Wednesday
May 4, 2016

# Posts by Timofey

Total # Posts: 42

College Level Calculus
Each orange tree grown in California produces 720 oranges per year if not more than 20 trees are planted per acre. For each additional tree planted per acre, the yield per tree decreases by 15 oranges. How many trees per acre should be planted to obtain the greatest number of ...
November 12, 2013

Chemistry HELP!!
Estimate the difference in energy produced when we burn 1kg of carbon vs producing nuclear energy from 1kg of U-235. C + O2(g) -> CO2(g)
June 7, 2013

Chemistry - DrBob222
When sodium burns in air it produces a bright white light and heat energy 2Na + O2 2Na2O ?H = -414kJ/mol What would you expect to be the heat energy associated with the reverse process 2Na2O 2Na + O2 Can you please show the entire calculation with units please? This is what I ...
June 5, 2013

Chemistry
When sodium burns in air it produces a bright white light and heat energy 2Na + O2 2Na2O ?H = -414kJ/mol What would you expect to be the heat energy associated with the reverse process 2Na2O 2Na + O2 Can you please show the entire calculation with units please? This is what I ...
June 5, 2013

chemistry
June 2, 2013

chemistry
In graphite, the C-C bonds in the planes are very strong, but the force between the different planes is quite weak, and they can slip over one another. This explains the "soft" feel of graphite, and the fact that it is used as a lubricant, for example in motor oil. ...
June 2, 2013

Chemistry DrBob222
5. What volume would 27g of neon at 2 atm pressure and 50°C occupy? I have solved the problem correctly, but I am not sure if I have the correct units on this conversion so that everything will cancel out. Also, is it right to have 20g Ne/1mole K? I seem to be missing ...
May 29, 2013

Biologyyy
The Global Issue of Hepatitis C Hepatitis C Virus Infection Hepatitis C and its Prevention Nursing and Hepatitis C A Sexually Transmitted Disease: Hepatitis C Characteristics of Hepatitis C Hepatitis C: Diagnosis and Treatment Hope this Helps!
May 27, 2013

Chemistry--DrBob222
Estimate the number of moles of gas (and mass of gas assuming that it is all N2) inside your family car (or a friends if you don't have one). If the amount of gas was compressed at constant temperature to fit inside a coke can what ould the pressure inside the coke can be...
May 27, 2013

Chemistry
If 10g of NO react with 20g of O2, what is the maximum amount of NO2 that can be produced? My answer is Mol NO = 10/30 = 0.333 mols Mol O2 = 20/32 = 0.625 mols To react all the O2 you would need 2 NO*0.625 moles of NO/1mole O2 =1.25 O2? but, we just have 0.333 mols, so NO is ...
May 25, 2013

Chemistry
Calculate the volume occupied by 200g of steam at 200 °C and 0.5 atm. is my answer correct: PV = nRT V = nRT/P V = gRT/mm P V = (200g H2O)(0.0821 liters atm/1mole K)(473 K)/ (18g H2O/1mole )(0.5 liters atm) = 863 liters
May 24, 2013

Chemistry -- DrBob222
A gas initially at STP is heated to 50°C keeping the volume constant. What is its new pressure? I used this formula: P1 = 1 atm T1 = 273 K T2 = 323 K solve for P2 P2 = P1 (T2/T1) But, where do I use the 50 degrees C? Also, is my answer correct: P2 = 1atm x 323K/273K = 1.18...
May 24, 2013

Chemistry
What happens if you add more solute to a saturated solution?
May 22, 2013

english
Submissive - inclined or ready to submit ; unresistingly or humbly obedient Makes more sense than 'responsive' in the sentence above. Using submissive, gives the sentence better structure and its adequate word choice.
May 22, 2013

Chemistry
I will do that, thanks for your help once again DrBob222.
May 22, 2013

Chemistry
I guess so, thanks "K"
May 22, 2013

Chemistry---DrBob222
Am i solving this correctly, according to my answer/posts above??
May 22, 2013

Chemistry--Help!!
This was my answer, but it was wrong: 2NO + O2 ----> 2NO2 Molar Mass NO2 = 46g/mol Molar mass NO = 30g/mol Molar Mass O2 = 32g/mol 0.333 mols NO x 46g NO2/1mol NO = 15.3g NO2 mols NO = 10g NO/30g/1mol NO = 0.333 mols NO mols O2 = 20g O2/32g O2/1mol O2 = 0.625 mols O2 Where ...
May 22, 2013

Chemistry
If 10g of NO react with 20g of O2, what is the maximum amount of NO2 that can be produced? How do I know exactly which is limiting and which is excess, is there a calculation that shows this?
May 22, 2013

Chemistry
If 10g of NO react with 20g of O2, what is the maximum amount of NO2 that can be produced?
May 22, 2013

Chemistry
What is the mass of a sample of acetylene gas (C2H2)that contains 4.44 x 1034 atoms of carbon? Also, Im not sure how to convert from moles of C to moles of C2H2.
May 22, 2013

Chemistry--Help??
How do i illustrate the Fluorine correctly in relation to the conversion factors??
May 21, 2013

Chemistry
This is what I have, but teacher said I am showing the fluorine wrong somehow: F2 + 2NaBr ---> 2NaF + Br2 Moles NaBr = 100g NaBr/102.8938g NaBr/ 1mole NaBr =0.972 moles NaBr Moles F2 needed = 0.972 moles NaBr/2 molecules F/1mole NaBr =0.486 moles F2 mass F2 = 0.486 moles ...
May 21, 2013

Chemistry
Thnx, DrBob for that last answer to my question btw
May 21, 2013

Chemistry
How many grams of fluorine are required to react with 100g of NaBr in the following reaction: F2 + 2NaBr --> 2NaF + Br2 Also, does this show 1 F2 molecule or 2 F2 molecules and how will i write it with the conversion factors with units?
May 21, 2013

Easy Chemistry
is 2 molecules of fluorine the same as 2 fluorine molecules? if so then how/why
May 21, 2013

Chemistry
how many outer shell electrons does a carbon atom have using periodic table?
May 18, 2013

Easy chemistry
Whats the charge on a carbon cation?? I believe it is a positive charge, but does it have a number along with it?? not sure..
May 17, 2013

Chemistry Help
How many moles of ammonia are produced when 2.5 moles of nitrogen are reacted with hydrogen?
May 3, 2013

AP Chemistry Help!!
How many moles of P4O10 are produced when we react 8 moles of phosphorous with oxygen? I know the answer is: 4 mol P produces 1 mol P4O10 8 mol P produces 2 mol P4O10. Or, 1 mol P4O10 x (8 mol P / 4 mol P) = 2 mol P4O10. but, what is the balanced equation?
May 3, 2013

Chemistry
How many moles of P4O10 are produced when we react 8 moles of phosphorous with oxygen? I know the answer is: 4 mol P produces 1 mol P4O10 8 mol P produces 2 mol P4O10. Or, 1 mol P4O10 x (8 mol P / 4 mol P) = 2 mol P4O10. but, what is the balanced equation?
May 3, 2013

Chemistry Help
How many moles of butane do we need to produce 10 moles of CO2 by reaction with oxygen? I think the balanced equation is 2 C4H10 + 13 O2 -----> 8 CO2 + 10 H2O
April 30, 2013

AP Chemistry
How many moles of butane do we need to produce 10 moles of CO2 by reaction with oxygen? I think the balanced equation is 2 C4H10 + 13 O2 -----> 8 CO2 + 10 H2O
April 30, 2013

Chemistry
Write a balanced chemical equation for the combustion of trioleylglycerol. The molecular formula is C57H110O6.
January 22, 2013

AP Chemistry
Write a balanced chemical equation for the combustion of trioleylglycerol. molecular formula C57H110O6
January 22, 2013

AP Chemistry
how much heat is produced when the body metabolizes a gram of trioleylglycerol? I know that the combustion of triolelglycerol is exothermic with an enthalphy change of 9 calories per gram of trioleylglycerol molecules, so the combustion will release heat to the surroundings. I...
January 21, 2013

Calculus
A club has 45 members and its membership committee has 7 members. How many different membership committees are possible? I keep getting 1.6336632e10, but I know its not right somehow
August 19, 2012

Calc
I have sum of 2731 is correct?
August 17, 2012

Calc
How do i find the sum?
August 17, 2012

Calc
Find the sum of the terms of the finite geometric sequence 1, -2, 4, -8, ...,-8192.
August 17, 2012

Calculus
Prove via Mathematical Induction that (7*n) - 1 is divisible by 6. I have that it is divisble when n=1, but not n=2 and so on. How should I write the inductive proofs?
August 11, 2012

Calculus
Use mathematical induction to prove that the statement holds for all positive integers. Also, label the basis, hypothesis, and induction step. 1 + 5 + 9 + … + (4n -3)= n(2n-1)
August 10, 2012

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