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Homework Help: Science: Chemistry

Recent Homework Questions About Chemistry

chemistry
Why can't you form an acid salt from a monoprotic acid?

chemistry
How much heat in kJ is required to increase the temperature of an 87.0 g sample of water from 67oC to 136.6oC?

chemistry (I have a test tomorrow)
4 Ag + 2 H2S + O2 = 2 Ag2S + 2 H2O a) What mass if silver sulfide is formed from the reaction of 0.120g of silver? b) What mass of hydrogen sulfide is needed in the same process? So I understand a, and I found the answer to be 0.138g. For b the text book says the answer is 0....

chemistry
In the predicted electron configuration of Molybdenum (Mo), how many electrons are in the 4d subshell? 2. How many electrons are in the 4d subshell of the Molybdenum (III) ion?

Chemistry
What would be the effect on Ksp if an unsaturated solution of CaSO4 was titrated instead of a saturated solution of CaSO4. would ksp be higher, lower or the same? would ksp be higher due to the more ions available in the solution. so you would have to use more titrant to equal...

chemistry
How many phases and components are present in a saturated solution of Na2so4 with excess of solid is present at equilibrium with its vapour in a closed vessel

CHEMISTRY
What is the root-means square speed of Sulfur Dioxide gas at 345.0K?

chemistry
3a.How many electrons are predicted to be in the 4p orbital of a bromine (Br) atom? 5 b.How many of these electrons are predicted to be unpaired? 5

Chemistry
If 42 mL of Cr2O7-2(aq) solution is titrated to the endpoint with 172 mL of 0.15 M Cl-, what was the concentation of Cr2O7-2 solution? I got the reaction 14 H+(aq) _ Cr2O7-2(aq) + 6 Cl- = 2 Cr+3(aq) + 3 Cl2(g) + 7 H20(l) Now I have drawn a blank. Please help!

chemistry
If 35 mL of H2SO4 is titrated to the equivalent pint with 45 mL of 0.30M NaOH, what is the molarity of the H2SO4 before and after the reaction?

chemistry
If you titrated 50 mL of HCl and 50 mL H2SO4, each of the same molarity, with NaOH. What is the numerical ratio of the volume of NaOH required for HCl compared to that for H2SO4?

chemistry
Carbon dioxide gas is predicted to diffuse _______ times faster than sulfur dioxide gas under the same conditions.

chemistry
In the predicted electron configuration of Molybdenum (Mo), how many electrons are in the 4d subshell? 2. How many electrons are in the 4d subshell of the Molybdenum (III) ion?

Chemistry
An electron is in the 5f orbital. What are the values or sets of values for… a. The principle quantum number (n)? b. The angular momentum quantum number (l)? c. The magnetic quantum number (ml)?

college chemistry
The equilibrium constant for the reaction Sr(s) + Mg2+(aq) <---> Sr2+(aq) +Mg(s) is 3.69 x 10^17 at 25 C. Calculate Ecell for a cell made up of Sr/Sr2+ and Mg/Mg2+ half cells.

chemistry
why photosynthesis is considered as endothermic?

Chemistry
Use the data in the table to calculate the equilibrium constant for the following reaction. HCOOH(aq)+ OH −(aq) equilibrium reaction arrow HCOO−(aq)+ H2O(l) HCOO is 5.9e-11 (Kb) HCOOH is 1.7e-4 (Ka) Not sure how to find the equilibrium constant given this information

Chemistry
If 2.5x10^-3 moles of O2 were produced in the reaction, how many grams of H2O2 had to react?

physics/chemistry:sir steve drbob222 steve steve
A crystal is grown by evaporating A and 8 type atoms, and then letting them condense to form the crystal. If, because of the forces involved, on A atom is twice as likely to stick to the crystal OS a B atom, what is the probability that the final crysta pls show step i dont know

Chemistry
Oxalic acid , HOOCCOOH (aq) , is a diprotic acid with Ka1= 0.0560 and Ka2=0.0145. Determine the [-OOCCOO-] in a solution with an initial concentration of 0.139 M oxalic acid. HOOCCOOH(aq) = HOOCCOO-(aq) + H+(aq) HOOCCOO-(aq) = -OOCCOO-(aq) + H+(aq) I have tried a ICE diagram: ...

Chemistry
Oxalic acid , HOOCCOOH (aq) , is a diprotic acid with Ka1= 0.0560 and Ka2=0.0145. Determine the [-OOCCOO-] in a solution with an initial concentration of 0.139 M oxalic acid. HOOCCOOH(aq) = HOOCCOO-(aq) + H+(aq) HOOCCOO-(aq) = -OOCCOO-(aq) + H+(aq) I have tried a ICE diagram: ...

Chemistry
how much energy is released during the reaction of 2.5l diboron hexahydride with 5.65l chlorine gas?

Chemistry
How much heat is required to raise the temperature of 25g of aluminum from 25.0 C to 100 C? Convert this value to joules?

Chemistry
35.0mL of 0.050 M HCl is titrated with 0.050 M NH3 (Kb= 1.8 x 10^-5). The pH of the analyte solution after 15.0mL addition of NH3 titrant is?

Chemistry
A gas diffuses 3.98 times slower than H2 at the same temperature and pressure. What is the molar mass of the gas?

Chemistry
Please someone explain the best way of solving this. A 55 kg woman has 7.5 x 10 to the power of negative 3 moles of hemoglobin (Molar mass=64,456 g/mole) in her blood, how many hemoglobin molecules is that? What is the quantity in grams?

Chemistry
Calculate the mass f CaCo3, in Kg, needed to slurry to extract the SO2 present in 10m3 of industrial waste gases at rtp, if SO2 comprises 10% of this volume.

Chemistry
Identify the acid-base pairs in the following reactions HSO4^1-(aq) + OH^1- <==>SO4^2-(aq) + H2)(I)

Chemistry
1. The decomposition of acetaldehyde is a second order reaction with a rate constant of 4.71 × 10^−8 L/mol/s. What is the instantaneous rate of decomposition of acetaldehyde in a solution with a concentration of 5.55 × 10^−4 M? 2. The rate constant for the first-order ...

Chemistry
What is the pH of the solution if 0.015 mol of HCl is added to a buffer containing 0.014 mol of RCOOH and 0.033 mol of RCOONa (source of RCOO-)? Ka = 2.8E-5 I have tried the following: adding 0.014 + 0.015 = 0.029 ph = pka + log (Base/Acid) pH = -log(2.8E-5) + log(0.033/0.029...

Chemistry
heating cyclopropane (C3H6) converts it to propene (CH2=CHCH3). The rate law is first order in cyclopopane. If the rate constant at a particular temp is 6.22x10^-4 s^1 and the concentration of cyclopropane is held at .0300 mol/L, what mass of propene is produced in 10.0 min in...

Chemistry
Arrange the following cations in order of decreasing size :Ra2+,Sr2+,Ca2+,Ba2+.Also explain it.

Chemistry
what volume of carbon dioxide is produced when 49.7g of calcium carbonate reacts completely according to the following reaction at 25C and 1atm? 25C=298K R= 8.31441 J K-1 mol-1 101325 x V= 49.7x8.31441x298 V= 49.7x8.31441x298 101325 =1.2153 m3 Please help am I even on the ...

Chemistry
How many liters of CO2 would be collected over water from the bomcustion of 35g of cyclohexane, if the gas is collected at a barometric pressure of 765 torr and a temperature of 303 K?

Chemistry
Which type of polyethylene has no side chains? A) LLDPE*** B) HDPE

Chemistry 151
Calculate the concentration in g/dm3 of HNO3 in solution A. (H=1; N=14; O=16; Na=23)

chemistry
(b) (i)The e.m.f. of the cell was measured as 0.62 volts. Taking the standard electrode potential of Cu/Cu2+ as = +0.34 volts, calculate the standard potential of the Co/Co2+ system. Be careful to indicate whether your answer is positive or negative. (ii) State the direction ...

chemistry
calculate the molality of a solution that has 1.02kg sucrose C12H22O11 dissolved in 554g water?

chemistry
What is the molality of a solution composed of 25ml og toluene C6H5CH3 ( density=0.866g/ml) in 75 ml of benzene ( density=0.879g/ml)

Chemistry
A 10 g sample of water at 24 Celsius is mixed with 30.0 g of water at 48 Celsius. Calculate the final temperature of the mixture assuming no heat loss to the surroundings. The specific heat of water is 4.18 j/g•C

Chemistry
A dye has a λmax = 460 nm (ε = 70,000 L/(mol*cm)). What is the concentration of dye in a sample whose absorbance at 460 nm is A = 0.350 in a cell with a path length of 1.00 cm (4 points) I have no idea how to do this.

chemistry
2KCLO3+heat makes 2KCL+3O2 is it endothermic or exothermic

2017 chemistry practical
the titre I am obtaining in the titration of hydrochloric acid against sodium trioxocarbonate (iv) decahydrate is out of range.(42.40cm3). How should I go about it?

Chemistry
C4H6O2 a) Draw a plausible structure for this compound that contains alcohol, ether, and alkyne functional groups. b) Draw a plausible structure for this compound that contains aldehyde and ketone functional groups.

Chemistry
Indicate which elements can be used as potential semiconductors, and which ones can be used as potential dopants used to make n-type and p-type semiconductors by placing them in the corresponding bin. F, Al, As, Ge, I. p-type semiconductors can consist of: a)highly purified ...

Chemistry
If I have 42g of NaCl how many moles of NaCl do i have?

Chemistry
In a coffee cup calorimeter, 2.00 g of potassium hydroxide are mixed with 200.0 g of water at an initial temperature of 25.00C. After dissolving the salt, the final temperature of the solution is 27.33C. What is the heat change for the dissolution of potassium hydroxide ...

Chemistry
Thirty feet of water exert a pressure of 1 atm. Calculate the pressure (in kPa) exerted on a diver at a depth of 50 feet on a standard day.

Chemistry
A 30 g sample of water at 280 K is mixed with 50 g water at 330 K. Calculate the final temperature of the mixture assuming no heat loss to the surroundings.

chemistry
A 3.04 g piece of aluminum at 60.0 °C is placed into a “styrofoam cup” calorimeter filled with 150.0 mL of water at 25.0 °C. What is the final temperature of the contents of the calorimeter once thermal equilibrium has been established (everything has the same final ...

Chemistry
What is the subshell designation for an electron with the following set quantum numbers? 1) n = 1; l = 0 2) n = 3; l = 2; mi = -1 3) n = 4; l = 3 3) n = 2; l = 0; mi = 0

Chemistry
How many orbitals are available with the following combination of quantum numbers? 1) n = 2; l = 0 2) n = 3; l = 2 3) n = 4; l = 3 I have figured that it is 1) 2s 2) 3d 3) 4f but i don't know what to do after this.

Chemistry
How many different f orbitals are there?

Chemistry
A metal foil has a threshold frequency of 5.45 x 10^14 Hz. Which color of visible light will not eject electrons from this metal? a) blue b) indigo c) violet d) orange c=(wavelength)(v) 3.0x10^8m/s = (wavelength)(5.45 x 10^14 Hz) 550 nm -> releases green. So, I am guessing ...

Chemistry
A 32 W (1 W = 1 J/s) lamp generates violet light at a wavelength of 420 nm. How many photons of this light will the lamp generate in 2.0 s?

Organic Chemistry
If one gram of aspirin is dissolved in 100mL of water at 37 degrees celsius, how much aspirin will precipitate out of solution when it is cooled to 25 degrees celsius?

Chemistry
Will a photon of light of wavelength 480 nm excite an electron in the hydrogen atom from the n = 1 level to the n = 2 level? How would I figure this out?

chemistry
2NO2(g)⇌N2O4(g). ΔH∘f for N2O4(g) is 9.16 kJ/mol.

Chemistry
An electron initially in the n = 2 energy level in a hydrogen atom absorbs a photon of light with a frequency of 6.167 x 1014 s-1. Calculate the new energy level the electron will occupy. I am not sure how to being.

chemistry
what is 1.79 x 10^-20 in kJ/mol?

chemistry
It takes 445.76 J of heat to increase the temperature of a 50.0 g piece of metal from 20.0 °C to 65.0 °C. What is the specific heat capacity of the metal (assuming the phase doesn\'t change)? Also please show work

Chemistry Heat
4Fe + 3O2 ---> 2Fe2O3 Delta H -1652 kJ How much heat is released when 10 g Fe and 2 g O2 are reacted.

Chemistry
So Ag+ + Cl- ---> AgCl and delta H is -65.5 kJ. I'm supposed to calculate delta H when one mole of AgCl dissolved in water, so 1 mol AgCl *(65.5 kJ/1mol Agcl) right? But the answer is 65.5 kJ, and why is it positive, not negative, is my question.

Chemistry
The reaction Fe + Br2 ---> FeBr2 Delta H = -249.8kJ Calculate delta H when 10.0 g of FeBr2 is formed.

CHEMISTRY
How many liters of chlorine gas at 25C and 0.950 atm can be produced by the reaction of 24.0 g of MnO2 with hydrochloric acid? The products include manganese (II) Chloride, water, and chlorine.

Chemistry
I am completely lost with this question. If 50 ml of 0.5M HCl is added to 800 ml of pure water, what will be the approximate pH of the resulting solution?

Chemistry
You want to make 40 mL of gas from some aluminum carbonate. The temperature of the lab is 23 C and the rpessure is 760 torr. If you collect the gas over water, what mass of reactant is necessary?

Chemistry
What volume of gas can be produced in a lab where pressure is 16.0 psi and temperature is 25 C if you collect it over water from the reaction of 50g of ammonium sulfate with 50g of aluminum hydroxide. The equation for the reaction is: 3(NH4)2SO4 + 2Al(OH)3 ---> Al2(SO4)3 + ...

Chemistry
What mass of zinc would need to react with hydrochloric acid in order to produce 25.0 mL of hydrogen gas collected over water at 25 degrees celsius and 105 kPa. How do you solve this using the combined gas laws? The answer is 0.067 grams but how do you get there?

Chemistry
calculate the volume occupied by 7g of N2 gas at 27 degree c and 750mm Hg pressure

Chemistry
Consider two flasks. What are the final partial pressure of H2 and N2 after the stopcock between the two flasks is opened? Assume the final volume is 3.00 L. What is the total pressure in torr? Flask 1: 2.00 L H2, 475 torr Flask 2: 1.00 L N2, 0.200 atm Imagine two round flasks...

chemistry
A balloon is filled with hydrogen gas. reaction is Fe(s) + H2SO4(aq) ----> FeSO4(aq) + H2(g). The volume of the ballon was 4800 m cubed and the loss of hydrogen gas during filling was estimated at 20.% What mass of iron splints and 98% by mass H2SO4 were needed to ensure ...

chemistry
A researcher put 10.0 moles of N2O into a 2-L container at some temperature where it decomposes according to the following: N2O = 2N2+ O2. At equilibrium 2.20 moles of N2O remain. Calculate the Kc for the reaction. How am I supposed to fill in the ICE chart if Kc isn't given ...

Chemistry
What volume will 11.2 grams of H2 gas occupy at 25.1oC and a pressure of 758 mmHg?

Chemistry please help!
Calculate (triangle)H for the following gas-phase reaction: 2 H-C (3dashes) C-H + 5 O=O --> 4 O=C=O = 2 H-O-H -Using bond energies

Chemistry Homework
Hello! Could someone help me with this? I'm confused on what to do. Thanks!! The mole fraction of carbon dioxide (CO2) in water is 0.25. Determine the molarity of CO2. The density of the solution is 1.0 g/mL.

chemistry
what is the % (m/m) of Mg(NO3)2 in solution when 0.84 g of Mg(NO3)2 are dissolved in enough deionized water to prepare 500.0 ml of solution ( assume the solution in dilute enough that the density of the solution is 1.0 g/ml)

Chemistry
What will be the final temp. of the solution in a coffee cip calorimeter if a 50.00mL sample of 0.250 M HCL is added to a 50.00 mL sample of 0.250. The initial temp. is 19.50 °C and the Delta H is -57.2 Kj/mol NaOH assume density of solution is 1.00 g/mL and specific heat of ...

Chemistry
Aluminum is produced by the electrolysis of aluminum oxide (Al2O3, bauxite ore) dissolved in molten cryolyte (Na2AlF6). Calculate the mass of aluminum that can be produced in one day in an electrolytic cell operating continuously at 1.0 x 105 amps. The cryolite does not react

MATH
Jenny is running an experiment for organic chemistry class. She needs exactly 100 ml of 70% hydrochloric acid, but the lab only has 90% and 40% solutions. How much of each solutions does she need to mix in order to obtain 100 ml of 70% hydrochloric acid solution?

chemistry
Draw a well diagram of the set up of the aparatus that can be used to show that ammonia gas can burn in oxygen Write the equation for combustion of ammonia In oxygen PLEASE HELP MI TO ANSWER THAT QUESTION IT DEFEATED MI

Chemistry
The functional group contained in the compound O || CH_3-C-O-CH_3 is a(n). A)carboxy B)amine C)ester D)amide

Chemistry
The equilibrium constant is equal to 5.00 at 1300K for the reaction 2SO2(g) + O2(g) <--> 2SO3(g) if initial concentrations are [SO2] = 6.00M, [O2] = 0.45M, [SO3]= 9.00M, the system is a/. At equilibrium b/. Not at equilibrium and will remain in an un equilibrated state c...

chemistry
How many milliliters of an aqueous solution of 0.238 M magnesium bromide is needed to obtain 9.01 grams of the salt?

Chemistry
Assume you are performing the calibration step and you begin with 70 g of water at 20*C and 70 g of water at 80*C. After adding the two portions of water into your calorimeter setup and following the procedure outlined in the experiment, you determine the temperature of the ...

Chemistry
Consider the following decomposition reaction of ammonium carbonate ((NH4)2CO3): (NH4)2CO3 (s)  2 NH3 (g) + CO2 (g) + H2O (g) In one experiment at 25.0°C, a sample of pure (NH4)2CO3 is placed in an evacuated 2.00 L vessel. At equilibrium, the total pressure is found to be ...

Chemistry
PLEASE HELP! Consider the following galvanic cell: Ag(s) | Ag+(aq) || Cu2+(aq) | Cu(s)? Match the components with their function in the cell. 1. | 2. || 3. Ag(s) | Ag+(aq) 4. Cu2+(aq) | Cu(s) A. Cathode Half Reaction B. Phase boundary C. Salt Bridge D. Anode Half Reaction

Chemistry
For the galvanic cell that uses the reaction 2 Al(s) + 3 Ni2+(aq) → 2 Al3+(aq) + 3 Ni(s) the value of n in the relationship ΔG° = -nFE° is ________.

chemistry
Calcium is determined gravimetrically by precipitating it as CaC2O4â‹… H2O, followed by isolating the precipitate as CaCO3. The sample to be analyzed is dissolved in 10 mL of water and 15 mL of 6 M HCl. After dissolution, the resulting solution is heated 24 to boiling, ...

chemistry
Aluminum can be determined gravimetrically by precipitating as Al(OH)3 and isolating as Al2O3. A sample containing approximately 0.1 g of Al is dissolved in 200 mL of H2O and 5 g of NH4Cl and a few drops of methyl red indicator is added (methyl red is red at pH levels below 4 ...

science (chemistry)
consider the following reaction AgNO3+KBr=AgBr+KNO3 calculate the amount of presipitate in gram obtained when 0.25 mole of AgNO3 is trheated with excess of aqueous KBr solution

Chemistry
Nitrogen monoxide reacts with chlorine gas according to the reaction: 2NO (g) + Cl2 (g) ⇔ 2NOCl (g) Kp = 0.27 at 700 K A reaction mixture initially contains equal partial pressures of NO and Cl2 . At equilibrium, the partial pressure of NOCl is 115 torr. What were the ...

chemistry
So we did an experiment where we mixed Cacl2 and NaCl and then found the mass of the precipitate. Then we compared it to reference data on a standard curve to see the mass of Na2Co3 reacting to produce the CaCo3. So what I'm stuck on is this: Suppose the precipitate formed in ...

Chemistry
What is the Pb2+ concentration in a saturated solution of PbCl2 if the concentration of chloride ion is 0.023 M? Units: M ksp = 1.72x10^-5 i can't seem to get the answer. i have tried and ICE diagram and going from there: PbCl2 (s) <--> Pb ^2+ = 2Cl- I: 0.023 M = Cl- C: ...

Chemistry
Please help. I have tried this a few different times and have come up with the same answer. What is the pH of the solution if 0.01 of HCl is added to a buffer containing 0.013 mol of RCOOH and 0.035 mol of RCOONa (source of RCOO-)? Ka = 2.7E-5 so far i have tried the following...

Chemistry
I'm not sure how to do these and when I looked it up, maybe there was a diff. vocab used. Please help! 1.) How do you do atom/ion inventory of : Cu3(PO4)2 A. _____ formula units Cu3(PO4)2 B. _____ atoms Cu C. _____ atoms P D. _____ atoms O E. _____ ions Cu2+ F. _____ ions PO43...

Chemistry
How many moles of benzoic acid, a monoprotic acid with Ka=6.4×10^-5, must dissolve in 250mL of H2O to produce a solution with pH=2.04

Chemistry
The Ksp for Fe(OH)3 is 1.6x10-39. Calculate the concentration of OH- if the concentration of Fe3+ at equilibrium is 0.0050M in an aqueous saturated solution of Iron(III)hydroxide.

chemistry
how can I calculate the limiting reactor in a reaction?

Chemistry
How many moles of Fe(OH)2 will dissolve in 1.00L of water buffered at pH = 12.00? Fe(OH)2 has Ksp = 1.8 × 10^-15. How would I do this? Should I make an ice table? I know the pOH = 2.00.

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