{e}}^{{\text{3}} + }}[/tex], [tex]{\text{3}}{{\text{I}}^ - }[/tex] and [tex]{{\text{H}}_{\text{2}}}{\text{O}}[/tex].

(3) [tex]{{\text{C}}_{\text{3}}}{{\text{H}}_{\text{8}}}{\text{O}}[/tex]  

In [tex]{{\text{C}}_{\text{3}}}{{\text{H}}_{\text{8}}}{\text{O}}[/tex] carbon (C), oxygen (O) and hydrogen (H) are nonmetals and form covalent compound. Therefore, [tex]{{\text{C}}_{\text{3}}}{{\text{H}}_{\text{8}}}{\text{O}}[/tex] is a covalent compound and will not dissociate in water. The chemical species present will be [tex]{{\text{H}}_{\text{2}}}{\text{O}}[/tex] and [tex]{{\text{C}}_{\text{3}}}{{\text{H}}_{\text{8}}}{\text{O}}[/tex].

The table that shows the chemical species present in each compound is attached in the image.

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2. Whether carbon dioxide and water have the same geometry or not: https://brainly.com/question/2176581

Answer details:

Grade: High School

Subject: Chemistry

Chapter: Chemical bonding and molecular structure

Keywords: Ionic, covalent, metal, nonmetal, water, ions, dissociation, C3H8O, FeI3, and C3H6(OH)2.

explain the process of saponification?

Answers

Saponification is the process of making soap. When an oil/fatty acid such as olive oil, mixed with a base (such as lye), and heated up, two products are made. One of the two products made from that mixture is fatty acid salt, or soap as it's commonly identified as. The second is glycerol which has a low toxicity. During the saponification process, the mixture has an acidity, which tells that it's not safe for usage. After the saponification process is complete, the pH should be a base.

Why do elements in a group on the periodic table have similar chemical properties?
a. similar atomic masses
b. similar atomic numbers
c. same number of outermost electrons
d. same number of protons

Answers

The answer is: [C]: "same number of outermost electrons".
_________________________________________________

One of the isotopes of sulfur is represented as sulfur-35 or S-35. What does the number 35 signify?

Answers

It signifies the Mass number

Final answer:

The number 35 in sulfur-35 represents the mass number of the isotope, which is the total number of protons and neutrons in the nucleus. Sulfur, with atomic number 16, has 19 neutrons in this isotope.

Explanation:

The number 35 in the isotope sulfur-35 or S-35 signifies the mass number of the isotope. The mass number is the sum of the number of protons and neutrons in an atom's nucleus. Sulfur's atomic number is 16, meaning it has 16 protons. To find the number of neutrons in sulfur-35, we subtract the atomic number from the mass number, yielding 35 - 16 = 19 neutrons. Sulfur has several isotopes, including sulfur-32, sulfur-33, sulfur-34, and sulfur-36, with varying neutron numbers and natural abundances. Sulfur-35 is a less common isotope and is not found in significant abundance.

Which of the answer choices accurately describes a trend that occurs when moving left to right across periods?

(Select all that apply.)

reactivity increases
atomic radius increases
atomic mass increases
valence electrons decrease

Answers

atomic radius is the correct answer

Moving left to right across a period on the periodic table, atomic radius decreases due to a stronger nuclear pull on electrons, while atomic mass increases because of the addition of protons and neutrons.

Two key factors affecting these trends include the increase of the atomic number (Z) and the effective nuclear charge felt by valence electrons. As a result, several trends can be observed:

Reactivity does not uniformly increase; it typically decreases for metals and increases for nonmetals.

Atomic radius decreases due to the increasing effective nuclear charge.

Atomic mass increases because elements have more protons, neutrons, and electrons.

Valence electrons generally increase, not decrease, as we add more electrons to fill the outermost shell.

When considering the provided trends, atomic radius decreasing and atomic mass increasing are trends that accurately describe what happens when moving left to right across a period. The atomic radius decreases mainly because a greater nuclear charge exerts a stronger pull on the electrons, drawing them closer to the nucleus. As the atomic mass increases, this is because protons and neutrons are being added to the nucleus as you move across the period. While reactivity varies depending on the type of elements (metals or nonmetals), we know that valence electrons actually increase as we move across a period, which is contrary to one of the listed answer choices.

(Refer to attachment)

1. List the windows in order of decreasing density.
2. Compare the density of the gas in window (a) to the density of gas in window (b).

Answers

In order from greatest to least density:
B→ C → A

The density of the gas in window (b) is greater than that in window (a) because it has a greater number of particles per unit volume in window (b) than in window (a).

4.What did J. J. Thomson observe when he applied electric voltage to a cathode ray tube in his famous experiment?

A.The stream of cathode ray particles was moving very slowly.
B.The glass opposite of the negative electrode started to glow.
C.The electric voltage had little effect on the stream of particles.
D.The tube contained two pieces of metal that served as electrodes.

11.The table below gives the data that is needed to calculate the average atomic mass of element B.

B-10(Isotope), 10.01(Atomic mass), 19.91(Relative abundance %)
B-11(Isotope), 11.01(Atomic mass), 80.09(Relative abundance %)

Answers

Answer 4:

Correct option is B

B.The glass opposite of the negative electrode started to glow.

Explanation:

In his experiment, tubes were two electric plates, producing a positive anode and a negative cathode, which he expected that it would deflect the rays. As he supposed, the rays were deflected by the electric charge, proving beyond doubt that the rays were made up of charged particles bearing a negative charge.

Answer 11:

Boron is a chemical element in the periodic table with symbol B and has atomic number 5.

Boron has two naturally occurring isotopes Boron-10 and Boron-11. The average atomic mass of these are calculated as

(10.01×0.198) + (11.01×0.802) =  10.81 amu

So, the average atomic mass of the Boron isotopes is 10.81 amu.

Answer:

The answer is b

Explanation:

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A system of equations is graphed on the coordinate plane.y=6x3 y=x+2What is the solution to the system of equations?Enter the coordinates of the solution in the boxes. what are equivalent fractions Which of the following is not the correct name for the line segment? MH MH with aline above it line segmant MH or HM with a line above it . In Florida, No-Fault insurance is optional for owners of a vehicle.A. TrueB. False 39 divided by 5 remainder Please Help!!!!How did Egyptian artists and architects create works that reflect the beliefs of ancient Egyptian civilization?A. The featured many kinds of animals to show their importance in Egyptian civilizationB. They commemorated military heroes, reflecting their high craftsmen played in Egyptian civilization. C. They focused on the important role that laborers and craftsmen played in Egyptian civilizationD. They glorified Egyptian royalty and gods to reflect their importance in society Which transport process does the cell use to direct the contents of vesicles out of the cell membrane? A.Endocytosis B.Diffusion C.Exocytosis D.Passive transport What is the change in elevation from 134 feet below sea level to 29 feet above sea level? When writing a book review, the best first step is to a. introduce your reasons for liking or not liking the book's author. b. summarize the plot of the book. c. introduce the subject and the type of book you are reviewing. d. review the story line of the book.? An author will almost always tell the reader the theme outright.TrueFalse what did the Babylonians develop through their study of astronomy A. the first 12-month calendar B. a calendar that predicted lunar eclipses C. a theory that the earth revolved around the sun D. a telescope to observe the planets What is 1 1/2 plus 2/3? Which of the following is considered technology? a. a computer c. a pencil b. a spoon d. all of the above A new savings account is opened with $300 and gains 3.1% yearly for 5 years You realize that more than 8000 gallons per year was a lot of water to waste with a leaky faucet. You fixed your faucet so that it now takes 11 minutes longer to fill a cup of water than it did when it leaked 1 fluid ounce 30 seconds. How many gallons will the faucet waste in 1 year? An object moves in a circle of radius R at constant speed with a period T . If you want to change only the period in order to cut the object's acceleration in half, the new period should be A ball is dropped from a height of 100 ft. one second later another ball is dropped from a height of 75 ft, which one hits the ground first? ...? Which statement best describes the organelles in a cell?A.All organelles are involved directly with communication between cells.B.Organelles must work together and their activities must be coordinated.C.Organelles function only when there is a disruption in homeostasis.D.Each organelle must function independently of the others in order to maintain homeostasis. 4. Which of the following sets of numbers is a Pythagorean triple? A. 4, 5, 6 B. 8, 15, 17 C. 5, 12, 14 D. 8, 24, 25Suppose a triangle has side lengths 6, 7, and 10. Which of the following best describes this triangle? A. obtuse B. acute C. right D. Cannot be determined. 20% of what number is 47?Need help