boron has two naturally occurring isotopes: boron -10 (abundance = 19.8% , mass = 10.013 amu) boron -11 (abundance = 80.2%, mass= 11.009 amu) Calculate th eatomic mass of boron

Answer:

The words science and technology can and often are used interchangeably. But the goal of science is the pursuit of knowledge for its own sake while the goal of technology is to create products that solve problems and improve human life. Simply put, technology is the practical application of science.

Explanation:

Check the following images

Hope it helps!!!

Please mark it as Brainliest ( the crown icon)

Answer:

Light travels as a wave.

Explanation:

But unlike sound waves or water waves, it does not need any matter or material to carry its energy along. This means that light can travel through a vacuum—a completely airless space. (Sound, on the other hand, must travel through a solid, a liquid, or a gas.)

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.

Answer:

The hydronium ion concentration increases to 100 times the original concentration

Explanation:

The pH of a solution is defined as the negative logarithm of the hydrogen or hydronium ion concentration of that solution. It is given by the expression below:

pH = -log[H₃O⁺] = log[H₃O⁺]⁻¹

Assuming the solution was at neutral with original pH = 7;

The new pH of the solution will be = 7 - 2 = 5

At pH = 7;

log[H₃O⁺]⁻¹ = 7

[H₃O⁺]⁻¹ = 10⁷

[H₃O⁺] = 10⁻⁷

At pH = 5

log[H₃O⁺]⁻¹ = 5

[H₃O⁺]⁻¹ = 10⁵

[H₃O⁺] = 10⁻⁵

10⁻⁵ = 10⁻⁷ * 10²

But 10² = 100

Therefore, the hydronium ion concentration increases to 100 times the original concentration

Answer:

B

Explanation:

On Edge

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

Answer:

[tex]\Large \boxed{\mathrm{A}}[/tex]

Explanation:

Rust formed from iron and oxygen combining is a chemical change, because in a chemical change, the resulting substance(s) will have different properties from the substance(s) before the chemical change.

I cant comment... So is it Right?

Answer:

Central

Explanation:

Chemistry is often called the central science because of connects the physical sciences, life sciences and applied sciences.

Chemistry is the study of matter and changes undergone by matter. This makes chemistry to occupy a central place in many scientific disciplines including medicine, engineering, pharmacy, geology etc. Basic knowledge of chemistry is usually required by experts in these disciplines.

Answer:

The answer is "Option B"

Explanation:

From the query, the following knowledge is derived:  

Yield in percentage = 47%  

Performance of theory = 4860 g  

Actual yield Rate =?  

The percentage return is defined simply by the ratio between both the real return as well as the conceptual return multiplied by the 100. It's also represented as numerically:

[tex]Rate = \frac{Existing \ Rate} {Theoretical \ Rate} \times 100[/tex]

Now We can obtain the percent yield as followed using the above formula:  

[tex]\text{Yield in percentage}= \frac{Actual \ yield \ Rate} {Theorical \ Rate} \times 100[/tex]

[tex]47\% = \frac{Actual \ yield \ Rate}{4860}[/tex]

The value of the Actual yield Rate =[tex]47\% \times 4860[/tex]

                                                        [tex]= \frac{47}{100} \times 4860 \\\\ = 2284.2 g[/tex]

The Actual yield Rate= 2284.2 g.

Answer:

In chemistry the reactivity series is an empirical, calculated, and structurally analytical progression of a series of metals, arranged by their "reactivity" from highest to the lowest.

Answer:

In a reactivity series, the most reactive element is placed at the top and the least reactive element at the bottom. More reactive metals have a greater tendency to lose electrons and form positive ions.

A reactivity series of metals could include any elements. For example,

A list of elements from most reactive to least reactive: potassium, sodium, lithium, calcium, magnesium, aluminum, zinc, iron, copper, silver, and gold.

A good way to remember the order of a reactivity series of metals is to use the first letter of each one to make up a silly sentence. For example, People Say Little Children Make A Zebra Ill Constantly Sniffing Giraffes.

Observations of the way that these elements react with water, acids, and steam enable us to put them into this series.

The tables show how the elements react with water and dilute acids:

Element Reaction with water

Potassium Violently

Sodium Very quickly

Lithium Quickly

Calcium More slowly

Element Reaction with dilute acids

Calcium Very quickly

Magnesium Quickly

Zinc More slowly

Iron More slowly than zinc

Copper Very slowly

Silver Barely reacts

Gold Does not react

Note that aluminum can be difficult to place in the correct position in the reactivity series during these experiments. This is because its protective aluminum oxide layer makes it appear to be less reactive than it really is. When this layer is removed, the observations are more reliable.

Non-metals in the reactivity series

It is useful to place carbon and hydrogen into the reactivity series because these elements can be used to extract metals.

Here is the reactivity series including carbon and hydrogen:

A list of elements from most reactive to least reactive: potassium, sodium, lithium, calcium, magnesium, aluminum, carbon, zinc, iron, hydrogen, copper, silver, and gold.

Note that zinc and iron can be displaced from their oxides using carbon but not using hydrogen. However, copper can be extracted using carbon or hydrogen. Displacement reactions of metal oxides

A more reactive metal will displace a less reactive metal from a compound. The thermite reaction is a good example of this. It is used to produce white-hot molten (liquid) iron in remote locations for welding. A lot of heat is needed to start the reaction, but then it releases an incredible amount of heat, enough to melt the iron.

aluminium + iron(III) oxide → iron + aluminium oxide

2Al + Fe2O3 → 2Fe + Al2O3

Because aluminum is more reactive than iron, it displaces iron from iron(III) oxide. The aluminum removes oxygen from the iron(III) oxide:

iron is reduced

aluminum is oxidized

Reactions between metals and metal oxides allow us to put a selection of metals into a reactivity series. Using metals A, B, and C:

Metal A Metal B Metal C

A oxide X Displaces A Displaces A

B oxide No reaction X No reaction

C oxide No reaction Displaces C X

Metal A cannot displace either B or C - so it must be the least reactive and be at the bottom of this reactivity series.

Metal B displaces both A and C - so it must be the most reactive and be at the top of this reactivity series.

Metal C displaces A but cannot displace B - so it must be more reactive than A but less reactive than B, and be in between them in this reactivity series.

In general, the greater the difference in reactivity between two metals in a displacement reaction, the greater the amount of energy released.

Aluminum is much higher than iron in the reactivity series, so the thermite reaction releases a lot of energy. Magnesium is very high in the reactivity series, and copper is very low - so the reaction between magnesium and copper oxide is more violent.

Therefore, the order is:

A list of letters from most reactive to least reactive: B, C and A,

Displacement reactions of solutions

A more reactive metal will displace a less reactive metal from a solution of one of its salts. For example:

magnesium + copper(II) sulfate → copper + magnesium sulfate

Mg(s) + CuSO4(aq) → Cu(s) + MgSO4(aq)

In this reaction, the blue color of the copper(II) sulfate fades as it is used up (magnesium sulfate solution is colorless). We would also see copper metal forming.

Reactions between metals and solutions of metal salts allow us to put a selection of metals into a reactivity series. Using metals J, K, and L:

Metal J Metal K Metal L

J sulfate X No reaction No reaction

K sulfate Displaces K X Displaces K

L sulfate Displaces L No reaction X

Metal J displaces both K and L - so it must be the most reactive and be at the top of this reactivity series.

Metal K cannot displace either J or L - so it must be the least reactive and be at the bottom of this reactivity series.

Metal L displaces K but cannot displace J - so it must be more reactive than K but less reactive than J, and be in between them in this reactivity series.

- sorry I'm late and it's is long -_-||

Answer:

It loses kinetic energy.

Explanation:

The definition of heat is molecules moving fast, so it cooling would mean they slow down.

Answer:

B, It loses kinetic energy.

Explanation:

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.

Answer:

Option C.

Explanation:

The arrangement of electrons in their orbital follows certain rules.

The Hund's rule practically explained how electrons are distributed in their orbitals.

The Hund's rule states that electrons distributed among the orbitals of the same shell singly (without partner) before pairing occurs.

In the filling of these electrons in their orbitals, we fill in the electron without pairing first because electrons tends to repel each other before filling with the opposite spin as shown in the attached photo.

There are two types of ions in chemistry, one is cation and the other is anion. Anion is the negative charge ion. Therefore, the formula of hydrogen sulfite ion is HSO₃⁻

Chemical Compound is a combination of ions, ions forms by combination of element and element forms by combination of atoms in fixed proportion.

According to our question the chemical compound from which hydrogen sulfite ion is coming is sulfurous acid that is H₂SO₃. So to get hydrogen sulfite ion we need to remove one hydrogen ion that is H⁺ from the chemical compound sulfurous acid.

The balanced reaction is

H₂SO₃[tex]\rightarrow[/tex]H⁺ + HSO₃⁻

From above reaction we can see that the charge over hydrogen sulfite ion is -1

Therefore the formula of hydrogen sulfite is HSO3-

To learn more about chemical compound, here:

https://brainly.com/question/26487468

#SPJ6

Answer:

Proteins

Explanation:

Amino acids act as monomers (a single unit used to form polymers) , the polymer will be a long chain of individual amino acids. An amino acid chain forms a protein. These proteins are also known as peptides.

Hope this helps and please mark as the brainliest.

Answer:

When you don't have a complete reaction.

Explanation:

Happens a lot between a solvent and a solute. The solute may not bind well with the solvent I.e. water.

Answer:

50%

Explanation:

Expected measurement required = 10g

Actual measurement observed = 15g

The percentage error is given as proportion the difference between the actual and expected measurement or values and the expected value value expressed as a percentage.

[(Actual - Expected) / Expected] × 100%

[(15 - 10) / 10)] × 100%

(5 / 10) × 100%

0.5 × 100%

50%

Therefore, the percentage error in the measurement is 50%

Hey there!:

Mass = 0.6 g

Density = 0.0012 g/mL

Volume = ??

Therefore :

Density = mass / Volume

0.0012 = 0.6 / V

V = 0.6 / 0.012

V = 500 mL

Hope this helps!

Answer:

1.5g/cm³

Explanation:

density=mass÷volume

mass= 1.5kg (change into g) = 1500g

volume of the cube = 10×10×10 = 1000cm³

density= divide 1500g÷1000cm = 1.5g/cm³

YOUR WELCOME!

The density of the cube on Earth that weighs 1.5 kg and has a side length of 10 cm is 1.5g/cm³

"Density is the mass per unit volume. Density is a scalar quantity. It is denoted by d and the symbol for density is given as rho, a Greek symbol. Density is calculated as mass divided by volume."

density = mass / volume

The mass of the cube on earth is 1.5 kg

The side length of the cube is 10 cm.

The mass is given in kg. It is converted into grams.

mass= 1.5kg (change into g) = 1500g

A cube is a three-dimensional square, it has 6 faces, so its volume will be calculated completely.

Volume of the cube = 10×10×10 = 1000cm³

Putting the values in the formula of density

density= divide 1500g /1000cm = 1.5g/cm³

Thus, the density of the cube on Earth is 1.5g/cm³.

To learn more about density, refer to the link:

https://brainly.com/question/13291386

#SPJ2

Answer:

Smithers thinks that a special juice will increase the productivity of workers. He creates two groups of 50 workers each and assigns each group the same task (in this case, they're ... Group A is given the special juice to drink while they work. Group ... 1. Control Group. Group B. 2. Independent Variable. volume of special juice.

Explanation:

Answer:

1. Group B

2. The juice

3. The number of stacks of paper

4. the juice did not help improve a quicker process

5. Group A can be given the juice, Group B can be given the juice without the special ingredient

USE QUIZLET FLASH CARDS IT CAN HELP YOU WITH A LOT OF QUESTION

Answer:

Fórmula empírica: C₂H₂N

Fórmula molecular: C₄H₄N₂

Explanation:

Un compuesto que contiene carbono hidrógeno y nitrógeno con fórmula CₐHₓNₙ es sometido a combustion produciendo:

CₐHₓNₙ + O₂ → aCO₂ + x/2 H₂O + nNO₂

Con la masa de dióxido de carbono y agua podemos encontrar las moles de carbono e hidrógeno y su aporte a los 0.452g de muestra que fueron puestos en combustión, así:

Moles C:

Moles C = Moles CO₂ = 0.994g CO₂ ₓ (1mol / 44g) = 0.0226 moles C

Masa C: 0.0226 moles C ₓ (12.01g / mol) = 0.271g Carbono hay en la muestra

Moles H:

Moles H = 2 Moles H₂O = 0.203g H₂O ₓ (1mol / 18g) = 0.0113 moles H₂O = 0.0226 moles H

Masa H: 0.0226 moles H ₓ (1.01g / mol) = 0.023g Hidrógeno hay en la muestra

Así, la masa de nitrógeno en la muestra y sus moles son:

Masa N = 0.452g - 0.271g C - 0.023g H

Masa N = 0.158g Nitrógeno

Y su moles son:

0.158g ₓ (1 mol / 14.01g) = 0.0113 moles N

Con las moles de C, H y N podemos determinar la formula empírica que se define como: "La relación de números enteros más simple entre la cantidad de átomos presentes en una mólecula. Si usamos como base las moles de nitrógeno (Valor menor):

Relación H/N: 0.0226 mol / 0.0113 mol = 2

Relación C/N: 0.0226 mol / 0.0113 mol = 2

Relación N/N: 0.0113 mol / 0.0113 mol = 1

Así, la fórmula empírica es:

Esta fórmula empírica tiene una masa molar de:

2C = 2*12 g/mol = 24g/mol

2H = 2*1g/mol = 2g/mol

N = 14g/mol

24+14+2 = 40g/mol

Como la masa molecular del compuesto es 80g/mol (Dos veces la de la fórmula empírica, la fórmula molecular es 2 veces la fórmula empírica:

Explanation:

Yes, Na2 gas possesses a metallic character.

In the stable state, metal sodium functions as an array of Na+ ions which can be surrounded by way of a sea of 3s electrons. However, it would be wrong to consider metal sodium as an ion when you consider that the ocean of electrons is shared by using all of the sodium cations, quenching the nice fee.

Sodium most effective has one valence electron. So, in metallic bonding, it is able to only donate one electron to be delocalized at some point of the structure. In steel bonding, the real bonding is the electrostatic force between the effective cations and the delocalized electrons.

Learn more about metallic bonds here: https://brainly.com/question/20536777

#SPJ2

Answer:

Explanation:

Let the no in the ones place be x

And the no in the tens place be 10 - x

Original no = 10 ( 10 - x ) + x

= 100 - 10x + x

= 100 - 9x

Reversed no = 10 - x + 10 ( x )

= 10 - x + 10 x

10 + 9x

According to the question,

the new number formed exceeds the originals numbers by 54.

10 + 9x = 100 - 9x + 54

10 + 9x = 154 - 9x

By transposing,

9x + 9x = 154 - 10

18 x = 144

x = 144 / 18

x = 8

∴ Digit in ones place = x = 8

Digit in tens place = 10 - x = 10 - 8 = 2

So the number = 28

( You can also recheck it by adding the ones and tens digit

8 + 2 = 10

In the question, the sum of ones and tens digit in ten )

Hope this helps

plz mark as brainliest!!!!!!!

Answer:

Mass of chemical = 50 gram

Explanation:

Given:

Volume of chemical = 5 ml

Density of chemical = 10 g/mL

Find:

Mass of chemical

Computation:

Mass of chemical = Density of chemical × Volume of chemical

Mass of chemical = 10 × 5

Mass of chemical = 50 gram

Answer:

The correct option is;

3. A homogeneous mixture of two compounds

Explanation:

An homogeneous mixture is one where the components of the mixture are evenly dispersed such that the individual components cannot be seen to be isolated and distinguishable and having a constant composition of the constituents

The image displays three atoms (red circle, cyan triangle, and orange rectangle). The red circle appear to be bonded in pairs while the cyan triangles are bonded to the orange rectangles making a total of two compounds

The arrangement of the compounds in the mixture appear to be very evenly distributed to suggest an homogeneous mixture

The visibility of the compounds should be for an illustrative purpose.

Answer:

Option B

Explanation:

Let us go through each of the options individually.

option A.

he phases in a chemical reaction tell us the state of the reactants and the products.

This is true because phases representations such as s, l , g and q tells us the state of the reactants if they are in the solid or liquid or gaseous or aqueous state of matter respectively. So this is not our answer.

option B

An individual coefficient, with no reactant or product, in a balanced equation is meaningless.

This option is correct, because in every reaction, there must be the reactant and product present.

option C

The subscripts in a balanced equation tell us the number of atoms in a molecule.

This is correct. Consider the equation below;

2H₂ + O₂ --> 2H₂O

In the reactant phase, the subscripts tells us that we have just two atoms of oxygen present.

Answer:

4-phospho,Bromooctane

Answer:

The order of reaction is as follows, R1 = 1; R2 = 2; R3 = 0

Explanation:

The rate of a chemical reaction is the number of moles of reactants consumed per unit time or the number of moles of products formed per unit. the rate of a chemical reaction is affected by the concentration of reactants

The relationship between the rate of a chemical reaction and the concentration of its reactants is given by the rate law or equation.

Generally, the rate equation is given as;

Rate = k[A]ᵃ[B]ᵇ..., where k = rate constant which is independent of concentration of the reactants, [A] = concentration of reactant A, a = order of reaction A, [B] = concentration of reaction B, b = order of reaction B.

For the given reactions R1, R2 and R3

For R1; rate = 3, Concentration = 3[A]

3 = k[A]3ˣ

3¹ = k[A]3ˣ

Since rate is proportional to concentration, therefore, the order of reaction, x = 1

For R2; rate = 9, Concentration = 3[A]

9 = k[A]3ˣ

3² = k[A]3ˣ

Since rate is proportional to concentration, therefore, the order of reaction, x = 2

For R1; rate = 1, Concentration = 3[A]

1 = k[A]3ˣ

3⁰ = k[A]3ˣ

Since rate is proportional to concentration, therefore, the order of reaction, x = 0

Therefore, the order of reaction is as follows, R1 = 1; R2 = 2; R3 = 0

The correct answer is D. The native species would not have to  compete for necessary resources

Explanation:

Invasive species, which include any living organism that is not native in an ecosystem, contribute to the extinction of native species as they compete for resources such as food, shelter, etc. with native species. For example, the  Asian Carp, which was introduced to lakes in the U.S. consumes plankton, which reduces the amount of plankton available for native fish. In this context, by removing invasive species native species would not have to compete for resources and their chances to extinct will fall.