# I don't have a clue where to start with this problem: Carbon has two stable isotopes, 12/6C and 13/6C, and fluorine has only one stable isotope, 19/9F. How many peaks would you observe in the mass spectrum of the positive

55,363 results
1. ## Science

1) Which of the following is true about photosynthesis? A. It is an exothermic reaction B.It is a endothermic reaction ***** C.It produces carbon dioxide D. It occurs in animals 2) Atomic Theory is A.Subject to change if new information is discovered B.A

2. ## Science Help!

Lisa studied the models of three carbon nuclei shown below. She listed information about the carbon nuclei in a table. Name Carbon 12 number of protons 6 number of neutrons 6. Name Carbon 13 number of protons 6 number of neutrons 7. Name Carbon 14 number

3. ## science

1. How do plants recycle carbon during photosynthesis?(1 point) The carbon in carbon gas is recycled as glucose.**** The carbon in glucose is recycled as carbon gas. The carbon in carbon dioxide is recycled as glucose. The carbon in glucose is recycled as

4. ## chemistry

Europium has two stable isotopes, 151 Eu (150.9198 u) and 153 Eu (152.9212 u). The atomic mass given for Eu is 151.9640 u. What is the percent abundance of 153 Eu ??

5. ## Chemistry

Which of the following statements about isotopes is/are true? a. Because isotopes have different numbers of neutrons, they have different mass numbers. b. because neutrons determine an atom's chemical properties, isotopes of the same element are very

6. ## Math(check)

1)Find the range of the relation [(-1,4)},(2,5),(3,5)}.Then determine whether the relation is a funtion. 4,5,5 is the range 4,5 is a function 2)Find f(-1),if f(x)= x^2-6x/x+2 (-1)^2-6(-1)/-1+2 1+6/-1+2 7/1 =7 3)Find f(a),if f(t)= 2t^2-t-2. 2(a)^2-a-2

7. ## Chemistry

Zinc has three major and two minor isotopes. For this problem, assume that the only isotopes of zinc are the major ones, zinc-64, zinc-66, and zinc-68. The atomic mass of zinc-64 is 63.9291 Da, that of zinc-66 is 65.9260 Da, and that of zinc-68 is 67.9248

8. ## chemistry

Gallium is a metal with a wide variety of uses. Some of its applications include computer memory chips, light emitting diodes and lasers. Radioactive isotopes of gallium are used to image the human body and locate tumors. Naturally occurring gallium

9. ## Physics

A ball of mass 0.15kg is dropped from rest at a height of 1.25m. it rebounds from the floor to reach a height of 0.960n. what impulse is given to the ball from the floor? i don't have a clue where to start. i know impulse is constant force x change in time

10. ## Physics

A beam of singly ionized carbon atoms (C-12, C-13, and C-14 isotopes) is injected into a mass spectrometer, which isotopes would follow the trajectory of greatest diameter and strike the detection plate furthest? I know the answer is C-14, but why? can

11. ## Chemistry

Which element has no stable isotopes? 1. (subscript)27 Co 2. (subscript)51 Sb 3. (subscript)90 Th 4. (subscript)82 Pb I believe it's either 2 or 3, but I can't decide which. I'm not sure how to go about answering this question, how can you tell which have

12. ## Calculus 2 (Differentiate & Decay Problem)

I have two problems I need help on, can someone show and explain step by step how to do the problems? For #1, how would you differentiate and solve the inital-value problem? For #2, I don't understand what I am doing wrong with the problem..I am sure it is

13. ## Chemistry

The decompostion of dinitrogen pentoxide has been studied in carbon tetrachloride (CCl4) at a certain temperature: 2N2O5→4NO2+O2 [N2O5] Inital rate (M/s) 0.92 ...... 0.95x10^-5 1.23 ...... 1.20x10^-5 1.79 ...... 1.93x10^-5 2.00 ...... 2.10x10^-5 2.21

14. ## physics

PLEASE HELP!! I HAVE A TEST TOMORROW!! if Q=30 uC, q=5.0 uC, and d=30cm, what is the magnitude of the electrostatic force on q in N? (Ke= 8.99 x 10^9 Nm^2/C^2) (uC= micro coulombs) (u= 10^-6) a. 15 b. 23 c. zero d. 7.5 e 38 i don't know where to start with

15. ## Mass Spectrometry

I don't have a clue where to start with this problem: Carbon has two stable isotopes, 12/6C and 13/6C, and fluorine has only one stable isotope, 19/9F. How many peaks would you observe in the mass spectrum of the positive ion of CF4+? Assume that the ion

16. ## Math

What is my number? clue 1. my number is a multiple of 2 and 7 clue 2. My number is less than 100 but larger than 50. clue 3. My number is the product of three primes, which are all different. Can some one tell me how to work this problem? Well, let's look

17. ## Earth Science (check answers)

1. The mass number of an atom is obtained by totaling the number of_____and____. a. electrons and protons b. electron and neutrons c.protons and neutrons d.neutrons and isotopes Is it B? 2. Which of the following statements about the chemical combinations

18. ## science

One way the modern atomic model differs from Thomson’s atomic model is that electrons are no longer scattered throughout an atom’s positive matter like chocolate chips in cookie dough. Instead, each electron is outside of the nucleus occupying a

19. ## physics

A sample of charcoal from an archaeological site contains 55 g of carbon and decays at a rate of .877 Bq. How old is it? ok I am totally lost, I don't know where to start

20. ## Chemistry

Copper is composed of two naturally occurring isotopes: Cu−63 (69.170%) and Cu−65. The ratio of the masses of the two isotopes is 1.0318.

21. ## Earth science

What is an example of a stable system? How were you able to determine whether or not this system is stable? Please don't attach files, my parents do not allow me to click on any attached files!

22. ## Ap Chemistry

one problem the researchers faced was an uncertainty about whether the signals observed in certain mass spectrometry data were, in fact, due to lead isotopes. Explain why this was a problem. In other words, why wasn't information about the mass of the

23. ## AP Chemistry

One way of separating oxygen isotopes is by gaseous diffusion of carbon monoxide. The gaseous diffusion process behaves like an effusion process. Calculate the relative rates of effusion of 12C16O, 12C17O, and 12C18O. Name some advantages and disadvantages

24. ## Chemistry

This Chem problem is really difficult -Need help please! Magnesium Consists of three naturally occuring isotopes. The percent abundance of these isotopes is as follows: 24Mg(78.70%), 25Mg(10.13%) and 26Mg(11.7%). The average atomic mass of the three

26. ## chemistry

(a) Consider the gaseous molecule BN-. At home, construct the molecular orbital diagram that is consistent with the known order of filling of molecular orbitals in the second period and with BN- being stable and paramagnetic. What is the bond order of BN-?

27. ## Sequences

Terms 1 through 5 of a sequence are shown below. 8/81 , 4/27 , 2/9 , 1/3 , 1/2 What is the 10th term in the sequence? I have no clue. I tried having common denominator of 81, but that just confused me more. I would try to show more work, but I really don't

28. ## chemistry

there are 3 naturally occurring stable isotopes of oxygen:O-16,O-17, O-18. there are 2 naturally occurring stable isotopes of hydrogen: H-1, H-2.how many different water molecules can be made using the various combination's of all the isotopes of hydrogen

12.0 g of carbon reacts with 32.0 g of oxygen to form 44.0 g of Co2. if we react 20.0 g of oxygen with 20.0 g of carbon,how many grams of carbon will be used up?..... i have no clue where to start... can u just tell me the steps to solve similar problems

30. ## Chemistry

Thinking about the uses of radioactive isotopes, which statement is true? A. The iodine isotope, I-27, is used to diagnose thyroid disorders. B. Radiation may be detected because it ionizes the atoms it affects. C. It’s clearly understood that

31. ## chemistry

carbon -12 and carbon -14 are the exact same atom isotopes of the same atom completely different atoms the same except that carbon -14 has 2 extra electrons

32. ## science

Which statement best explains why dating geologic materials from the Quarternary Period uses a different radioactive isotope than for materials from the cambrian Period? a. all rocks contain radioactive substances. b. some isotopes decay faster than

33. ## science

When carbon in the form of diamond is burned to produce CO2, more heat is given off than when carbon in the form of graphite is burned. What form of carbon is more stable under ordinary conditions? What bearing does this conclusion have on the origin of

34. ## algebra 2

PLEASE HELP wiTH ALL OF THEse. I DON'T KNOW WHERE TO START---THANKS! 1. At 2pm the number of bacteria in a colony was 100, by 4pm it was 4000. Write an exponential function to model the population y of bacteria x hours after 2pm. 2.Using the information in

35. ## Chemistry

Combustion of a 0.1595 g of menthol (156 g/mol) produces .449 g of Carbon Dioxide and 0.184 g of Water. What is the formula of menthol? I am really confused as to where to start. I converted the Carbon Dioxide and Water to moles and got .102 mol for both

36. ## physics 12

im stuck i have no clue where to start, please help me i just know the givens and some claculations. question: kevin stands on he top of a buiulding and he throws an aboject up into the air at a velocity of 16.0m/s at an angle of 25 degrees to the

37. ## English

State the meaning of the word expedite as it is used in the following sentence. Then, identify the context clue that you used to understand the meaning: definition clue, synonym, example clue, contrast clue, or inference clue. The majority of the elected

38. ## hw brain teaser help

here is what the teacher has. Kim, Rachel,Jim,and Rick finished first, second, third and fourth in a motor bike race. if there numbers were 5, 17, 1, 7, use the following clues to find out who had what # and what order they finished. * 17 said she would

39. ## biology

The answer to which of these scientific questions would MOST likely explain why all life on Earth is based on carbon? A. How many carbon isotopes are stable? B. How much carbon is found in Earth’s crust? C. What are the naturally occurring states of

40. ## Chemistry

Sorry for posting this again, I don't know if the question was skipped or not, but I was just wondering if I could get some help on this... thanks. There are 3 known isotopes of Hydrogen and 3 stable isotopes of oxygen. How many types of water molecules

41. ## Chem

There are two stable isotopes of Gallium Their masses are 68.92558 and 70.9247050 AMU. If the average atomic mass of gallium is 69.7231, what is the natural abundance of the lighter isotope? I don't know where to start!

42. ## Math

I have to find the value of X but I don't where to start I will show the problem below. X 2 - = - 5 400 I have no clue where to start please help! :(

43. ## Chemistry

There are 3 known isotopes of Hydrogen and 3 stable isotopes of oxygen. How many types of water molecules would these produce? Is it 3 ?

44. ## Physics

The following table gives values for the mass defect ∆m for four hypothetical nuclei: A, B, C, and D, isotopes of an element. ABCD Mass defect, ∆m(×10^-29 kg) A. B. C. D -6.0 -2.0 0 +6.0 Which statement is true regarding the stability of these nuclei?

45. ## Chemistry 11

12.0 g of carbon reacts with 32.0 g of oxygen to form 44.0 g of Co2. if we react 20.0 g of oxygen with 20.0 g of carbon,how many grams of carbon will be used up?..... i have no clue where to start... can u just tell me the steps to solve similar problems

46. ## physics

i need help understanding physics. im failing my class and don't want to do anything because i have zero clue where to start. im stuck on this problem currently. a cat pushes a ball from a 7.00 m high window, giving it a horizontal velocity of .20 m/s. how

47. ## science

list three differences between ions and isotopes? An ion is an atom that has at least one fewer electrons than it has protons. Thus, an ion always has positive charge. Hydrogen usually has one proton and one electron and has neutral charge. The hydrogen

48. ## Chemistry

Please help me solve this problem. I don't know how to approach this problem type. C3H8(g) + 5 O2 (g) ---- 3 CO2(g) + 4H2O(g) Conside the reaction. If you start with 7.0 moles of C3H8 (propane)and 7.0 moles O2, ________ mole(s) of carbon dioxide will be

49. ## chemistry

3. One problem the researchers faced was an uncertainty about whether the signals observed in certain mass spectrometry data were, in fact, due to lead isotopes. Explain why this was a problem. In other words, why wasn't information about the mass of the

50. ## Math

If y^5 + 3(x^2)(y^2) + 5x^4 = 49 , then dy/dx at the point (–1, 2) is? I have no clue how to start this problem, could someone explain it to me?

51. ## Chemistry

In a CH3CF2CHF2 molecule, which conformation is more stable and how much more is one stable than the other? I think Anti is more stable than gauche. I don't know why, I just think that a molecule is most stable in it's anti form.

52. ## chemistry

Carbon is able to form large numbers of organic compounds because carbon can A.form 4 bonds B.form single, double and triple bonds C.form chains, rings, spheres and sheets D.the carbon-carbon bond is very stable E.all answers are correct

53. ## Chemistry

I am supposed to find the percent abundancies of two isotopes. I am given the masses of both isotopes, along with the atomic mass. (This is a fictional element with only those two isotopes.) I am not given percentages for either isotope... how do I solve

54. ## Social Studies

Assignment: an essay about Rome's Three Heirs - Any ideas on how to start sorry don't have a clue help, anybody.

55. ## Science

Why does the relative atomic mass of chlotine is 35.5 ? thanx What is chlotine? Chlorine has isotopes with mass numbers ranging from 32 g mol−1 to 40 g mol−1. There are two principal stable isotopes, 35Cl (75.77%) and 37Cl (24.23%), found in the

56. ## English

I have a homework where I have to write about on this topic which says mythical character I admire and I don't have a clue on how to start Please help

57. ## Algebra

If a rectangular solid has a volume of x^3+2x^2+x, what could represent the lengths of the sides? don't have a clue how to start

58. ## English

I have a homework where i have to write a speech on this topic which says Mythical charector i admire and i don't have a clue on how to start please help

59. ## Chemistry

DrBob222 - can you set up the equation for the volume problem, i don't have a clue... Is this Charles Law? I know how to change C to K you add 273, but I don't know what figures go where in this formula PV=nRT......

60. ## Geology

Does this sound right? Describe your assigned method and how it is used to evaluate geologic time. My assigned method was Absolute Dating / Numerical Age. Absolute Dating / Numerical Age is the process that assigns a numerical age ( this tells how old a

61. ## CHEMISTRY HELP !!!!

Which of the following statements is/are CORRECT? 1. Naturally occurring isotopes account for only a small fraction of known radioactive isotopes. 2. A few radioactive isotopes with long half-lives, such as U-235 and U-238, are found in nature. 3. Trace

62. ## Chemistry

Why does CdCO3 have a significantly lower decomposition temperature than CaCO3, despite the similarity in the ionic radii of Ca2+ and Cd2+? I think they both decompose to give the metal oxide and carbon dioxide. Could the polarising ability of Ca compared

63. ## Astronomy

One possible energy source for the mysterious object you've just discovered is the fusion of hydrogen to form carbon-12 (the most common and stable isotope of Carbon). Hydrogen has an atomic mass of 1.00794 u, while carbon has an atomic mass of 12.010 u.

64. ## Math

Clara measured the diameter of the circle. How many centimeters is the diamter? Clue:The measure of the diameter is between 6 x 0.15 and 9 x 0.15. Clue:The units digit and the hundreths digit are the same Clue:If the diameter was 100 times longer, its

65. ## Chemistry

With isotopes, is it fair to say that each isotope has a slightly differnent volume due to the differing numbers of neutrons in the nucleus? i.e. carbon-12 is slightly smaller in volume than carbon-13. If not, why?

66. ## English

State the meaning of the word eradicate as it is used in the following sentence. Then, identify the context clue that you used to understand the meaning: definition clue, synonym, example clue, contrast clue, or inference clue.

67. ## Science

In a stable atom, the number of protons equals the number of___________ A. Nuclei B. Electrons C. Neutrons D. Isotopes

68. ## more chemistry this time concentration

Some of the problems. I honestly have no clue how to do these/where to look for answers. What is the concentration of 5.28*10^14 Carbon Tetrachloride molecules dissolved in 149 mL of water? How many grams of Carbon Dioxide will there be in a 16.43 mL of a

69. ## Chemistry

Can someone tell me if this makes any sense or if I need to start over. I am not sure if it even answers the question. Why is the benzene molecule represented as “a flat cyclohexane with a ring inside?” The benzene molecule is represented as “a flat

70. ## chem

Hi the following comes from my first homework assignment in AP Chemistry. I am totally lost on this question and don't know where to start. Thanks a lot in advance!!!!! A 0.1247 g sample of ascorbic acid, Vitamin C, was burned in a carbon-hydrogen

71. ## chem

how many grams of a precipitate will form when you mix 45 ml of a 3.5M silver nitrate solution with 45 ml of a 5.4 M magnesium chloride solution i sorted the problem but have no clue how to start

72. ## calculus

actually an ODE question(but there's no diff. eq. subforum) (y^2)(dy/dx)+y^3/x =2/x^2 using substitution u(x)=y^3 so I've been doing a few of these and getting them all wrong and this problem... I don't know where to start. I tried

73. ## English

State the meaning of the word eradicate as it is used in the following sentence. Then, identify the context clue that you used to understand the meaning: definition clue, synonym, example clue, contrast clue, or inference clue. Researchers continue their

74. ## Geometry

I don't know how to start this problem and it goes like this 6y2 = 7y - 5? Can you please help me just to start it off

75. ## Waves and optics

Find the binding energy per nucleon in J and eV for the three following isotopes, given their atomic masses in u: 22(A) 6(Z) of carbon 22.0572097 u

76. ## Chemistry

My question is why is benzene less reactive than 1,3,5-cyclohexatriene? I know that benzene does not undergo addition reactions and is extremely stable to oxidizing reagents. C atoms in benzene are connected by delocalized double bonds which make them

77. ## Chemistry

My question is why is benzene less reactive than 1,3,5-cyclohexatriene? I know that benzene does not undergo addition reactions and is extremely stable to oxidizing reagents. C atoms in benzene are connected by delocalized double bonds which make them

78. ## chemistry

Europium has two stable isotopes, 151 Eu (150.9198 u) and 153 Eu (152.9212 u). The atomic mass given for Eu is 151.9640 u. What is the percent abundance of 153 Eu ??

79. ## physics

In a gas at standard temperature and pressure, what is the length of the side of a cube that contains a number of molecules equal to the population of the earth (about 6 million people at present)? I know STP is 1 atm and 273K, but I have no clue how to

80. ## Chemistry

There was this problem on a test that I took recently. But, I never learned how to solve this. The problem was: it gave the mass of a certain compound and stated that it had 92% carbon. then it asked for the theortical yield of Carbon.

81. ## Algebra

I don't even know where to start with this problem... i'm supposed to simplify it but i don't get how, please help! 12e^x / e^4x I would really appreciate the help, thank you!

82. ## Physics

A sample of charcoal from an archaeological site contains 55 g of carbon and decays at a rate of .877 Bq. How old is it? ok I am totally lost, I don't know where to start

83. ## Chemistry

My question is why is benzene less reactive than 1,3,5-cyclohexatriene? I cannot find anything on 1,3,5 cyclohexatriene and why it is more reactive. I know that benzene does not undergo addition reactions and is extremely stable to oxidizing reagents. C

84. ## Physics

this question came up in my work, and i don't remember reading about it in my book. can you tell me what it is asking for, and how to do it.. if the change in position delta x is related to velocity v(with units of m/s) in the equation delta x=Av, the

85. ## chemistry

Look in the owner’s manual of your car to determine the amount of gasoline your tank can hold. Using the information presented in the text, calculate how much carbon dioxide is produced from driving your car for a year assuming that all the gas is octane

86. ## Chemistry

What is the famous isotope used in archeological dating? carbon 12 I thought it was carbon 14 yes carbon 14-- made an error But if you knew, why are you asking these questions? I need reaasurance, so when I have a test I know the exact answer C-14 is ONE

87. ## statistics

On a entrance exam, the mean was 50 and standard deviation was 5. If Ricky's z-score was -1.5, what was his exam score? I don't have a clue how to start to answer this question...

88. ## math

the sex of to domain species is unknown but they each have a probability of X and -5 what does x equal and what is the domain species? Please someone help me don't give me the answer just please explain the process of this to me i have no clue where to

89. ## Chemistry

An unknown element Q has two known isotopes: 60Q and 63Q. If the average atomic mass is 62.0 amu, what are the relative percentages of the isotopes?

90. ## Chemistry

An unknown element Q has two known isotopes: 60Q and 63Q. If the average atomic mass is 60.5 amu, what are the relative percentages of the isotopes?

91. ## Chemistry

An unknown element Q has two known isotopes: 61Q and 62Q. If the average atomic mass is 61.4 amu, what are the relative percentages of the isotopes?

92. ## Chemistry

An unknown element Q has two known isotopes: 60Q and 63Q. If the average atomic mass is 60.5 amu, what are the relative percentages of the isotopes?

93. ## Chemistry - Chemical Equilibrium

In a solution with carbon tetrachloride as the solvent, the compound VCl4 undergoes dimerization: 2VCl4 V2Cl8 When 6.6834 g VCl4 is dissolved in 100.0 g of carbon tetrachloride, the freezing point is lowered by 5.97*C/ Calculate the value of the

94. ## physics

two parallel conductors are located one above the other, with both carrying currents in opposite directions. As a result they repel each other. is the upper conductor in a stable state of levitation? b) Now we reverse one current so that the two conductors

95. ## science (chem)

I have a problem drawing this formula. CH3CH2CH2CH(CH3)CCCH3 The problem is the 2 c's next to each other. I don't know what that's supposed to look like since if it's 1 CH like with the bracketed CH3 it would be connected to that C but I'm confused as to

96. ## Chemistry

To clarify, a triple bond between carbon and oxygen is more stable than a triple bond between carbon and nitrogen because oxygen is more electronegative. Is my understanding correct?

97. ## science/physics

James combines the force of a tennis racket and his arm on a tennis ball. I don't understand what this question is asking, and it doesn't go with any other problem, could someone try to tell what it is asking because I have no clue ;-;

98. ## Algebra 1

I don't know where to start this problem off with... (-x^3) (-x)

99. ## Algebra

Help please (x^3 + 3x^2 - 2x+7)/(x+1)=11 I don't how how to solve this at all-the answer should be 11 but I don't have a clue how to get it-please show me this one so I can hopefully do my homeowrk-we did this in class today but I don't understand it

100. ## Grammar,English

I wwas told to write a 3 syllable word for each clue. The first letter is provided. 1.Rational or reasonable [Clue:L} 2.To stand for or symbolise {clue:R]