Wednesday
September 28, 2016

Homework Help: Science: Chemistry

Recent Homework Questions About Chemistry

chemistry
what chemical changes are responsible for the color changes in the red cabbage lab?
Friday, March 4, 2016 by lulu

Chemistry
Determine the rate law, including the values of the orders and rate law constant, for the following reaction using the experimental data provided. Q + X yields products Trial [Q] [X] Rate 1 0.12 M 0.10 M 1.5 × 10-3 M/min 2 0.24 M 0.10 M 3.0 × 10-3 M/min 3 0.12 M 0....
Friday, March 4, 2016 by nan

Chemistry
A match must be struck against an object to produce a spark to start the burning process. Once the match starts burning, it releases a large amount of energy. Describe, in detail, what the potential energy diagram would look like for the burning of a match, and explain how ...
Friday, March 4, 2016 by nan

Chemistry
How does the potential energy of the reactants compare to the potential energy of the products in an exothermic reaction, and where does the energy that is given off come from? Explain your answer in complete sentences.
Friday, March 4, 2016 by nan

Chemistry
Which reaction did you perform in the hands-on activity? Describe the chemical combination that you investigated. Also describe any observations from the investigation, including the temperature change of the container.
Friday, March 4, 2016 by nan

Chemistry
Ascorbic acid is a compound containing of three element C,H, and O when a 0.214g sample is burned in oxyzen 0.320g of CO2 and 0.0874g H2O are formed. What is the Empirical formula of ascorbic acid?
Thursday, March 3, 2016 by Asifur

chemistry
2.) If the volume of a gas at -73 degrees celcius is doubled while pressure is held constant, what will be its final temperature in degrees celsius? 5.) A gas storage tank at a large industrial plant is designed to provide fuel under constant pressure. When the plant is shut ...
Thursday, March 3, 2016 by Zoey

chemistry
what mass of CdS is produced if 4.55g of cadmium reacts with 2.00g of sulfur?
Thursday, March 3, 2016 by tim

Chemistry
Write an overall balanced equation for these unbalanced half-reactions: In --> In3+ Cd2+ --> Cd I multiplied both sides by integers to get the electrons to be equal on both sides but I don't know what the final overall balanced equation looks like.
Thursday, March 3, 2016 by Blake

Chemistry
Mole calculations: How much does 2.5 x 10^24 molecules of p2o3 weigh ?
Thursday, March 3, 2016 by Aria

chemistry
How many kilojoules are required to melt 15g of ice at 0 degree celsius, and raise the temperature of the liquid that forms to 85 degree celsius?
Thursday, March 3, 2016 by Kate

chemistry
the reaction A+3B—>2C+D is first order with respect to reactant A and second order with respect to reactant B if the concentration of A is doubled and the concentration of B is halved the rate of the reaction would---------------by a factor of-----------
Thursday, March 3, 2016 by ruth

chemistry
the reaction A+3B->2C+D is first order with respect to reactant A and second order with respect to reactant B if the concentration of A is doubled the concentration of B is halfed and the rate of the reaction would -------by a factor of --------
Thursday, March 3, 2016 by ruth

chemistry
the reaction A+3B->2C+D is first order with respect to reactant A and second order with respect to reactant B if the concentration of A is doubled the concentration of B is halfed and the rate of the reaction would -------by a factor of --------
Thursday, March 3, 2016 by ruth

Chemistry
A 3.50L balloon contains 0.178 mol of gas. If 0.094 mol of gas is added to the balloon, what will be the new volume?
Wednesday, March 2, 2016 by Bill

Chemistry
What is the unit for molality? The unit for molality is moles per kg Or M/kg
Wednesday, March 2, 2016 by Angelina

Chemistry
4.5 moles of oxygen reacting with enough sodium will form how many moles of sodium oxide? How do you solve?
Wednesday, March 2, 2016 by Mac

Chemistry
If you have 14.2 mol of C4H10 and 85.6 mol of O2, which is the limiting reagent? I calculated mass using m=N*M, giving me the answer that C4H10 is the limiting reagent. That being said, the answer on the back says O2.
Wednesday, March 2, 2016 by AlphaPrimes

Chemistry
When the sugar glucose, C6H12O6 is burned in air, carbon dioxide and water vapor are produced. Write the balanced chemical equation for this process, and calculate the theoretical yield of carbon dioxide when 1.00 g of glucose is burned completely.
Wednesday, March 2, 2016 by Kaili

Chemistry
24.0 mL of 2.4 M silver nitrate is mixed with 32.0 mL of 2.0 M sodium chloride. ( I wrote the balanced equation as AgNo3+NaCl -> NaNo3 + AgCl ) A) Identify the precipitate formed by name and formula. - I wrote AgCl (silver chloride) B) Calculate the mass of precipitate ...
Wednesday, March 2, 2016 by Sara

Chemistry
3. suppose a gas at STP. Calculate its pressure at 25 degrees celcius if volume remains unchanged 5. suppose 1.11 L of an unknown gas in a rigid container constant volume is cooled from 22 deg. C to -55 deg C. Calculate the new pressure of the gas 6.) Suppose a 50.0 cm ^3 ...
Wednesday, March 2, 2016 by Dina

Chemistry
If a 20mL sample of milk has a 0.027M concentration of lactic acid, what would the pH be? what would the concentration and pH be in one litre?
Wednesday, March 2, 2016 by Hally

Chemistry
Hydrogen sulfide gas burns in the presence of oxygen to produce sulfur dioxide gas and water vapor. Write a balanced chemical equation, including the physical state
Wednesday, March 2, 2016 by Jasmine

11th grade chemistry
The bottled butane gas is installed in an oven that can supply 0.125 g/hr .In a kitchen room of volume 32 m^3 (volume of air), the oven is made to operate for 2 hours. Assuming the kitchen room is closed, what is the mole composition of the atmosphere in the kitchen when ...
Wednesday, March 2, 2016 by angy

Chemistry
What set of hybrid orbitals is used by Xe in XeO3F2? dsp2 d2sp3 sp3 dsp3 d2sp
Wednesday, March 2, 2016 by Dave

Chemistry
How many millimoles of HCl (aq) are neutralized by 0.35 g of CaCO3 (sol)? mmol
Wednesday, March 2, 2016 by Karen

Chemistry
If a 20mL sample of milk has a 0.027M concentration of lactic acid, what would the pH be? what would the concentration and pH be in one litre?
Wednesday, March 2, 2016 by Hally

Chemistry
N = Sp.gr*1000* percent% / eq.wt Prepare 200 ml of 5 N H2SO4 solution from concentrated H2SO4 , if we know that Sp.gr = 1.84 g/ml , percent = 98% , At.wt for (H= 1 , S=32 , O =16 ) Thank you a lot
Wednesday, March 2, 2016 by MAD

chemistry
Please I need a detailed explanation, am stuck doing this assignment, at what temperature in kelvin will co2 molecules have an rms speed equal to hydrogen at 20 Celsius?
Wednesday, March 2, 2016 by Emmanuel

Chemistry
Write the oxidation half reaction for Magnesium metal and write the reduction half equation for Cu^2+ ions? I don't understand, please give me a simple explanation.
Tuesday, March 1, 2016 by Stacy

Chemistry
Some hydrogen is collected over water at 10 degrees C and 105.5 kPa pressure. The total volume of the sample was 1.93 L. Calculate the volume of the hydrogen or reacted to STP.
Tuesday, March 1, 2016 by Charlie

Chemistry
Calculate the amount of heat energy transferred in the following situations: the temperature of 1.0g water rises from 22.5 degrees C to 24.5 degrees C. Feel like I am missing givens. Help! There are a few more like this but I just need to know how to set it up.
Tuesday, March 1, 2016 by Ryan

Chemistry lab
Discuss three unavoidable sources of error in Part 1 (the synthesis of the crystals) of this experiment and identify the major factors that would explain a less- than-100% yield. Note: human error is not an acceptable answer. Was the alum not dry enough for impurities to give ...
Tuesday, March 1, 2016 by Jake

Chemistry
How many mL of 0.101 M HCL are needed to neutralize 1.00 g of potassium hydroxide?
Tuesday, March 1, 2016 by Jennifer

chemistry
Calculate the percent ionization of a .31 molar solution of acetic acid. The ionization constant of acetic acid is 1.8 x 10^-5
Tuesday, March 1, 2016 by Avery

Organic Chemistry
We used sodium dichromate in sulfuric acid to oxidize borneol to camphor. Suppose you needed to prepare benzaldehyde from benzyl alcohol. Would the sodium dichromate be the best choice for this oxidation or are there better choices? Explain.
Tuesday, March 1, 2016 by Alyssa

chemistry
The three substances that can reduce Ag+ to Ag, but will not reduce Sn2+ to Sn are Zn Pb H2 Mg Cu I2 Al Ca
Tuesday, March 1, 2016 by Taylor

Chemistry
Show the calculation for the limiting reagent when 0.853g of sodium sulfate (95% pure) react with 1.707g of barium hydroxide octahydrate (87% pure) to produce a precipitate of barium sulfate. I've determined the equation is Na2SO4+Ba(OH)2*8H2O=BaSO4+2NaOH However, that is ...
Tuesday, March 1, 2016 by Kevin

Chemistry
If 258 mL of 2 molar HCl solution is added to 342 mL of 4.3 molar Ba(OH)2 solution, what will be the molarity of BaCl2 in the resulting solution? Answer in units of M.
Tuesday, March 1, 2016 by Avery

Chemistry
A 69 mL sample of a solution of sulfuric acid is neutralized by 41 mL of a .161 M sodium hydroxide solution. Calculate the molarity of the sulfuric acid solution. Answer in units of mol/L.
Tuesday, March 1, 2016 by Avery

chemistry
3.05 g of hydrated copper sulphate produces 1.94g of anhydrous salt.assuming complete removal of all water of crystallization,determine the formula of hydrated copper sulfate
Tuesday, March 1, 2016 by maria

Chemistry
When an aqueous solution of sodium hydroxide, NaOH, is added to an aqueous solution of chromium(III) nitrate, Cr(NO3)3, a precipitate of chromium(III) hydroxide, Cr(OH)3, forms. Write a balanced net ionic equation for this reaction.
Tuesday, March 1, 2016 by Tina

Chemistry
How is 4FeS2 + 11O2 = 2Fe2O3 +8SO2 a single replacement reaction?
Tuesday, March 1, 2016 by Gary

Chemistry
A 0.10M solution of a certain monoprotic weak acid has a pH of 2.44. Calculate Ka.
Tuesday, March 1, 2016 by Jackson

Chemistry (stoichiometry)
22 moles of benzene are completely reacted with molecular oxygen, how many moles of carbon dioxide will be produced? and if 150 grams of water were produced, how many moles of oxygen must have reacted
Tuesday, March 1, 2016 by Alex

Chemistry- Dr.Bob
What is the final temperature and physical state of water when 250 grams of water at 85 degrees C is added to 80.0 grams of ice at -15 degree C? Is the physical state of water liquid? The explanation from bobpursly was this The sum of heats gained =0 80(cice)(0+15)+80Hf+80cw(...
Tuesday, March 1, 2016 by Student

Chemistry-Dr.Bob 222
What is the final temperature and physical state of water when 250 grams of water at 85 degrees C is added to 80.0 grams of ice at -15 degree C? Is the physical state of water liquid? I still don't understand how to do this.
Tuesday, March 1, 2016 by Student

Chemistry
Please sir solve this... 6.3 gm of oxalic acid (eq. Wt.=63) is dissolved in 500 ml solution what will be the normality of the solution?
Tuesday, March 1, 2016 by Pradeep

Chemistry
I was given a list of 14 different solutions, and My homework question asks which of the solutions exhibit the common-ion effect and which ones are buffers? But, how would I be able to tell???
Monday, February 29, 2016 by CeCe

Chemistry (Food)
Which of the following are B vitamins? Check ALL that apply. A). ascorbic acid B). retinol C). calciferol D). thiamine E). niacin
Monday, February 29, 2016 by Dominick

Chemistry
In the voltaic cell that is represented as: Cu | Cu2+ || Fe | Fe2+. The only anion in solution in the cells and salt bridge is the nitrate ion. The directions the electron external circuit and NO3- flow in the salt bridge circuit will be: *electron flow is Fe to Cu *electron ...
Monday, February 29, 2016 by Mikah

Chemistry
The three substances that can reduce Ag+ to Ag, but will not reduce Sn2+ to Sn are Zn, Pb, H2, Mg, Cu, I2, Al, Ca
Monday, February 29, 2016 by Taylor

Chemistry (Food)
The average energy yield per gram of carbohydrate and of fat is A).4 kcal and 9 kcal, respectively B).9 kcal and 4 kcal, respectively C).9 kcal each D).4 kcal each
Monday, February 29, 2016 by Dominick

Chemistry
what type of reaction occurs in Al+SnCl4 ? and what is the balanced equation
Monday, February 29, 2016 by Camila

Chemistry
What is delta h for reaction between h2o2 and ethene to give ethylene glycol if HO-OH is 49 kcal/mol and C=C 65 kcal/mol Please show ur work
Monday, February 29, 2016 by Brahamanand

Chemistry
I need major help with balancing redox reactions. I can't seem to get this one: (in basic conditions) NBr_3(aq)=> N_2(g) + Br^-(aq) + HOBr(aq) I don't know how to split this up properly, and when I do it is like impossible to balance it. Thanks!
Monday, February 29, 2016 by Betty

Chemistry
What is the final temperature and physical state of water when 250 grams of water at 85 degrees C is added to 80.0 grams of ice at -15 degree C? Is the physical state of water liquid? I don't understand the set up. The setup is like this (answered by bobpursly): The sum of...
Monday, February 29, 2016 by Student

Chemistry
CH4 (g)+ H2O (g) --->/<---- 3H2 + CO Use Le Chateliers Principle to explain what will happen to the number of moles of hydrogen at equilibrium when a) CO is removed b) Water Vapor is removed c) Methane is added d) CO is added e) Pressure is increased by adding argon gas...
Monday, February 29, 2016 by Student

Chemistry... again
How does a polar bond differ from a nonpolar bond? Explain your answer. All I need are ideas, not the word-for-word answer.
Monday, February 29, 2016 by Leet Speaker

Chemistry
Highest ionization energy to lowest I be ci f
Monday, February 29, 2016 by Anonymous

Chemistry
If you make a solution in the laboratory that contains 0.1 M acetic acid (CH3COOH), what concentration of hydronium will you have once the solution equilibrates?
Monday, February 29, 2016 by Rose

Chemistry
If you make a solution in the laboratory that contains 0.1 M hydrochloric acid, what concentration of hydronium will you have?
Monday, February 29, 2016 by Rose

chemistry
1. what mass of sodium hydroxide is required to make up 100 mL of 0.5000M solution 2.What volume of this solution must be diluted down to 100 mL if 0.100M solution of NaOH is required?
Monday, February 29, 2016 by Anonymous

Some Chemistry Questions
I got three questions. If you were making a tool used to handle live electrical wires, which class of materials would you most likely use? ***Semimetals Metalloids Nonmetals Metals Which of the following changes gives no evidence that a chemical reaction has taken place? A ...
Monday, February 29, 2016 by Leet Speaker

Chemistry
what is the concentration of each substance if a solution is prepared by mixing 5.00g of NaC2H3O2 with 15.0 ml of 1.45M acetic acid and then bringing the total volume to 250.0 ml?
Monday, February 29, 2016 by Ali

Chemistry
CH4 (g)+ H2O (g) --->/<---- 3H2 + CO Use Le Chateliers Principle to explain what will happen to the number of moles of hydrogen at equilibrium when a) CO is removed b) Water Vapor is removed c) Methane is added d) CO is added e) Pressure is increased by adding argon gas...
Monday, February 29, 2016 by Student

Chemistry
What is the final temperature and physical state of water when 250 grams of water at 85 degrees C is added to 80.0 grams of ice at -15 degree C? Is the physical state of water liquid? I don't understand the set up that I have to set the equation equal to 0 ...
Monday, February 29, 2016 by Student

Chemistry
The pH of a 0.095 M solution of an unknown monoprotic acid is 5.42. Calculate the Ka of the acid. A) 3.8 x 10-6 B) 3.6 x 10-7 C) 1.5 x 10-10 D) 2.6 x 10-9 E) 2.8 x 10-8 ​
Monday, February 29, 2016 by Bronwyn

Chemistry
I got 1.11 x 10^-6 for K. Here is my work: x= 0.004 -2x= -0.008 (change for CH4) Equilibrium for CH4 is 0.087 - 0.008= 0.079 Change in eq for C2H2 is 0.004 and eq is 0.004 (=x) Change in eq for H2 is 0.012 Eq for H2 is 0.012 K= [C2H2][H2]^3/[CH4]^2 K= (0.004)(0.012)^3/(0.079)^...
Monday, February 29, 2016 by Student

Chemistry
What is the value of the equilibrium constant for the overall reaction? ​​ AgCl (s) + 2NH3 (aq) Ag(NH3)2+ (aq) + Cl- (aq) Knet = ?
Monday, February 29, 2016 by Bronwyn

Chemistry
How many milliliters of 2.00 M NaHO solution are needed to neutralize a 8.00 mL of 3.50 M H2SO4 solution?
Monday, February 29, 2016 by Hailey

Chemistry
I need to write a hypothesis on limiting reactants.
Monday, February 29, 2016 by Keron

cHEMISTRY
What mass of AgCl(143.32g/mol) is formed from the reaction of a 0.109 M MgCl2 solution with excess AgC2H3O2?
Monday, February 29, 2016 by lIZ

Organic Chemistry
Hello, I have done an experiment in Organic Chemistry called :SN1 Reaction: Synthesis of t-amyl chloride from t-amyl alcohol, there are some questions that I am unsure about, 1) What are the 2 rules of HCl in this reaction? Can you use NaCl instead of HCl to synthesize t-amyl ...
Monday, February 29, 2016 by Mohammed

Chemistry
calculate the bond energy for diatomic oxygen O2 given that standard enthalpy of atomization of oxygen (ΔH) = 249.17KJ
Monday, February 29, 2016 by Solomon

Chemistry
The reaction of CH4 in 2CH4(g) ---->/<---- C2H2(g) + 3 H2 (g) is carried out at a different temperature with an initial concentration of [CH4]=0.087M. At equilibrium, the concentration of H2 is 0.012 M. Find the equilibrium constant at this temperature.
Sunday, February 28, 2016 by Student

chemistry
A solution containing 29.00 mg of an unknown protein per 22.0 mL solution was found to have an osmotic pressure of 3.10 torr at 18 ∘C. What is the molar mass of the protein? (3.10 torr* 22mL)=.682 I do not know what to do next
Sunday, February 28, 2016 by mmp

Chemistry
What volume (in milliliters) of 0.170 M NaOH should be added to a 0.140 L solution of 0.021 M glycine hydrochloride (pKa1 = 2.350, pKa2 = 9.778) to adjust the pH to 2.84? I tried using the Henderson- Hasselbalch equation but I am confused about what to do with the answer to ...
Sunday, February 28, 2016 by L

Chemistry
I did a lab, an kinetics lab (iodide clock) and in my lab report I have to calculate the initial rate in mol L-1 s-1 and I'm not sure how to do that. I have the [I-] and [S2O82-] in mol L-1 already. The reagents are [KI] [NaCl] [Na2S2O3] [Na2SO4] [K2S2O8].
Sunday, February 28, 2016 by Dan

Chemistry
Help! I have to get this done tonight and I cannot get this answer right. A solution of water (Kf=1.86 ∘C/m) and glucose freezes at − 3.55 ∘C. What is the molal concentration of glucose in this solution? Assume that the freezing point of pure water is 0.00 &#...
Sunday, February 28, 2016 by Emmalee

Chemistry
A 70.0 mL solution of 0.171 M potassium alaninate (H2NC2H5CO2K) is titrated with 0.171 M HCl. The pKa values for the amino acid alanine are 2.344 (pKa1) and 9.868 (pKa2), which correspond to the carboxylic acid and amino groups, respectively. a) Calculate the pH at the first ...
Sunday, February 28, 2016 by Bobby

Chemistry
What volume (in milliliters) of 0.100 M NaOH should be added to a 0.120 L solution of 0.024 M glycine hydrochloride (pKa1 = 2.350, pKa2 = 9.778) to adjust the pH to 2.95? I dont know how to do this problem! Steps with answers please!! HELP!!
Sunday, February 28, 2016 by Bobby

SCIENCE
jamal's neighbor tells him that there are more bacterial cells than human cells in his body. which of these is the best reason that jamal should question his neighbors statement? a. jamal is older than his neighbor b. jamal does not like his neighbor very much. c. his ...
Sunday, February 28, 2016 by John Doswell

Chemistry
When 50 grams of hydrocarbon X are burned with oxygen the products are carbon dioxide and water. If 65 grams of water and 100 grams of carbon dioxide are produced, how many grams of oxygen were needed for the reaction? This was a question on my chemistry homework but I'm ...
Sunday, February 28, 2016 by Ryan

Science Help
jamal's neighbor tells him that there are more bacterial cells than human cells in his body. which of these is the best reason that jamal should question his neighbors statement? a. jamal is older than his neighbor b. jamal does not like his neighbor very much. c. his ...
Sunday, February 28, 2016 by John Doswell

Chemistry
In a volumetric analysis experiment, a solution of sodium oxalate in acidic soltuion is titrated with a solution of potassium permanganate according to the following balanced chemical equation: 2KMnO4+8H2SO4+5Na2C2O4 -> 2MnSO4+8H2O+10CO2+5Na2SO4+K2SO4 What volume of .0239 M...
Sunday, February 28, 2016 by Kaley

Chemistry
What is the strongest intermolecular force present in each molecule: H2S CF4 NH3 CS2 PCL3 N CH2O C2H6 CH3OH BH3 My work: Hydrogen bonding London dispersion Dipole dipole London dispersion Dipole dipole London dispersion Hydrogen bonding Hydrogen bonding Hydrogen bonding Am I ...
Sunday, February 28, 2016 by Rose

chemistry
what would be observed when combining an aqueous mixture of: potassium carbonate and hydrochloric acid, zinc chloride and silver nitrate, magnesium chloride and sodium hydroxide, ammonium nitrate and sodium hydroxide?
Sunday, February 28, 2016 by sarah

chemistry
The standard internal energy change for a reaction can be symbolized as ΔU°rxn or ΔE°rxn. For the following reaction equations, calculate the energy change of the reaction at 25 °C and 1.00 bar. Sn(s) + 2Cl2(g) --> SnCl4(l) ΔH°rxn = -511.3 kJ/...
Sunday, February 28, 2016 by jake

chemistry
1.what are the functions of pH?
Sunday, February 28, 2016 by sarah

Chemistry
Why a benzene ring sometimes gives -I effect? Why is No2 is more electron withdrawing then CN?
Sunday, February 28, 2016 by Anand rajput

Chemistry
If milk is refrigerated in containers of glass, plastic and cardboard, in which container to you believe the milk will have the most increase in lactic acid?
Sunday, February 28, 2016 by Jennifer

chemistry
calculate joules release when 175g of steam condenses at 100c and cool the liquid to 35.00c
Saturday, February 27, 2016 by linda

Food Chemistry
A heat exchanger is used to warm apple cider using steam as the heat source. The cider is heated from an initial temperature of 4°C to a final temperature of 65°C. The steam enters the heat exchanger as 50% quality steam and exits as water condensate at 85°C. ...
Saturday, February 27, 2016 by Ashwaa

Chemistry
Write the balanced equation for the neutralization reaction between H3PO4 and NaOH in aqueous solution. Phases are optional.
Saturday, February 27, 2016 by Dane

Chemistry
What is the molarity of a solution that results when 3.64 g KCl is dissolved in water and diluted to exactly 200.0 mL?
Saturday, February 27, 2016 by Van

Chemistry
I have to summarize 10 articles relating to the topics we had covered in class. However, there are 3 sources out of the 10 that I don't understand. Could someone possibly go through the sources and summarize them. 1.) This article covers Nuclear Chemistry (Nuclear Reactors...
Saturday, February 27, 2016 by Jess

analytical chemistry
what is the volume that must be added to dillute 20.0 ml of 0.1M Hcl to 0.02M Hcl
Saturday, February 27, 2016 by francime

Chemistry
An interference filter is to be constructed for isolation of the nitrobenzene absorption band at 1537 cm-1. (a) If it is to be based on first-order interference, what should be the thickness of the dielectric layer (refractive index of 1.34)? (b) What other wavelengths would ...
Saturday, February 27, 2016 by Aaron

Chemistry
Calculate the volume of hydrogen produced at s.t.p when 25g of zinc are added to excess dilute hydrochloric at 3degree and 778mmhg pressure
Saturday, February 27, 2016 by Jubilee

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Homework Help: Science