Saturday
August 29, 2015

Homework Help: Science: Chemistry

Recent Homework Questions About Chemistry

Chemistry
A half-cell that consists of a copper wire in 1.00 M CuNO3 solution is connected by a salt bridge to a half cell containing a 1.00 M X(II) acetate solution and an electrode of metal X. The voltage of the cell is 2.00 V, with metal X as the positive electrode. Calculate the ...
Sunday, April 12, 2015 by JUNDY

Chemistry
What is the oxidation state assigned to Cr in zinc dichromate, ZnCr2O7?
Sunday, April 12, 2015 by JUNDY

Chemistry
Identify the correct statement for the following reaction: Br2 (l) → Br2 (g) ΔH° = 30.9 kJ ΔS° = 93.2 J/K A) The reaction is always spontaneous. B) The reaction is never spontaneous. C) The reaction is at equilibrium; therefore, ΔG° = 0. D) The...
Sunday, April 12, 2015 by Chase

Chemistry
Which of these substances has the highest molar entropy? A) C2H4 (g) B) CH3CH2OH (l) C) SO3 (g) D) CH3CH3 (g) E) C6H12O6 (g)
Sunday, April 12, 2015 by Kate

chemistry
hi, need help.. use the atomic weight of carbon and chlorine to determine the theoretical value of the molecular weight of CH3OH(I've calculate the average mr of CH3OH -->0.39g/mol).(atomic weight: c= 12.0, cl= 35.5)
Sunday, April 12, 2015 by joy

chemistry higher
calculate the volume of hydrogen produced when 6g of magnesium is reacted with 100cm of 1 mol l-1 hydrochloric acid no of moles of Mg= mass/gfm = 6/24.3 = 0.247 moles 1/2 mole of Mg= 1/2 mole of H2 = 0.247 moles x 100 = 24.7cm3 ???
Sunday, April 12, 2015 by iain

Chemistry - Help
Please help..Write the equation for the equilibrium constant (K) of the reaction. 2K2CrO4 + 2HCl --><-- Cr2O7 + H2O + 2KCl (K2CrO4 is chromate) and (Cr2O7 is dichromate)
Sunday, April 12, 2015 by Angie

Chemistry
Put 10 mL of silver sulfate (Ag2SO4) in 1 gram zinc. What is the net equation?
Sunday, April 12, 2015 by Chase

chemistry
what is ion pair formation in regards to extractions
Sunday, April 12, 2015 by extractions

Chemistry
a 5.00 gram sample of a metal is heated to 80 degrees Celsius and is placed in a 100 gram sample of water. the temperature of the water rises from 20 Celsius to 20.3 Celsius which of these is most likely to be the metal
Sunday, April 12, 2015 by Hazard

chemistry
a solution of kcl contains 10. grams of kcl in 100. ml of water at 30c. how many additional grams of kcl are needed to saturate the solution?
Saturday, April 11, 2015 by :))

Chemistry
What is the change in entropy when 9.30 mL of liquid benzene (C6H6, d = 0.879 g/mL) is burned in the presence of 37.2 L of oxygen gas, measured at 298 K and 1 atm pressure? 2C6H6(l) + 15O2(g) → 12CO2(g) + 6H2O(l); ∆S° = –437.7 J/K at 298 K
Saturday, April 11, 2015 by Jonathan

chemistry
Suppose 50mL of 8.4 x 10^-7 M Pb(NO3)2 (aq) is mixed with 200 mL of 9.7 x 10 ^-4 M Na2CO3 (aq). Calculate Q and determine whether a ppt of PbCO3(s) will form.
Saturday, April 11, 2015 by Donna

chemistry
A buffer with a pH of 4.30 contains 0.25 M of sodium benzoate and 0.20 M of benzoic acid. What is the concentration of [H ] in the solution after the addition of 0.052 mol of HCl to a final volume of 1.5 L? I know that Ka = 6.3x10-5 do I need to use an ice table or is the pH=...
Saturday, April 11, 2015 by noel

Chemistry
Consider this reaction: 3 K2CO3 (aq) + 2 CrCl3 (aq) -> Cr2(CO3)3 (s) + 6 KCl (aq) If 1.2 moles of CrCl3 react, how many moles of K2CO3 will react with it? A. 0.80 mol K2CO3 B. 1.2 mol K2CO3 C. 1.8 mol K2CO3 D. 2.4 mol K2CO3 I'm not sure where to even begin, I know how ...
Saturday, April 11, 2015 by Mischa

Chemistry: Acids/Bases
When a 100 mM aq solution of sodium acetate was prepared in the lab it had a pH of 8.9. Calculate the amount of acetic acid (in g) to be added to 0.5 L of this sodium acetate solution in order to bring its pH to the target value of 5.00.
Saturday, April 11, 2015 by Tim

Chemistry (solubility product question)
"When 3.00 ml of a 0.00600 M K2CrO4 solution and 3.000 ml of a 0.0100 M Cu(NO3)2 solution are mixed, some solid forms. The mixture is centrifuged and the supernatant is removed. The absorbance of the supernatant, measured at 400 nm in a 1.00 cm cuvette, is 0.286. The ...
Friday, April 10, 2015 by Nikki

chemistry
I understand part (I) but We have only briefly gone over the HH equation in class and I understand how to use it to get the pH but I really don't understand how to use it in part (II), assuming I should be using it in this question? (I)Calculate the pH of an acetate buffer...
Friday, April 10, 2015 by Tim

Chemistry
Gaseous ethane will react with gaseous oxygen to produce gaseous carbon dioxide and gaseous water . Suppose 16.2 g of ethane is mixed with 19. g of oxygen. Calculate the maximum mass of carbon dioxide that could be produced by the chemical reaction. Round your answer to ...
Friday, April 10, 2015 by Katie

chemistry
An optically active compound A, C6H10O2, when dissolved in NaOH solution, consumed one equivalent of base. On acidification, compound A was slowly regenerated. Treatment of A with LiAlH4 in ether followed by protonolysis gave an optically inactive compound B that reacted with ...
Friday, April 10, 2015 by Joseph

chemistry
determine the pressure in a 0.34 liter balloon if the temperature is 35 celsius and the balloon contains 0.0233 mol of an ideal gas.
Friday, April 10, 2015 by Anonymous

chemistry
How much volume of a 1.5 M KOH is needed to extract a carboxylic acid from a mixture of 2.450 gram of benzoic acid and a 2.080 g of acetanilide? This is a liquid liquid extraction.
Friday, April 10, 2015 by siarrh

Chemistry
How much volume of a 1.5 M KOH is needed to extract a carboxylic acid from a mixture of 2.450 gram of benzoic acid and a 2.080 g of acetanilide?
Friday, April 10, 2015 by Siarrh

chemistry
For the weak hypochlorous acid (HClO), which statement is true at the point halfway to the equivalence point? A. The total amount of HClO is equal to the pKa. B. The total amount of HClO is equal to ClO-. C. The total amount of H3O+ is equal to the amount of OH- . D. The total...
Thursday, April 9, 2015 by Cortney

Chemistry
A 54.7-g sample of aluminum at 95.0°C is dropped into 35.0 g of water at 40.0°C. What is the final temperature of the mixture? (specific heat capacity of aluminum = 0.89 J/g°C; specific heat capacity of water = 4.184 J/g°C)
Thursday, April 9, 2015 by Deanne

Chemistry
If 30 ml of 02 M HCL with 45 ml what is the molarity of NaOH
Thursday, April 9, 2015 by Melissa

Chemistry
Can you help me calculate the maximum weight-percent of H present in liquid iron containing 0.16 wt% Oxygen and equilibrated with H2O(g) at a pressure of 0.164 atm at 1600°C. Given ÄG° = -207653 + 0.292T J and assume that O and H both obey Henry’s law.
Thursday, April 9, 2015 by Brian James

chemistry
a 100 gram sample of a metal undergoes a temperature change from 20 C to 50 C Absorbing 1500J of heat
Thursday, April 9, 2015 by Jayden

chemistry
What volume of a 0.553 M calcium hydroxide solution is needed to exactly neutralize 7.34 grams of KHP
Thursday, April 9, 2015 by Pam

chemistry
how many grams of CaCI would be required to produce a 8.5M (molar) solution with a volume of 2.0L
Thursday, April 9, 2015 by Anonymous

chemistry
how many grams of CaCI would be required to produce a 85M (molar) solution with a volume of 2.0L
Thursday, April 9, 2015 by Anonymous

Chemistry
calculate oh- and ph in a solution in which dihydrogen phosphate ion is 0.335 M and hydrogen phosphate is 0.335 M. This is a homework question, where I have the solution, which is 0.335/0.335, which I get, but then I am supposed to multiply this (1)by a number 6.2x10-8? I have...
Thursday, April 9, 2015 by Jessica

Chemistry
H2 +Br2 =2HBr so suggest twoo reasons why all the collisions between hydrogen and bromine gas molecules do bot result in reaction?
Thursday, April 9, 2015 by Thamathama

chemistry
500 mL Of hydrogen at 27 degrees celcius and 3 atms pressure is compressed to 100 mL at 100 degrees celsius. What is the new pressure in atms?
Thursday, April 9, 2015 by Ana

Chemistry
In the reaction Ca(OH)2 + 2HCL -> CaCl2 + 2H2O: How many kilograms of H2O will be produced when 0.0948 Kg of Ca(OH)2 react with excess hydrochloric acid?
Thursday, April 9, 2015 by Ana

Chemistry
The volume of the nitrogen gas is 125ml atmospheric pressure is 763mm Hg Water temperature is 24 degrees Celcius. The water level inside the eudiometer is the same as the level of water in the beaker. Calculate the pressure of the dry nitrogen gas. PH2=Ptotal-PH2O PH2=763 mm ...
Thursday, April 9, 2015 by Maddy

Chemistry
Laughing gas (nitrous oxide, N2O) is sometimes used as an anesthetic in dentistry. It is produced when ammonium nitrate is decomposed according to the reaction NH4NO3(s) −! N2O(g) + 2H2O(§¤) . How much NH4NO3 is required to produce 54.5 g of N2O? Answer in ...
Thursday, April 9, 2015 by danny

chemistry
Phosphorus reacts with water to form hydrochloric acid and phosphoric acid. how many moles of acid are formed when starting with 4.5 g of PCl5 and excess H2o?
Thursday, April 9, 2015 by Michael

Chemistry (Acid/Base)
Consider a solution made by mixing 100 mL of 2.0 M acetic acid (Ka= 1.8e-5) with 100 mL of 0.00020 M benzoic acid (Ka= 6.4e-5). How many moles of solid NaOH must be added to the solution so that half of the benzoic acid is protonated (i.e. such that [HA] = [A-] for benzoic acid)?
Thursday, April 9, 2015 by Emily

Chemistry
027 (part 1 of 3) 10.0 points Copper reacts with silver nitrate through single replacement. If 3.03 g of silver are produced from the reaction, how much copper(II) nitrate is also produced? Answer in units of mol. 028 (part 2 of 3) 10.0 points How much Cu is required in this ...
Thursday, April 9, 2015 by danny

chemistry
28g of N2 and 6g of H2 were kept at 400 degree centigrade,the equilibrium mixture contained 27.54g of NH3. Find the value of Kc in mole^-2L^2 .
Thursday, April 9, 2015 by abhishek

Chemistry
Calculate the mass of water formed by the complete reaction of 572 g of propane (C3H8) with excess oxygen. (Write a balanced equation.) Answer in units of g.
Thursday, April 9, 2015 by danny

Chemistry
Write a balanced equation for the combustion of gaseous propane (C3H8), a minority component of natural gas, in which it combines with gaseous oxygen to form gaseous carbon dioxide and gaseous water. I answered C3H8 + 5O2 = 3CO2 + 4H2O but it was wrong, any idea why?
Thursday, April 9, 2015 by Basel

chemistry
When an ion-selective electrode for X was immersed in 0.0210 M XCl, the measured potential was 0.0480 V. What is the concentration of X when the potential is 0.0630 V? Assume that the electrode follows the Nernst equation, the temperature is at 25°C, and that the activity ...
Wednesday, April 8, 2015 by tevon

chemistry
What types of intermolecular forces allow CO2 to dissolve in water? Do CO2 and H20 have a relatively strong or weak attraction?
Wednesday, April 8, 2015 by emily

Chemistry
Calculate the molar solubility of Mg(OH)2 in the following solvents: (i) 8.60×10−2M MgCl2 (ii) 3.70×10−2M KOH(aq) Please help!!!
Wednesday, April 8, 2015 by Anonymous

Chemistry
A professor wanted to set up a similar experiment as the one you performed in lab. The professor wanted to use Al(OH)3 in place of Ca(OH)2. Calculate how many mL of saturated Al(OH)3 solution it would take to titrate against 12.00mL of 0.0542M HCl solution? The Ksp of Al(OH)3 ...
Wednesday, April 8, 2015 by Caroline

Chemistry
Calculate the molar solubility of Mg(OH)2 in the following solvents: (i) Pure Water (ii) 8.60×10−2M MgCl2 (iii) 3.70×10−2M KOH(aq) How should i solve this problem?
Wednesday, April 8, 2015 by Anonymous

Chemistry
For a solution that is 0.168M NH3 and 0.106M NH4Cl calculate the following. [OH-] [NH4+] [Cl-] [H30+]
Wednesday, April 8, 2015 by Anonymous

Chemistry
For the equation: MnO2 (s) + 2 CO (g) → Mn (s) + 2 CO2 (g) Calculate ΔG at 298K if MnO2 = 0.150 mol, Mn = 0.850 mol, CO = 0.250 M and CO2 = 0.500 M in a 1.25 L flask.
Wednesday, April 8, 2015 by Chase

chemistry
The partial pressure of fluorine gas (F2) in a mixture of gases where the total pressure is 1.00 atm is 300. torr. What percent of the mixture is made of fluorine gas
Wednesday, April 8, 2015 by cheater

chemistry
How much mL of 0.5m HCL would it take to compeletly react with 3.00g CaCO3?
Wednesday, April 8, 2015 by paty

chemistry
The partial pressure of fluorine gas (F2) in a mixture of gases where the total pressure is 1.00 atm is 300. torr. What percent of the mixture is made of fluorine gas
Wednesday, April 8, 2015 by cheater

Chemistry
Calculate ΔG at 298K if MnO2 = 0.150 mol, Mn = 0.850 mol, CO = 0.250 M and CO2 = 0.500 M in a 1.25 L flask.
Wednesday, April 8, 2015 by Kate

science (chemistry)
why does the pH of the acid solution initially increase very slowly when metal is first added to the acid solution, but gradually increase at a faster rate as the reaction proceeds to completion? I thought it may be because the metal is just then being completely dissolved but...
Wednesday, April 8, 2015 by brittany

chemistry
if 0.600 moles of copper(II) sulfide is treated with 1.40 moles of nitric acid, how many moles of copper(II) nitrate could be produced?
Wednesday, April 8, 2015 by Carmen

chemistry
Suppose that 2.00mL of 0.02 mol/L aqueous sodium sulphide, Na2S is used to test a 60.0mL sample of water containing 0.0004 mol/L mecury (II) nitrate Hg(NO3)2, ions. a. Write the balanced equation Hg(NO3)2 + Na2S = HgS + 2NaNO3 b. Determine the limiting reactant Na2S = 2.00mL/...
Wednesday, April 8, 2015 by sharon

Chemistry
A chemical reaction yields 3 moles of lithium hydroxide (LiOH). How many grams of lithium hydroxide are present? 24 g 48 g 72 g When ethane (C2H6) burns, it produces carbon dioxide and water: 2C2H6 (g) + 7O2 (g) 4CO2 (g) + 6H2O (l) How many moles of water will be produced when...
Wednesday, April 8, 2015 by jimm

chemistry
Convert 75.0 psi to atm My work: 75.0psi x 1 psi/14.7 atm =5.10 atm Not sure if this is set up right we are using dimensional analysis
Wednesday, April 8, 2015 by sarah

chemistry
how many electrons can n=4 l=1 have?
Wednesday, April 8, 2015 by Alex

chemistry
A piece of metal of mass 18 g at 104 ◦C is placed in a calorimeter containing 47.4 g of water at 22◦C. The final temperature of the mixture is 40.8 ◦C. What is the specific heat capacity of the metal? Assume that there is no energy lost to the surroundings.
Tuesday, April 7, 2015 by kika

Chemistry
In a chain mechanism, a reaction in which two free radicals combine to form a stable molecule would be called the A) initiation step B) termination step C) propagation step D) inhibition step E) branching step
Tuesday, April 7, 2015 by Haley

Chemistry
If the reaction 2NO + 2H2 --> N2 + 2H2O occurred in just a single step, the overall order of the reaction would be A) 1 B) 2 C) 3 D) 4 E) 5
Tuesday, April 7, 2015 by Haley

Chemistry
Explain why the solubility of KHTar in 0.100 M NaCl solution differs from that in pure water? Explain why the solubility of KHTar in the mixed KCL - NaCl solution differs from that in the 0.100 M NaCl.
Tuesday, April 7, 2015 by Haley

Chemistry
A coffee cup calorimeter contains 100.0 g of water at 10.0 ◦C. A 72.4 g sample of iron is heated to 100 ◦C and dropped into the calorimeter. Assuming there is no heat lost to the coffee cup, calculate the final temperature of the system. The specific heats of iron ...
Tuesday, April 7, 2015 by kika

Chemistry
At 20 degrees celcius the vapor pressure of toluene is 22 mmhg and that of benzene is 75 mmhg. Assume an ideal solution, equimolar in benzene and toluene. At 20 degrees celcius what is the mole fraction of benzene in the vapor in equilibrium with this solution? If you use pv=...
Tuesday, April 7, 2015 by Marissa

chemistry
If you start with 146 g of water at 47◦C, how much heat must you add to convert all the liquid into vapor at 100◦C? Assume no heat is lost to the surroundings. Answer in units of kJ.
Tuesday, April 7, 2015 by kika

Applied Chemistry - HELP!
Make a poster of types of product warning labels. I'm having a hard time looking up types of product warning labels. Please help and please do not just give me Google link to product label for me to look up by myself which I did but I .... having a hard time.
Tuesday, April 7, 2015 by Sam

Chemistry
I don't understand this one at all. Please help! For the equation: MnO2 (s) + 2 CO (g) → Mn (s) + 2 CO2 (g) 1. Calculate ΔG° at 25°C 2. Calculate ΔG° at 125°C
Tuesday, April 7, 2015 by Kate

Chemistry
24.0 mL of a 2.4 M silver nitrate is mixed with 32.0 mL of 2.0 M sodium. Calculate the mass of precipitae formed. Calculate the concentration of all ions remaining in solution after the precipitate forms. I don't know how to start this or where to go with it...
Tuesday, April 7, 2015 by Marissa

chemistry
16.5 mL of 2.5 M sodium sulfate is mixed with 35.5 mL of 4.5 M sodium nitrate. What is the concentration of all ions in the new solution?
Tuesday, April 7, 2015 by Marissa

Analytical Chemistry
Serum taken from a patient being treated with lithium for manic-depressive illness was analyzed for lithium concentration. A reading of 3.00xE2 units was obtained for the intensity of the 671 nM red emission line. Then 1.00 mL of a 11.8 mM Lithium standard was added to 9.00 mL...
Tuesday, April 7, 2015 by teresmajor16

Chemistry
Calculate the vapor pressure of Hg at 14 oC (in atm). Hg(l) ↔ Hg(g) . . . ΔHo = 61.32 kJ and ΔSo = 98.83 J/K
Tuesday, April 7, 2015 by JUNDY

Chemistry
Calculate the average C—C bond strength in cyclopropane (in kJ/mol). Its combustion and the experimental enthalpy of reaction are: C3H6(g) + 4.5O2(g) → 3CO2(g) + 3H2O(g) ΔHºrxn = -1,957.7 kJ/mol Since all reactants and products are in the gaseous state, ...
Tuesday, April 7, 2015 by JUNDY

chemistry
Find (triangle)H for N2H4 + CH4O > C2HO + N2 + 3H2 2NH3 > N2H4 + H2 22.5 kJ 2NH3 > N2 + 3H2 57.5 kJ CH20 + H2 > CH4O 81.2 kJ
Tuesday, April 7, 2015 by Anonymous

Chemistry
What is the molarity of a solution containing 10.g of NaOH in 700.mL of NaOH solution? Express your answer to two significant figures and include the appropriate units.
Tuesday, April 7, 2015 by Chan

Chemistry
Determine the volume, in milliliters, required to prepare each of the following diluted solutions. 40.0mL of a 2.75M KNO3 solution using a 1.00M KNO3 solution 45.0mL of a 2.90M H2SO4 solution using a 6.00M H2SO4 solution 0.700L of a 2.10M NH4Cl solution using a 5.00M NH4Cl ...
Tuesday, April 7, 2015 by Chan

Chemistry
Calculate the molarity (M) of the following solutions: 4.00moles of glucose in 3.00L of glucose solution 5.50g of KOH in 4.00L of KOH solution 5.85g of NaCl in 400.mL of NaCl solution
Tuesday, April 7, 2015 by Chan

Chemistry
Calculate ΔG (in kJ) at 298 K for some solid ZnF2, 0.055 M Zn2+ and 0.063 M F-(aq). I found Q to be 2.18e-4, then i implemented it into the equation deltaG=RT(lnQ). I got -20.89, but the answer is -12.2.
Tuesday, April 7, 2015 by JUNDY

chemistry
What must be true for a substance to dissolve in water? A. The entropy term must be positive. B. The enthalpy and entropy terms must combine for a favored reaction. C. The free energy change of dissolving must be positive. D. The energy required to break bonds apart must be ...
Tuesday, April 7, 2015 by Cortney

Chemistry
An aqueous solution of 0.25 M silver nitrate, AgNO3, and 0.25 M iron(II) nitrate, Fe(NO3)2, are allowed to come to equilibrium in the following chemical reaction:
Ag+(aq) + Fe2+(aq) Fe3 + (aq) + Ag(s)
If the equilibrium constant, Kc, for the reaction is 3.0 ×...
Tuesday, April 7, 2015 by Cortney

Chemistry
If you have 225 grams of Ca3(PO4)2, and 185g H3PO4; calculate which is the limiting reagent, which the XS reagent, and how much product you will produce from the limiting reagent (in grams) Ca(PO4)2 + 4H3PO4 = 3Ca(H2PO4)2
Tuesday, April 7, 2015 by Emily

Chemistry
If you need to produce 355 grams of oxygen gas (O2) in the electrolysis reaction of water by an electric current. If the reaction is run at 125 degrees Celsius in a reactor volume 22500ml. What is the pressure of the produced oxygen in mm Hg?
Tuesday, April 7, 2015 by Emily

Chemistry
If you have a 1255ml of a 10.55 M solution of HCl and you need to dilute the solution to 1.555 M solution; How much solvent must you add?
Tuesday, April 7, 2015 by Emily

Chemistry
In a 25.8 liter vessel of nitrogen gas that is heated from 10 degrees Celsius to 110 degrees Celsius to reach a final pressure of 17450 mm Hg; how many grams of N2 do you have in the vessel?
Tuesday, April 7, 2015 by Emily

Chemistry
What are the correct and accurate products for the following ion combination reaction? Then write the ionic form of the reaction and the net ionic form of the reaction. K2CO3 + CaCl2 ->
Tuesday, April 7, 2015 by Emily

Chemistry
What are the correct and accurate products of the following neutralization reaction. Then write the ionic form of the equation and the net ionic form. KOH + H2SO4 ->
Tuesday, April 7, 2015 by Emily

chemistry cp
The term formula mass is a general term that can be applied to both ionic compounds and molecular compounds because (a) ionic compounds exist as individual molecules (b) molecular formulas are always empirical formulas (c) not all formulas represent individual molecules (d) ...
Tuesday, April 7, 2015 by sally

Chemistry
1. If two moles of ZnCl2 separate into Zn+ and Cl- ions, how many moles of Zn+ ions are present? 2. How many moles of NO3- are present in one mole of Mg(N03)2? The answers to both of these are 1 mole, right?
Tuesday, April 7, 2015 by G

Chemistry
What is the mass in grams of 6.5 moles of water? could you show me how you get the answer to
Tuesday, April 7, 2015 by jimm

Chemistry
C18H32O2 + 2H2 - C18H3602; oxidized or reduced?
Tuesday, April 7, 2015 by Maria

chemistry
Describe the following types of corrosion and give a practical example of each 1.pure chemical corrosion 2.pure electrochemical corrosion
Tuesday, April 7, 2015 by aneleeeee

Chemistry
What is the volume, in milliliters, required to prepare a. 20.0 mL of a 0.250 M KNO3 solution using a 6.00 M KNO3 solution b. 25.0 mL of a 2.50 M H2SO4 solution using a 12.0 M H2SO4 solution c. 0.500 L of a 1.50 M NH4Cl solution using a 10.00 M NH4Cl solution
Monday, April 6, 2015 by Anonymous

Chemistry
Sodium vapor lamps are often used in residential street lighting. Sodium gives off two yellow lines of light having frequencies of 5.09 × 1014 Hz and 5.08 × 1014 Hz. What is this wavelengths of light in nm? would I start by using the following formula ƛ=c/v &#...
Monday, April 6, 2015 by Stacie

Chemistry
The Ka for the reaction of acetic acid and water is 1.8 x 10-5. Which of the following statements is true at pH 7? A.) there is much more acetic acid than acetate ion B.) there is more acetate ion than acetic acid C.) the concentration of acetate ion is equal to that of acetic...
Monday, April 6, 2015 by Kristin

Chemistry
The ethylammonium ion, CH3CH2NH3+, has a pKa of 10.81. It reacts with water to form ethylamine, CH3CH2NH2 and H3O+. Which of the following statements is true at pH 7? A.) ethylamine predominates B.) ethylammonium ion predominates C.) the pH is higher than pKa of the ...
Monday, April 6, 2015 by Kristin

Chemistry
If you have 324 grams KBr and want to produce a 1.48 M solution in water how many grams of water are needed?
Monday, April 6, 2015 by Angela

Chemistry
Can anyone help me identify the solute and solvent in each solution with the steps if possible? Thanks! a. 10mL of acetic acid and 200mL of water b. 100.0g of water and 5.0g of sugar c. 1.0mL of Br2 and 50.0mL of methylene chloride
Monday, April 6, 2015 by Anonymous

Chemistry (isotonicity)
How many milligrams of NaCl should be used to make the following prescription isotonic? Dextrose anhydrous 2.5% Sodium chloride q.s. Sterile water for injection Ad 1L There is only dextrose anhydrous 5% available
Monday, April 6, 2015 by herry

chemistry
a container with an initial volume of 6 liters at a temperature of 30 degrees celsius with a pressure of 2atm is changed so the temperature is now 90 degrees celsius and the volume is 8 liters. calculate the new pressure
Monday, April 6, 2015 by Anonymous

  1. Pages:
  2. <<Prev
  3. 5
  4. 6
  5. 7
  6. 8
  7. 9
  8. 10
  9. 11
  10. 12
  11. 13
  12. 14
  13. 15
  14. 16
  15. 17
  16. 18
  17. 19
  18. Next>>

Homework Help: Science

Members