O Which of the following determines the
identity of an element?
a. atomic number
b. mass number
c. atomic mass
d. Overall changes

Answer:

The atomic number refers to the number of protons in the nucleus of an atom. The identity of an element is determined by its number of protons. The atomic number uniquely identifies a chemical element. It is identical to the charge number of the nucleus.

And if you want to mark someone's answer as brainliest first you have to get more than 1 answer to your question and then there will be a message above that says “Mark as brainiest”

A) CaCl2

Calcium chloride is an inorganic compound, a salt with the chemical formula CaCl2. It is a colorless crystalline solid at room temperature, highly soluble in water.

7.296 x 102 in scientific notation 23x1011 is obtained by dividing by 3.6 x 109.

Very big or very low numbers can be written using scientific notation. Once a number within 1 and 10 has been multiplied by such a power of 10, it is then expressed in scientific notation. For instance, the scientific notation for 650,000,000 is 6.5 108.

A system of symbols and signs is used in notation to represent words, numbers, sentences, etc. The efficient communication of words, figures, and other objects is greatly aided by notation, which is frequently created for a specific purpose. Music notation is a prime example of notation.

To know more about Notation visit:

https://brainly.com/question/18073768

#SPJ1

The molecule shape of SF6 is octahedral.

SF6 is a sulfur hexafluoride molecule, which is composed of a central sulfur atom surrounded by six fluorine atoms. In the SF6 molecule, the sulfur atom is bonded to the six fluorine atoms through strong covalent bonds.

The arrangement of these bonds gives SF6 an octahedral shape, with the six fluorine atoms positioned at the vertices of an imaginary octahedron and the sulfur atom at its center. The octahedral shape of SF6 is due to the symmetrical distribution of electron density around the central sulfur atom, which results in a sp3d2 hybridization state.

In summary, SF6 has an octahedral molecule shape, which is characterized by six equidistant vertices arranged symmetrically around a central atom.

Learn more about hybridization state here:

https://brainly.com/question/30323439

#SPJ4

Answer:

Avogadro's number

Explanation:

Avogadro's number

defined as the number of elementary particles (molecules, atoms, compounds, etc.) per mole of a substance. It is equal to 6.022×1023 mol-1 and is expressed as the symbol NA.

The equilibrium constant for the reaction is 28.44.

The equilibrium constant expression for the reaction is:

\(Kc = [C][D]/([A]^2[B]^3)\)

where [A], [B], [C], and [D] are the molar concentrations of the respective species at equilibrium.

At the start of the reaction, the initial concentrations of A and B are:

[A] = 2.0 moles / 2.00 L = 1.0 M

[B] = 3.0 moles / 2.00 L = 1.5 M

At equilibrium, the concentration of A is 0.400 mol / 2.00 L = 0.200 M.

We can use these initial and equilibrium concentrations to find the equilibrium concentration of C and D:

[C] = [D] = (2.0 - 0.400) mol / 2.00 L = 0.800 M

Now we can substitute these concentrations into the equilibrium constant expression:

\(Kc = [C][D]/([A]^2[B]^3)\)

\(= (0.800 M)^2 / (0.200 M)^2 (1.5 M)^3\)

= 28.44

For more question on equilibrium click on

https://brainly.com/question/19340344

#SPJ11

Answer:

hey have one valence electron

they are called alkali metals not Alkaline earth metals

they react with water

are metals

Explanation:

hope this helps

Answer:

I think c

Explanation:

The oceans have an almost unlimited buffering capacity for rather harmless phosphorus species and some marine life.

Most of them will benefit from increased phosphorus levels in rivers. The global average phosphate concentration in the oceans will increase by about 20 ppm if flows double. If the flow rate is doubled, the increase in concentration is only about 10 ppm.

If the concentration of phosphorus in rivers suddenly increases, the ocean will start absorbing phosphorus, and the temperature of the oceans will in turn rise, leading to further corrosion and the release of toxins that can kill marine life and even make people sick.

The global average phosphate concentration in the oceans would slowly decrease over time as the ocean slowly absorbs phosphorus and the concentration in rivers slowly decreases.

To know more about kinetic model:

brainly.com/question/17092980

#SPJ4

Answer:

The energy of the wave particle is 3.058 x 10⁻²³ J.

Explanation:

Given;

wavelength of the wave particle, λ = 6.5 x 10⁶ nm = (6.5 x 10⁶) x 10⁻⁹ m

The energy of the wave particle is calculated as;

\(E = hf\\\\E = \frac{hc}{\lambda}\)

where;

h is Planck's constant = 6.626 x 10⁻³⁴ J/Hz

c is speed of light = 3 x 10⁸ m/s

\(E = \frac{(6.626 \times 10^{-34})(3\times 10^8)}{6.5 \times 10^6 \times 10^{-9}} \\\\E = 3.058 \times 10^{-23} \ J\)

Therefore, the energy of the wave particle is 3.058 x 10⁻²³ J.

Answer:

2.5 silly = 0.00025 kilosilly

Explanation:

To convert: \(2.5\) silly to kilosilly

Solution:

Relation between \(2.5\) silly and kilosilly is given as follows:

1 silly = \(\frac{1}{1000}\) kilosilly

Now use this formula to convert \(2.5\) silly to kilosilly.

\(2.5\) silly\(=\) \(\frac{2.5}{1000}\) kilosilly

Here, \(\frac{2.5}{1000} =0.00025\)

So,

2.5 silly = 0.00025 kilosilly

The most abundant isotope among the given Isotopes will be Isotope B

To calculate the percent abundance of each isotope in a sample of an element, we usually divide the number of atoms of a particular isotope by the total number of atoms of all isotopes of that element and then multiply the result by 100.

% Abundance =  15/50 x 100

                        =  30 %

% Abundance =  30/50 x 100

                        =  60 %

% Abundance =  5/50 x 100

                        =  10 %

Hence, The most abundant isotope among the given Isotopes will be Isotope B.

Learn more about isotopes here ;

https://brainly.com/question/12955625

#SPJ1

In the electrophilic aromatic substitution reaction between benzaldehyde and Br2 in the presence of FeBr3, the first step involves the generation of a carbocation intermediate. This carbocation is formed when the bromine molecule attacks the benzene ring, displacing a proton.

Since benzaldehyde is a meta-director, the carbocation intermediate will be stabilized through resonance. The resonance structures can be represented as follows:

Structure 1:

      Br

       |

Ph-C(+)-H

       |

Structure 2:

      Br

       |

Ph-C-H

  |    |

  +    Ph

Structure 3:

      Br

       |

Ph-C-H

  |    |

Ph    +

In these resonance structures, the positive charge of the carbocation is delocalized throughout the benzene ring. The presence of the electron-withdrawing aldehyde group (CHO) in benzaldehyde directs the incoming bromine atom to the meta position relative to the aldehyde group.

Please note that it's always recommended to consult reliable sources and appropriate references for accurate structural representations.

To know more about carbocation visit:  

https://brainly.com/question/31827291

#SPJ11

Answer:

False

Explanation:

Alkynes are classified as terminal or internal depending on the position of the triple bond's carbon(C) atoms. If the triple bond is between the last two C in the chain, the alkyne is known as a terminal alkyne. If the triple bond is between carbons that are not the last in the chain, the alkyne is known as an internal alkyne.

Diastereomers are non-mirror image stereoisomers(si) that can't be superimposed on one another. This means that a six-C alkyne that can exist as diastereomers must have a minimum of two stereocenters. Therefore, a six-C alkyne that can exist as diastereomers is shown in the figure below: Explanation: A C-C triple bond characterizes an alkyne.

To know more about Diastereomers visit:

https://brainly.in/question/16580646

#SPJ11

(1a) 3-Chlorophenol is more acidic than cyclopentanol (chlorine atom electron-withdrawal). (1b) Cyclohexanecarboxylic acid is more acidic than cyclohexanol (stronger carboxylic acid group).

(2a) Propan-2-ol is more soluble in water than butan-1-ol and pentan-1-ol (hydrogen bonding ability). (2b) Cyclohexanol is more soluble in water than chlorocyclohexane (hydroxyl group enables hydrogen bonding).

Part 1: Comparing Acidic Strength

a) 3-chlorophenol is more acidic than cyclopentanol. This is because the presence of a chlorine atom in 3-chlorophenol can stabilize the negative charge on the phenoxide ion through inductive and resonance effects, making it more stable and easier to form.

b) Cyclohexanecarboxylic acid is more acidic than cyclohexanol. The carboxylic acid group (-COOH) is a stronger acid functional group compared to the hydroxyl group (-OH) present in cyclohexanol.

c) 2,2-dichlorobutan-1-ol is more acidic than butan-1-ol. The presence of the electron-withdrawing chlorine atoms in 2,2-dichlorobutan-1-ol enhances the acidity by stabilizing the negative charge on the alkoxide ion formed upon deprotonation.

d) Cyclohexanecarboxylic acid is more acidic than cyclohexanol. The carboxylic acid group (-COOH) is a stronger acid functional group compared to the hydroxyl group (-OH) present in cyclohexanol.

Part 2: Comparing Solubility in Water

a) Propan-2-ol is more soluble in water than butan-1-ol and pentan-1-ol. Propan-2-ol has a hydroxyl group (-OH) that can form hydrogen bonds with water molecules, increasing its solubility.

b) Cyclohexanol is more soluble in water than chlorocyclohexane. The presence of the hydroxyl group in cyclohexanol allows for hydrogen bonding with water molecules, enhancing its solubility. Chlorocyclohexane, on the other hand, is nonpolar and lacks the ability to form significant hydrogen bonds with water.

c) Cyclohexanol is more soluble in water than phenol and 4-methylcyclohexanol. Both cyclohexanol and phenol can form hydrogen bonds with water, but phenol's aromatic ring reduces its solubility. 4-methylcyclohexanol is also less soluble than cyclohexanol due to the steric hindrance from the methyl group, which disrupts hydrogen bonding.

To know more about the aromatic ring refer here,

https://brainly.com/question/32170261#

#SPJ11

The percent abundance for the other stable isotope of antimony is 121Sb = 57.2% and 123Sb = 42.8%.

Any of two or more species of atoms of a chemical element with the equal atomic quantity and nearly identical chemical conduct however with differing atomic mass or mass number and exceptional bodily isotope.

Given,

121.76amu is the average mass of all antimony isotopes.

x+y=1⇒y=1−x(both abundances add up to 100%),

=120.904x+122.904y=121.76

Using alzebra,

= 120.904x+122.904⋅(1−x)=121.76

∴x=0.572,

x+y=1

∴y≈0.428

changing into percentage = 0.428 *100 = 42.8%

Hence, 121Sb has a relative abundance of approximately 57.2%, and 123Sb has a relative abundance of approximately 42.8%.

Learn more about isotopes here:-https://brainly.com/question/14220416

#SPJ9

It takes approximately 100.704 years (since 1964) until only 9 percent of the original amount of radioactive strontium-90 absorbed remains.

The half-life of radioactive strontium-90 is given as 29 years, which means that every 29 years, the amount of radioactive strontium-90 is reduced by half.

To find the number of years it takes until only 9 percent of the original amount remains, we can set up the following equation:

(0.5)^(t/h) = 0.09

Where:

t represents the number of years since 1964 (the initial time),

h represents the half-life of 29 years, and

0.09 represents 9 percent.

Let's solve for t:

(0.5)^(t/29) = 0.09

Taking the natural logarithm (ln) of both sides:

ln[(0.5)^(t/29)] = ln(0.09)

Using the logarithmic property: ln(a^b) = b × ln(a):

(t/29) × ln(0.5) = ln(0.09)

Dividing both sides by ln(0.5):

t/29 = ln(0.09) / ln(0.5)

t = 29 × (ln(0.09) / ln(0.5))

Using a calculator, we can find the value of t:

t = 29 × (-2.40794561 / -0.69314718)

t = 100.704

Learn more about radioactive -

brainly.com/question/23759636

#SPJ11

Answer: Wowwwww

Explanation:yes

Answer:

They move freely between the clouds of several atoms, si the correcto Answer is D

Explanation:

Hope this helps.

Bach's cantatas were distinguished from the simple melodies of the Lutheran chorales on which they were based in several ways. These include the lush string accompaniments, a double chorus, the addition of counterpoint, and narration by a tenor evangelist.

Lush string accompaniments:

Bach's cantatas often featured lush string accompaniments. This helped to create a rich and complex sound that was very different from the simple melodies of the chorales on which they were based.

A double chorus:

Bach's cantatas also often featured a double chorus. This means that there were two choirs singing at the same time. This added to the complexity and richness of the music.

Addition of counterpoint:

Bach's cantatas also featured the addition of counterpoint. This is when two or more melodies are played at the same time. Bach was a master of counterpoint and used it to create complex and beautiful music.

Narration by a tenor evangelist:

Finally, Bach's cantatas often featured narration by a tenor evangelist. This is when a tenor singer tells the story of the cantata. This helped to make the cantatas more like operas and added to their dramatic effect.

In conclusion, Bach's cantatas were distinguished from the simple melodies of the Lutheran chorales on which they were based in several ways. These include the lush string accompaniments, a double chorus, the addition of counterpoint, and narration by a tenor evangelist.

To know more about Lutheran chorales visit:-

https://brainly.com/question/32350724

#SPJ11

The products Rosa recorded in the last row of the table should be: 2LiCl + 3O₂.

The type of reaction which Rosa did is a decomposition reaction which involves one compound that yields to more than one (or usually two) product. To determine the product, we can deduce that it has to contain elements of Li, Cl and O₂. So, from the options, the answer is 2LiCl + 3O₂.

A decomposition reaction can be described as a chemical reaction in which one reactant breaks down into two or more products. Generally, decomposition reactions need energy input.

Learn more about decomposition reaction at: https://brainly.com/question/16987748

#SPJ4

The particles in the solid are touching with very little space between them. The particles in a liquid usually are still touching but there are some spaces between them. The gas particles have big distances between them.

...

Liquids Solids and Gases:

NON OF THESE

The effects of exposure were more pronounced in fish that had been raised in a less stressful environment, suggesting that environmental conditions can influence the impact of exposure to antidepressants.

1. The class of drugs being investigated in this study is antidepressants. They enter our waterways through excretion by individuals taking the medication, and disposal of unused medication into toilets or sinks that are connected to wastewater treatment plants.

2. C-start is an evasive maneuver that young fish use when they perceive a predator. This is important for larval fish survival because it helps them to avoid being eaten by predators.

3. In this investigation, researchers are testing two hypotheses. The first is that exposure to low levels of antidepressants can affect larval fathead minnows' behavior, and the second is that the effects of exposure will be more pronounced in fish that have been raised in a less stressful environment.

4. The researchers found that exposure to antidepressants at levels found in waterways can have a significant impact on the behavior of larval fathead minnows. Specifically, they found that the fish exposed to antidepressants were less likely to respond to the presence of predators, which could increase their risk of being eaten.

They also found that the effects of exposure were more pronounced in fish that had been raised in a less stressful environment, suggesting that environmental conditions can influence the impact of exposure to antidepressants.

To learn more about antidepressants,

https://brainly.com/question/28209828

#SPJ4

Cancer is a group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body.[2][8] These contrast with benign tumors, which do not spread.[8] Possible signs and symptoms include a lump, abnormal bleeding, prolonged cough, unexplained weight loss, and a change in bowel movements.[1] While these symptoms may indicate cancer, they can also have other causes.[1] Over 100 types of cancers affect humans.[8]

Tobacco use is the cause of about 22% of cancer deaths.[2] Another 10% are due to obesity, poor diet, lack of physical activity or excessive drinking of alcohol.[2][9][10] Other factors include certain infections, exposure to ionizing radiation, and environmental pollutants.[3] In the developing world, 15% of cancers are due to infections such as Helicobacter pylori, hepatitis B, hepatitis C, human papillomavirus infection, Epstein–Barr virus and human immunodeficiency virus (HIV).[2] These factors act, at least partly, by changing the genes of a cell.[11] Typically, many genetic changes are required before cancer develops.[11] Approximately 5–10% of cancers are due to inherited genetic defects.[12] Cancer can be detected by certain signs and symptoms or screening tests.[2] It is then typically further investigated by medical imaging and confirmed by biopsy.[13]

Answer:

Graph is attached below.

Explanation:

Go to insert, then chart, then select line, then go to sheets and edit it to fit what you need it to say.

Hope this helps! Please let me know if you need more help, or if you think my answer is incorrect. Brainliest would be MUCH appreciated. Have a great day!

−xXheyoXx

In this question, we need to find the value of pressure of a 15 grams sample of CO2 gas, and in order to find this value, we will be using the Ideal gas law formula, which is the following:

PV = nRT

Where:

P = pressure in atm

V = volume in liters, 20 Liters

n = number of moles

R = gas constant, 0.082

T = temperature in kelvin, 0°C = 273 K

The number of moles we need to find based on the mass in the question and based on the molar mass of CO2, 44g/mol:

44g = 1 mol

15g = x moles

44x = 15

x = 15/44

x = 0.34 moles of CO2 in 15 grams

Now we have the values to add to the formula:

P * 20 = 0.34 * 0.082 * 273

20P = 7.61

P = 7.61/20

P = 0.38 atm of pressure

The pressure will be 0.38 atm

If the hydrogen gas is combusted and produces 645L of water vapor at 400 kelvin and 1.75 atm, 2796.96 g mass of the zinc is produced .

Using the ideal gas law equation:

PV = nRT

n = (PV) / (RT)

= (1.75 atm * 645 L) / (0.0821 atm·L/(mol·K) * 400 K)

= 42.71 moles

the balanced equation for the reaction between zinc and hydrochloric acid:

Zn + 2HCl -> \(ZnCl_{2}\)  + \(H_{2}\)

1 mole of zinc produces 1 mole of hydrogen gas. Therefore, the moles of zinc are also 42.71.

The molar mass of zinc is 65.38 g/mol.

Mass of zinc = moles of zinc * molar mass of zinc

= 42.71 moles * 65.38 g/mol

= 2796.96 g

Therefore, the mass of the zinc is 2796.96 grams.

learn more about hydrogen gas :

https://brainly.com/question/30829657