How many atoms are in 25.0 moles of calcium (Ca)?

Answers

Answer 1

Answer:

1.8066e+24 is the answer


Related Questions

Benzoic acid, HC6H5CO2,is a monoprotic acid(only one H+ ionizes)with a Ka=6.5×10^-5. Calculate [H+] and the pH of a .32M solution of benzoic acid. PLEASE ANSWER. ​

Answers

Answer:

[H⁺] = 4.56x10⁻³ M

pH = 2.34

Explanation:

Hello there!

In this case, according to the ionization reaction of benzoic acid:

[tex]HC_6H_5CO_2+H_2O\rightleftharpoons C_6H_5CO_2^++H_3O^+[/tex]

Whereas [tex][H_3O^+]=[H^+][/tex], we can set up the equilibrium expression in terms of [tex]x[/tex] (reaction extent) to obtain:

[tex]Ka=\frac{[C_6H_5CO_2^-][H_3O^+]}{[HC_6H_5CO_2]} \\\\6.5x10^{-5}=\frac{x^2}{0.32-x}[/tex]

However, since Ka<<<1, we can neglect the [tex]x[/tex] on bottom to easily solve for it:

[tex]6.5x10^{-5}=\frac{x^2}{0.32}\\\\x=\sqrt{6.5x10^{-5}*0.32} \\\\x=4.56x10^{-3}[/tex]

Which is actually the same as [H⁺]. Finally, the pH turns out to be:

[tex]pH=-log(4.56x10^{-3})\\\\pH=2.34[/tex]

Best regards!

WILL MARK BRAINLIEST FOR CORRECT ANSWER

Continue reading from Ruby Bridges’s autobiography.

We drove down North Galvez Street to the point where it crosses Alvar. I remember looking out of the car as we pulled up to the Frantz school. There were barricades and people shouting and policemen everywhere. I thought maybe it was Mardi Gras, the carnival that takes place in New Orleans every year. Mardi Gras was always noisy.

As we walked through the crowd, I didn’t see any faces. I guess that’s because I wasn’t very tall and I was surrounded by the marshals. People yelled and threw things. I could see the school building, and it looked bigger and nicer than my old school. When we climbed the high steps to the front door, there were policemen in uniforms at the top. The policemen at the door and the crowd behind us made me think this was an important place.

It must be college, I thought to myself.

–Through My Eyes,
Ruby Bridges

What evidence in the text supports the idea that Bridges did not realize the significance of her first day? Check all that apply.

“I remember looking out of the car as we pulled up to the Frantz school.”

“I thought maybe it was Mardi Gras.”

“As we walked through the crowd, I didn’t see any faces.”

“[The school] looked bigger and nicer than my old school.”

“The crowd behind us made me think this was an important place.”

“It must be college, I thought to myself.”

Answers

Answer: I remember looking out of the car as we pulled up to the Frantz school.”

“I thought maybe it was Mardi Gras.”

“As we walked through the crowd, I didn’t see any faces.”

“[The school] looked bigger and nicer than my old school.”

“The crowd behind us made me think this was an important place.”

“It must be college, I thought to myself.

Explanation:

“I thought maybe it was Mardi Gras.”

“[The school] looked bigger and nicer than my old school.”

“It must be college, I thought to myself.”

PLEASE HELP WITH CHEM !! Calculate the [OH-] of each of the following solutions given the [H+]. AND Classify each of the solutions in the question above as either acid, base, or neutral. AND FIND THE PH

Answers

pH, pOH, [H+], and [OH-] are all interrelated. For simplicity, we assume that we're working with aqueous solutions at 25 °C.

The following mathematical relations are relevant here:

pH = -log[H⁺]pOH = -log[OH⁻][H⁺] = 10^-pH[OH⁻] = 10^-pOHpH + pOH = 14[H⁺] × [OH⁻] = 10^-14

A pH of 7 is neutral; a pH less than 7 is acidic; and a pH greater than 7 is basic.

---

We are given four solutions of varying [H⁺], and we want to find the pH and the [OH⁻]. The pH will tell us whether the solution is neutral, an acid, or a base.

Finding the [OH⁻]

Using the relationship [H⁺] × [OH⁻] = 10^-14, we can calculate the [OH⁻] of each solution by dividing 10^-14 by the given [H⁺]:

[OH⁻] = 10^-14/(3.3 × 10^-5) = 3.0 × 10^-10

[OH⁻] = 10^-14/(4.0 × 10^-8) = 2.5 × 10^-7

[OH⁻] = 10^-14/(7.2 × 10^-11) = 1.4 × 10^-4

[OH⁻] = 10^-14/(8.2 × 10^-4) = 1.2 × 10^-11

Note: While not indicated here, the units for [H⁺] and [OH⁻] are moles/liter (M).

Finding the pH

To find the pH of each solution, we take the negative logarithm of the [H⁺] with base 10, i.e., pH = -log₁₀[H⁺]:

pH = -log(3.3 × 10^-5) = 4.48

pH = -log(4.0 × 10^-8) = 7.40

pH = -log(7.2 × 10^-11) = 10.14

pH = -log(8.2 × 10^-4) = 3.09

Note that, for significant figures involving logarithms, the number of decimal places should equal the number of significant figures in the argument of our logarithm (the argument is what we're taking the -log of). Since we're taking the -log of quantities given to two significant figures, our corresponding pH values are given to two decimal places.

Acid, Base, or Neutral?

As mentioned above, a pH = 7 is neutral, a pH < 7 is acidic, and a pH > 7 is basic.

4.48 < 7, so the first solution is an acid.

7.40 > 7, so the second solution is a base.

10.14 > 7, so the third solution is a base.

3.09 < 7, so the fourth solution is an acid.

Your opinion on chocolate

What is your opinion on chocolate, any kind like white chocolate dark, etc. also what do you think is the bad side of chocolate?

Answers

Answer:

Milk Chocolate

Explanation:

Some chocolates contain lots of sugar, but for Dark chocolate its healthy

Answer:

Milk chocolate the bad side of chocolate is getting fat

Explanation:

have u ever tried shreks snickers before?

How does the environment in which an organism lives determine which traits are adaptations?
can someone plss help me??​

Answers

Answer:

When an organism lives in a certain environment there is a process called natural selection. Natural selection ensures that the organisms of a species with the best traits suited for an environment will reproduce and pass on those traits to the offspring.

Explanation:

The theory of natural selection was studied by Charles Darwin in The Origin of Species by Means of Natural Selection if you need more information.

what is the limiting reactant of 20.0 moles of o2 react with 30.0 moles of h2 according to the following reaction ? 2H2 + O2 = 2H2O

Answers

Answer:

The limiting reactant is hydrogen.

Explanation:

According to the balanced equation for synthesis of water, hydrogen is used up twice as fast as oxygen -- we need two moles of H2 for every one mole of O2 when creating water.

Since we have 20 moles of oxygen, this means we would need twice as much hydrogen, or 40 moles, to use it all up. There is only 30 moles of hydrogen, which means that all the hydrogen will be used before the 20 moles of oxygen is used. Hydrogen limits production in this case.

We have that

From the Question we are told that

20.0 moles of o_2

30.0 moles of h_2

Therefore

The ratio  

For more information on this visit

Hannah made a diagram to show how plants make their own food. What should Hannah write to fill in the blank in the diagram?
A)
heat from the soil
B)
energy from the Sun
C)
heat from the roots
D)
energy from the wind
PLS SOME HELPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPP I NEED HELPPPPPPPPPPP

Answers

Answer:

Answer: Energy from the sun.

Explanation:

If you look at the hints it says that it needs something else for a plant to grow and what does a plant need?

Air, Water, and energy from the Sun to make food

Hope this helps :)

Answer:

Energy from the sun

Explanation:

What is the pH of an aqueous solution of HCl with a hydrogen ion
concentration of [H+] = 6.7 x 10-6 M? Round your answer to the nearest
hundredth.

Answers

Answer:

pH = 5.17

Explanation:

pH = -log[H+] = -log(6.7 x 10^-6) = 5.17

What element is found in water?

1. Carbohydrate

2. Carbon

3. oxygen

Answers

Explanation:

3. the element is oxygen

oxygen is in water! ;)

Which of these do NOT show malleability a) Iron
b) Sulfur
c) Copper
d) Aluminum​

Answers

Answer:Sulfur

Hope this helps!

Explanation:

Answer Is B) Sulfer !

El etanol combustiona con el oxigeno produciendo dióxido de carbono gaseoso y agua: En un proceso se hacen reaccionar 450.2 g de dioxígeno con 998. 2 g de etanol . a) ¿Cuál de los reactivos es el limitante? b) Calcule la masa de dióxido de carbono que se formará c) ¿ Cuanto del reactivo en exceso quedará sin reaccionar?

Answers

Answer:

uh oh stinky uh oh stinky

How are a rainforest and a desert different?

Answers

Answer:

Difference between Desert Plants and Rainforest Plants. The deserts are very dry land areas that can be hot or cold and experience very less rainfall. On the other hand, rainforests receive an enormous amount of rain. Both are homes to a variety of plants.

Explanation:

1. Cancer is a disease in which cells

a. grow and divide uncontrollably. b. die before they can mature.

c. stop producing DNA. d. die during mitosis.

____ 2. Which of these traits is controlled by a gene with multiple alleles?

a. straight hairline b. smile dimples

c. widow’s peak d. blood type

____ 3. Which of these is an example of the benefits of genetic engineering?

a. cross-breeding to create disease-resistant crops

b. creating human insulin to treat people with diabetes

c. analyzing karyotypes and pedigree charts

d. growing a new plant from a cutting

____ 4. A carrier is a person who has

a. one recessive and one dominant allele for a trait.

b. two recessive alleles for a trait.

c. two dominant alleles for a trait.

d. more than two alleles for a trait.

____ 5. Sex-linked genes are genes on

a. the X chromosome only. b. the Y chromosome only.

c. the X and Y chromosomes. d. all 23 pairs of chromosomes.

______ 6. What is the chromosome theory of inheritance?

a. Chromosomes are carried from parents to offspring on hybrids.

b. Genes are carried from parents to offspring on chromosomes.

c. Hybrid pairs of chromosomes combine to form offspring.

d. Codominant genes combine to form new hybrids.

____ 7. How can a mutation affecting skin be harmful to an animal?

a. It can make the animal more visible to its prey or predators.

b. It can cause disease in the animal.

c. It can make the animal resistant to certain diseases.

d. It can make the animal resistant to drugs

______ 8. What happens during meiosis?

a. Two sex cells combine.

b. Chromosome pairs separate and are distributed into new sex cells.

c. Each sex cell copies itself to form four new chromosomes.

d. Chromosome pairs remain together when new sex cells are formed.

Answers

Answer:

1. a

2. a.

3. b.

4. a.

5. c.

6. b.

7. a.

8. c.

Explanation:

I just need 4-8! Plz hurry!!!!!!!!!!!

Answers

Answer:

4: 90N

5: 7.77777m/s

6: 4

7: 12.5609756098

8: 187.5

Explanation:

Which region on the map has the highest risk of future landslides? a- Region 1 b-Region 2 c- Region 3 d- there is no way to make comparisons about the risk of future landslides? The subject is science (8th grade)

Answers

Answer:

Explanation:

Which region on the map has the lowest risk of future landslides?

Savvas Realize. Investigation 8 Experiment 1

Answers

Answer:

–1065.25 KJ of energy.

Explanation:

From the question given above, the following data were obtained:

4FeO + O₂ —> 2Fe₂O₃  ΔH = –560.66 kJ

From the balanced equation above,

The formation of 2 moles of Fe₂O₃ released –560.66 kJ of energy.

Finally, we shall determine the amount of heat energy released when 3.8 moles of Fe₂O₃ are produced. This can be obtained as follow:

From the balanced equation above,

The formation of 2 moles of Fe₂O₃ released –560.66 kJ of energy.

Therefore, the formation of 3.8 moles of Fe₂O₃ will release

= (3.8 × –560.66)/2 = –1065.25 KJ of energy.

Thus, –1065.25 KJ of energy is released from the reaction.

Because the triple beam balance is zeroed before it is put into use, it measures
A.
volume
B.
weight
C.
the effects of gravity
D.
mass

Answers

Answer b weight....
Hope this helps

describe each of the three states of matter (solid, liquid, gas)​

Answers

Explanation:

In a solid particles are firmly together and are stuck in a regular pattern

in a liquid particles still touch but arent in a fixed pattern

in a gas particles move quickly in all directions

Which statement is correct?
A. Physical changes produce new substances; chemical changes do not.
B. Chemical changes produce new substances; physical changes do not.
C. Both physical changes and chemical changes produce new substances.
D. Neither physical changes nor chemical changes produce new substances.

Answers

Answer:

B. Chemical changes produce new substances; physical changes do not.

Explanation:

Physical changes only alter appearances, while chemical changes are interactions that create new chemical formulas.

2. How many moles are in 2.8 Liters of CO2 gas?

Answers

Answer:

0.125 moles

Explanation:

2.8 litres is equivalent to 2.8dm³

At STP,

1 mole = 22.4 dm³

x mole = 2.8 dm³

Cross multiply

22.4x = 2.8

Divide both sides by 22.4

x = 2.8/22.4

x = 0.125

True or false?
A limitinh factor is an environmental factor that increases the growth of a population

True or false?
Biomes are characterized by temperature, precipitation, and the plant and animal communities that live there

Answers

The answers are :
1 - F
2- T
1 False
2 True

Good luck!!

What type of chemical reaction is demonstrated by this equation? A+BX-AX+B

Answers

Answer:

d an acid - base reaction.

Explanation:

Answer:

single replacement

Explanation:Look it up and got it from quizlet it should be right.

Waste water from nuclear power plants is generally ?

Answers

☁️ Answer ☁️

Waste water from nuclear power plants is generally: radioactive.

Hope it helps.

Have a nice day noona/hyung

Why should we work to protect estuaries? Select all that apply.
PLSSSS

Answers

Answer:

1, 3, and 4

Explanation:

I'm guessing, but those make the most sense

Answer:

3 and 4

Explanation:

balanced the equation please Fe + O2 → Fe2O3

Answers

Answer: The balanced equation is 4,3,2,  

Answer: Balanced equation = 4Fe + 3O2 => 2Fe2O3.

Explanation:

Aliyah found a tarnished silver dollar and recalled that tarnish results when metals react with oxygen or sulfur compounds in the air. She polished the silver dollar to remove the tarnish until it was shiny again. She also polished a copper bracelet and a gold ring. What physical property of these metals makes them shiny?

A. conductivity

B. ductility

C. luster

D. malleability

Answers

Answer:

C.

Explanation:

Luster

PLEASE PLEASE HELP THIS IS SCIENCE !!
ILL MARK U BRAINLIEST IF UR CORRECT

Answers

Answer:

Q 14 Deceleration

Explanation:

You are slowing down

Answer:

Explanation:

question 14 is a

question 15 is c

questoin 13 is d

What is the type of structure indicated below?
a- ionic structure
b-resonance structure
c- molecular structure
d-electron dot structure

Answers

Answer:

Electron dot structure

Explanation:

This is because electron dot structure is the structure that shows or indicate valence electrons of an atom and dots

is use around the element symbols . The number of dots shows the total number of valence electrons that are present in the atom of the molecules.

helllp meee pls . ....... ..... . . . . .
. . . . . . . . . .. . . . . ... .. . . . . ....... . . .. . . .. . . . . . . . . ... .. . . . ....

Answers

The answer is A “ mutations”

calcium phosphate consists of two ions chemically bonded together. What are charges of each ion?

Answers

Answer: Ca^2+ and P^3-

Explanation:

Other Questions
Following the Berlin Conference European nations created areas withinAfrica for each participating European country to colonize. What impact onAfrica do you think this might have in the 20th century?* Can someone please help? Mary is buying a case of water. She spends $7.99 for a case of 24 bottles. What is the unit rate? (Cost for 1 bottle) * An adaptation is:A) a physical characteristic that an organism develops during its life in response toenvironmental change.B) the Way that an organism acts when under high selective pressures.C) an inherited trait that helps an organism to survive and reproduce in its environment.D) a chemical change in the DNA of an organism that produces variation of genes. The function table below represents the linear function y = 4x 3. Which answer represents the outputs of the function table Which expression is equivalent to 2( 8v 4)+6v? (7^3)^3Simplify.Rewrite the expression in the form 7^n Question 8 of 47Which 20th-century Chinese leader led the Nationalist Party in its fightagainst communists during the Chinese Civil War?A. Sun Yat-senB. Chiang Kai-shekC. Mao ZedongD. Deng Xiaoping The graph shows a proportional relationship. Which equation matches the graph? Write the series using summation notation.-2 +4-8 + 16 - 32 Shepherd has gone for an interview at an engineering firm in Manhattan and has been asked to complete a self-report survey to help interviewers understand if he is the right candidate for the job. From the interview, they have found that he is introverted, empathic, scrupulous, and cooperative in nature, which are key characteristics needed for the job. These characteristics about Shepherd indicate his ________. Group of answer choices talent genealogy knowledge skill personality Which value is MEAN of the data set?A)480B)485500D)The MEAN cannot be determined from the available information. The bill for car repairs is $425 for parts and labor. The cost of parts is $226 and labor is $36.00 per hour. If h represents the number of hours of labor, which equation can you use to find the number of hours of labor?Group of answer choices226 = 425 36h226(h + 226) = 42536 + 226h = 42536h + 226 = 425 What are the independent and dependent variables in a circuit? PLEASE ANSWER!!!!!!!!!!!!!!!!!!!!!!!! Cam, Yusef, and Spencer have resolved to drink more water each day. The recommended amount of water per day is 64 ounces. a. Cam has 10% of the recommended amount of water left to drink before bed. How many ounces of water does she need to drink to reach her goal? Show your work and/or explain your reasoning. x/41=3What is the value of x? I need more help on the other chart pleaseCalculating pHsee chart below The statement Research is not a straight line means: The total bill for drinks and a pizza for three people is $14.90 before tax. The group wants to leave a 15% tip on the cost of the food, not including tax. What will be the amount of the tip?