18. Which of these is an ion?
A. Fluorine with 9 protons
B. Calcium with 18 electrons
C. Calcium with 18 neutrons
D. Fluorine with 9 neutrons

Answers

Answer 1
It is c. Calcium with 18 neutrons

Related Questions

A sample of an ideal gas has a volume of 2.38 L at 283 K and 1.03 atm. Calculate the pressure when the volume is 1.97 L and the temperature is 307 K.

Answers

Gas Has A Volume Of 2.21 L At 287 K And 1.11 Atm. Calculate The Pressure When The Volume Is 1.03 L And The Temperature

Explanation:

In two to three sentences, explain the trend for atomic size. Why does this trend occur?

Answers

Answer:

The number of energy levels increases as you move down a group as the number of electrons increases. Each subsequent energy level is further from the nucleus than the last. Therefore, the atomic radius increases as the group and energy levels increase. 2) As you move across a period, atomic radius decreases.

Explanation:

True or false: An oxidation number is not the same as an actual charge on an ion. True false question. True False

Answers

Answer:

True

Explanation:

They are actually the same

The answer is False.

The oxidation number is the number of electrons removed or added to an element or compound. This is also equal to the charge on the ion.

For example, if Sodium atom loses one electron, it becomes oxidized to the + 1 state.

Na → Na⁺ + e⁻.

So, the oxidation number of Sodium is the charge on the Sodium ion which is + 1.

So, the oxidation number is equal to the charge on the ion.

So, the answer is False.

Learn more about oxidation number here:

https://brainly.com/question/166558

Which of the following is an example of work: bowling or reading? How do you know?

Answers

Both.. I know because reading you have to focus on the book and actually make your mind read the book and process what you are reading... Bowling is also an example of work because you have to focus on the ball and focus on where you roll the ball
I hope this helps! HAVE A GREAT DAY!!

Which changes MUST happen for elements to become a compound

Answers

Answer:

Chemical changes in compounds happen when chemical bonds are created or destroyed. Then the molecular structure changes; new molecules form and a new substance is created. Often heat is used to begin a chemical change, as when baking a cake. Another example of a chemical reaction is the rusting of a metal trash can.

Hope this helps you Do mark as brainliest ✌️

An element is constituted of only atoms and no other entities are present in it. Whereas a chemical compound is a substance made up of various identical molecules of the same or different atoms.

The atoms of the same or different species bond together to form a compound.

Chemical bonding is present among them that cannot be simply separated.

The compounds can have ionic, covalent and hydrogen bonds present in them.

When the new atoms combine the structure changes of the new molecule formed.

To learn more about compounds and atoms follow the link:

https://brainly.com/question/2481039

HELPPPPP plssssss!!!!!! Is the brain of the cell living or non-living?

Answers

Answer: living

Explanation: The brain of a cell is living. All parts of the cell must be alive in order for the human body to revive. The brain of a cell controls the cells, and cells are the basic block of human life.

Pure H2oboils at 100 ˚C and freezes at 0 ˚C. What is the melting point and boiling point of water
after the addition of potassium chloride​

Answers

Answer:

Recall the colligative properties of freezing point depression and boiling point elevation.

In proportion to the molality product of the solute, (

i

m

), the boiling point will raise and the freezing point will decrease.

Now, consider tap water. You know this!

Is tap water pure water? Of course not! It's a solution of many ions of metals or other inorganic compounds.

Hence, it has a varied boiling and melting point, by definition.

Explanation:

The colligative properties like the boiling point elevation and freezing point depression depend on the solute concentration. The boiling point of the water will increase while the freezing point will decrease.

What are colligative properties?

Colligative properties are the attributes that depend on the amount or the solute concentration rather than on the type or identity of the solute particle. They include freezing point depression, lowering of vapor pressure, osmotic pressure, and boiling point elevation.

The boiling point elevation is the increase of the solvent's boiling point by the addition of the solute. Potassium chloride​ is a salt and a non-volatile solute that increases the boiling point of the solution.

The freezing point depression is one of the colligative properties that states the direct relationship between the molality and the freezing point of the solvent. As potassium chloride is a non-volatile solute it decreases the freezing point of the substance.

Therefore, the boiling point will increase but the freezing point will decrease after the addition of potassium chloride.

Learn more about colligative properties here:

https://brainly.com/question/1350420

#SPJ2

Find the number of moles of iron atoms obtain
from 320kg of iron (3) oxide​

Answers

Answer:

320 kg  of iron(III) oxide contain 4007.76 moles of iron atom.

Explanation:

Given data:

Mass of iron(III) oxide = 320 kg (320000 g)

Number of moles of iron atoms = ?

Solution:

First of all we will calculate the number of moles of iron(III) oxide.

Number of moles = mass/molar mass

Number of moles = 320000 g/ 159.69 g/mol

Number of moles = 2003.88 mol

1 mole of Fe₂O₃ contain 2 moles of iron atom.

2003.88 moles of  Fe₂O₃ contain,

2003.88 ×2 = 4007.76 moles of iron atom.

A student heats 25 mL of water from 20°C to 96°C in a glass beaker. The
model represents the motion of the water molecules during heating.
Explain why some of the water molecules shown in the model have
longer arrows than other water molecules during heating.

Answers

Answer:

Because the have acquired energy from the heating process, that is why the start moving faster.

Explanation:

Hello.

In this case, since the  initial liquid water molecules have a certain energy content, which makes them move with the relatively medium velocity characteristic in liquid-phase substances, once energy starts being added, it is evidenced that the molecules acquire more energy which is able to make them move faster.

In such a way, since the initial water molecules velocity is marked by a medium range arrows, meaning that the molecules are moving not-so-fast, not-so-slow but the heated  water molecules are marked by longer arrows, meaning that they move faster, we infer that such velocity increase is due to the addition of heat due to the heating process from 20 °C to 96 °C (just before boiling).

Regards!

Molecular motion is the action of motion of the molecules or the particles in a specific direction. The molecules start moving faster due to the energy given by the heat.

What are the factors affecting molecular motion?

The movement of the molecules or the particles in the system is affected by the temperature and the heat given to the system by the external source.

The initial molecules have relative speed and motion in the system and after the addition of the factors the energy of the motion of the particles gets affected.

When the temperature of the water in the beaker is increased then the average kinetic energy of the molecules also increases and hence the motion of the molecules increases.

The medium ranged arrows depict the average speed of the molecule movement in the medium, while the longer arrows suggest the fast-moving molecules of the water.

Therefore, the heat increases energy and in turn the molecular motion.

Learn more about molecular motion here:

https://brainly.com/question/14240663

Help pls:)?
If the low power objective has 10X printed on it, what would be the total magnification when looking through the microscope?

Answers

Answer:

The magnification of the microscope is equal to the magnification of the ocular lens times the magnification of the objective lens. Since the objective lens has 10x printed on them at "low power". The total magnification would be 10 times 10.

Explanation:

i hope this helps C:


Calculate the density of an
object with a mass of 58g and a
volume of 20 mL.
Enter

Answers

Answer:

D = 2.9 g/mL

Explanation:

Density = Mass over Volume

D = m/V

Step 1: Define

m = 58 g

V = 20 mL

D = unknown

Step 2: Substitute and Evaluate for Density

D = 58 g/20 mL

D = 2.9 g/mL

Water is composed of one atom of oxygen and two atoms of

Answers

Answer:

Hydrogen.

Explanation:

You've probably seen "[tex]H_{2}0[/tex]" which is the formula for water. It means that there's 2 hydrogen atoms, and one oxygen atom, in one molecule of water.

Hope this helps! Feel free to mark me Brainliest if you feel this helped. :)

Answer:

the answer is H. (hydrogen)

the density of a wooden block that has a volume of 5 cm3 & a mass of 30.5 g

Formula: ____________
Mass = ____
Volume = ____
Density = ____

Answers

Answer:

The answer is 6.10 g/cm³

Explanation:

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

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

From the question

mass = 30.5 g

volume = 5 cm³

We have

[tex]density = \frac{30.5}{5} \\ [/tex]

We have the final answer as

6.10 g/cm³

Hope this helps you

Acetylsalicylic acid (C9H8O4) is a monoprotic acid commonly known as aspirin. A typical aspirin tablet, however, contains only a small amount of the acid. In an experiment to determine its composition, an aspirin tablet was crushed and dissolved in water. It took 14.40 mL of 0.1466 M NaOH to neutralize the solution. Calculate the number of grains of aspirin in the tablet. (One grain = 0.0648 g and the molar mass of aspirin = 180.2 g/mol.)

Answers

Answer:

6 grains

Explanation:

The equation of the reaction between NaOH and aspirin is;

C9H8O4(aq) + NaOH (aq) ------>C9H7O4Na(aq) + H2O(l)

Amount of NaOH reacted = concentration × volume = 0.1466 M × 14.40/1000 L = 2.11 × 10^-3 moles

Given that aspirin and NaOH react in a mole ratio of 1:1 from the balanced reaction equation above, the number of moles of aspirin reacted is 2.11 × 10^-3 moles

Hence mass of aspirin reacted = 2.11 × 10^-3 moles × 180.2 g/mol = 0.38 g

If 1 grain = 0.0648 g

x grains = 0.38 g

x= 0.38 g/0.0648 g

x= 6 grains

The mass of 1 gram:

is kept as a standard platinum cylinder in France
equals 1 cm³
is .01 kg
equals the mass of 1 mL of water at 4°C

Answers

Answer:

C. equals the mass of 1 mL of water at 4°C

Explanation:

Scientists utilize models for a variety of different purposes, but each type of scientific model has limitations. What might
be a limitation of existing solar system models?
a. They are not based on experimentation.
b. They are used for prediction.
C. They cannot be changed.
d. They are based on current knowledge,
Please select the best answer from the choices provided
А
B
С
D

Answers

C. They cannot be changed.

I saw this on quizlet, hope this helps!

Answer:

D.They are based on current knowledge.

Explanation:

Guy above me is wrong

The specific heat of silver is 0.24 J/g•°C. How many joules of energy are needed to warm 4.37 g of silver from 25.0°C to 27.5°C?

A. 2.6 J

B. 46 J

C. 0.14 J

D. 0.022 J

Answers

The heat energy needed to change the temperature of  4.37 gram of silver sample of specific heat 0.24 J/ g °C from a temperature of 25 to 27.5 °C is 2.6 J.

What is calorimetry ?

Calorimetry is an analytical  technique used to determine the heat energy absorbed or released by  a system. The calorimetric equation relating the heat energy q with the mass of the substance m, specific heat c and temperature difference ΔT is given as:

q = m c ΔT.

Given that the mass of the sample of iron = 20 g

temperature difference   ΔT = 27.5 - 25 = 2.5 °C

specific heat c = 0.24J/ g °C.

The heat energy absorbed by the sample is calculated as follows:

q = 4.37 g ×  0.24 J/ g °C × 2.5 °C

 = 2.6 J.

Therefore, the heat energy required to the raise the temperature of the sample of iron is 2.6 J.

Find more on calorimetry :

brainly.com/question/11477213

#SPJ6

Read the statement below and decide if it represents physical change or chamical change.
Iron is heated, causing it to melt.
O Physical Change
Chemical Change

Answers

It is a physical change because the appearance is the only thing that changes.

The graph shows the average monthly rainfall for a
forested area.
In which month is a high alert for fire danger most
likely?

A. April
B. August
C. May
D. October

Answers

The answer is A. April

Answer:

The Answer would be A. April

Explanation:

Least amount of rainfall out of all the months we have to choose from.

Where is the north pole of the bar magnet, based on the magnetic field lines
shown?

Answers

Answer:On the Right End

Explanation: Trust me I just got it wrong on APEX to answer it for y’all On the right end is the correct answer

Answer:

Right end

Explanation:

Just did the quiz

The thermite reaction occurs when iron(III) oxide reacts with solid
aluminum. The reaction is so hot that molten iron forms as a product.
>
Fe2O3(s) + Al(s) → Fe(C) + Al2O3(s)
What mass of aluminum should be used in order to completely
consume 10.0 g Fe2O3(s)? If the reaction described produces 5.3 g
Al2O3(s), what is the percent yield?

Answers

Answer:

[tex]m_{Al}=3.38gAl[/tex]

[tex]Y=83.1\%[/tex]

Explanation:

Hello.

In this case, for the given balanced reaction:

[tex]Fe_2O_3(s) + 2Al(s)\rightarrow 2Fe(s) + Al_2O_3(s)[/tex]

For 10.0 g of iron (III) oxide (molar mass = 160 g/mol), based on the 1:2 mole ratio with Al (atomic mass = 27 g/mol), the required mass is then:

[tex]m_{Al}=10.0gFe_2O_3*\frac{1molFe_2O_3}{160gFe_2O_3} *\frac{2molAl}{1molFe_2O_3} *\frac{27gAl}{1molAl} \\\\m_{Al}=3.38gAl[/tex]

Moreover, as 5.3 g of aluminum oxide are actually yielded, from the 10.0 g of iron (III) oxide, we can compute the theoretical mass of aluminum oxide (molar mass = 102 g/mol) via their 1:1 mole ratio:

[tex]m_{Al_2O_3}=10.0gFe_2O_3*\frac{1molFe_2O_3}{160gFe_2O_3} *\frac{1molAl_2O_3}{1molFe_2O_3} *\frac{102gAl_2O_3}{1molAl_2O_3} \\\\m_{Al_2O_3}=6.38gAl_2O_3[/tex]

Thus, the percent yield (actual/theoretical*100%) turns out:

[tex]Y=\frac{5.3 g}{6.38 g}* 100\%\\\\Y=83.1\%[/tex]

Best regards.

Living things help contribute to the water cycle.
A. true
B.false

Answers

A. hahwjwkwjwbwnkwwk
Answer: A

Living things are apart of the cycle

What is the toto number of neutrons in an atom of 73 li

Answers

The 73 in Li means that there are 73 protons and neutrons in this atom. To find the number of neutrons, simply subtract the number of protons, which is equal to the atomic number (which is 3 in this case).

70 neutrons.

A cough syrup contains red dye #40, with a concentration of 4.68 x 10-3 M.a.If you dilute the cough syrup by adding 175 mL of water to a 250. mL sample of the cough syrup, what will be the final concentration?

How do I do this?

Answers

Answer:

[tex]M_2=2.75x10^{-3}M[/tex]

Explanation:

Hello.

In this case, since a dilution process is a process by which the concentration of a solution decreases due to the increase of volume by usually adding water, it is important to take into account that the moles remain unchanged:

[tex]n_1=n_2[/tex]

Whereas in terms of molarity (M=n/V) can be written as:

[tex]M_1V_1=M_2V_2[/tex]

In such a way, since the initial concentration is 4.68e-3 M and the volume of such solution is 250. mL, the final volume results from mixing 250 mL of this solution with 175 mL, that is, to a volume of 425 mL. Thus, the concentration turns out:

[tex]M_2=\frac{M_1V_1}{V_2} =\frac{4.68x10^{-3}M*250.mL}{425.mL} \\\\M_2=2.75x10^{-3}M[/tex]

Best regards.

If you dilute the cough syrup by adding 175 mL of water to a 250 mL sample of the cough syrup, the final concentration would be 0.00275 M

Using a simple dilution equation:

number of moles before dilution = number of moles after dilution

Recall that: number of moles = molarity x volume (MV)

Thus:

  M1V1 = M2V2

In this case, M1 = 4.68 x 10-3 M, M2 = ? V1 = 250 mL, and V2 = 425 mL

M2 = 4.68 x 10^-3 x 250/425

                  = 0.00275 M

                    = 0.00275 M

More on dilution principle can be found here: https://brainly.com/question/13844449

Ok here is the next one
I’m counting on you
Thanks.

Answers

food moves through the mouth by muscle movement

II. Pure magnesium metal is often found as ribbons and can easily burn in the presence of oxygen. When 3.86 g of magnesium ribbon burns with 155ml of oxygen at 1.0 atm and 275 K , a bright, white light and a white, powdery product is formed, magnesium oxide. How many grams of excess reactant remain?

Answers

Answer:

[tex]Excess=3.53g[/tex]

Explanation:

Hello,

In this case, the undergoing chemical reaction is:

[tex]2Mg(s)+O_2(g) \rightarrow 2MgO(s)[/tex]

Next, we identify the limiting reactant by computing the moles of magnesium oxide yielded by 3.86 g of magnesium and 155 mL of oxygen at the given conditions via their 2:1:2 mole ratios and the ideal gas equation:

[tex]n_{MnO}^{by \ Mg}=3.86gMg*\frac{1molMg}{24.3gMg}*\frac{2molMgO}{2molMg} =0.159molMgO\\\\n_{MnO}^{by \ O_2}=\frac{1atm*0.155L}{0.082\frac{atm*L}{molO_2*K}*275K} *\frac{2mol MgO}{1molO_2} =0.0137molMgO[/tex]

It means that the limiting reactant is the oxygen as it yields the smallest amount of magnesium oxide. Next, we compute the mass of magnesium consumed the oxygen only:

[tex]m_{Mg}^{consumed}=0.0137molMgO*\frac{2molMg}{2molMgO} *\frac{24.3gMg}{1molMg} =0.334gMg[/tex]

Thus, the mass in excess is:

[tex]Excess=3.86g-0.334g\\\\Excess=3.53g[/tex]

Regards!

Who would most likely be required to work with sodium hydroxide?

a plumber
a gardener
a bricklayer
a mechanic

Answers

Answer:

i think plumber

Sodium hydroxide is generally referred to as caustic soda used in soaps and cleaners. A plumber would most likely be required to work with sodium hydroxide. Hence, option A is correct.

What is the use of sodium hydroxide?

Soaps, paper, explosives, dyes, and petroleum are all made with sodium hydroxide. The presence of sodium hydroxide in a cleanser or a homemade aqueous solution converts these disconcerting fats into soaps, which are easily removed by water.

They have no odor and no color making them react with water and strong acids to produce salts. They are considered ionic compounds with sodium cation and chloride anion. They also are used in oxide coating and cleaning of metals.

Therefore, option A. plumber will most likely use sodium hydroxide.

Learn more about sodium hydroxide here:

https://brainly.com/question/20892971

#SPJ5

An empty graduated cylinder weighs 45.8772 g. After 20.0 mL of a liquid is added, the cylinder and its contents weigh 77.7572 g. What is the density of the liquid in g/mL?

Answers

Answer:

1.59g/mL

Explanation:

(777.7572 – 45.8772)g / (20.0) ml = (31.8800 g) / (20.0 ml) = 1.59 g/ml

3. Using the periodic table,
What is the average atomic mass of bromine?
What is the average atomic mass of magnesium?
How do your calculated answers in #1 and #2 compare to those on the periodic table?

Answers

Answer:

79.904 u for bromine

24.305 u

Not really sure what the 3rd question is asking

Explanation:

Pls help I am confused my sister got me sweating

Answers

Answer:

Im pretty sure its B. is released by salivary glands.

Explanation:

Other Questions
PLEASE HELP 30 POINTSBecause the rock is irregularly shaped, you used the displacement method to measure its volume.You used (______) to indirectly find the (_____) of the objects.Options for the 1st fill in the blank:- a balance- calculations- a graduated cylinderOptions for the 2nd fill in the blank: - density- mass- area QUESTION 14Read this sentence. It contains a comma splice.I want to go to the yard sale, I heard there are some great deals.Which of the following makes this sentence correct?O a. I want to go to the yard sale I heard there are some great deals.O b.I want to go to the yard sale but I heard there are some great deals.O c. I want to go to the yard sale; I heard there are some great deals.O d. I want to go to the yard sale and I heard there are some great deals. A Force Of 15 N Is Applied To A Spring, Causing It To Stretch 0.3 M. What Is The Spring Constant For The Particular Spring In the story the black cat. there are severaltypes of blindness on display in this story. Obviously, the two cats were partially blind, but the narrator also suffered from a sort of blindness. How so? What warning might Poe be trying to deliver to the audience in this story? Which Article in the Constitution establishes the Legislative Branch? While shopping for clothes, Curtis spent $78 less than 3 times what Daniel spent. Curtis spent $21. Write and solve an equation to find how much Daniel spent. Let x represent how much Daniel spent. Photography: Hurry please, Compare and contrast the film strip on which recording takes place as opposed to a digital storage device, such as a hard disk.Describe the process of transferring or converting a video from analog to digital format. help meeee!!!!!!!!!! 1. What does each Amendment say in simple terms? (Summarize each) MY 2ND TIMEE ASKING PLEASE HELP ILL GIVE U HOWEVER, MANY POINTS AS U DESIRE!according to the prisoners in the second selection, what restrictions were imposed on advocates who defend suspected heretics what would have been the implications of such restrictions Khara buys a shirt for $24 and 2 pair of pants. She doesn't remember the cost of the pants. She knows she spent a total of $102. Which equation would you use to find the cost of a pair of pants? graph WILL BE MARKED BRAINLIEST!!!!!!!!What is the equation of the line?i cant upload a file so im going to give the best description i can.A vertical line going through x (3,0) help please !need done before 11:59 una gaseosa *1 pointpara comerO para beber Read the excerpt from We Shall Not Be Moved.Everywhere in the garment district, by the front gates of little shops and big ones, picketers marched and sang. "O Dubinushka," they sang, and "Tortured and Enslaved," and other Russian folk and revolutionary airs. Icy rains poured down on them, some were in danger of frostbite a winter of record-breaking cold had already begun but there they were and there they stayed.The union men were amazed. "There never was anything like it," one ILGWU official declared. "An equal number of men never would hold together under what these girls are enduring.How would a careful rereading of this excerpt help a reader understand who made up the ILGWU?The reader could make a connection between the quote by one ILGWU official and the authors reference to union men just before it.The reader could make a connection between the quote by one ILGWU official and the reference to these girls in the same quote. The reader could make a connection between the quote by one ILGWU official and the authors description of other Russian folk in the first paragraph. The reader could make a connection between the quote by one ILGWU official and the descriptive phrase they sang in the first paragraph. Look at the map above. Which of the following statements is true?A.Cuba is located at number 1.B.Jamaica is located at number 3.C.Puerto Rico is located at number 2.D.The Lesser Antilles are located at number 4. Janice is unsure about her future career path she has grown up her and her family farm but she is also interested in medicine Janice becomes a member of the FFAN skills USA to try to learn more about the field and decide between them what would be more helpful to Janice You are a SpanishConquistador, you are sailingto the Americas on a ship.Write a journal entrydescribing what you hope tofind and what you hope to dowhen you get there. PLEASE HELP FAST write an inequality and solve it Mofor had some candy to give to his threechildren. He first took two pieces forhimself and then evenly divided the restamong his children. Each child receivedfour pieces. With how many pieces did hestart?