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February 8, 2016

Homework Help: Science: Chemistry

Recent Homework Questions About Chemistry

Chemistry
Can you please explain to me how you would regulate the pressure to favor the products in the this equilibrium system. MgCO3(s)--><-- MgO(s)+CO2(g)
Tuesday, August 11, 2015 by coco

Chemistry
A buffer solution A. contains approximately equal amounts of a weak acid and its conjugate base. B. increases its properties with an increase in the concentrations of the two buffer components. C. resists changes in pH. D. all of the above This one is D right
Tuesday, August 11, 2015 by Lili

Chemistry
All Brønsted-Lowry acids A. are aqueous solutions. B. can act as Arrhenius acids. C. donate protons. D. all of the above I think it is D, but I also think it is c can you please tell me if either of these answers are right thanks
Tuesday, August 11, 2015 by Lola

Chemistry
All Brønsted-Lowry acids A. are aqueous solutions. B. can act as Arrhenius acids. C. donate protons. D. all of the above I am a little confused. I think it is D, but I'm second guessing myself with C
Tuesday, August 11, 2015 by Lola

Chemistry
Can you please explain to me how you would regulate the pressure to favor the products in the this equilibrium system. MgCO3(s)--><-- MgO(s)+CO2(g) Thank you
Tuesday, August 11, 2015 by Sydney

Chemistry
Can you please explain to me how you would regulate the pressure to favor the products in the this equilibrium system. MgCO3(s)--><-- MgO(s)+CO2(g) Thank you
Tuesday, August 11, 2015 by Sydney

Chemistry
if the rate of a certain reaction is 6M/hr at 273K, what would be the predicted rate at 278k with activation 30kj/mol
Tuesday, August 11, 2015 by Anonymous

nsikayethu secondary comprehensive school
physical science (chemistry).place them in order Which liquid will evaporates faster between ethanol, nail porish remover, methylated spirits and water
Tuesday, August 11, 2015 by snenhlanhla

Chemistry
The following reaction represent a propsed reaction mechanism for the formation C(C6H5)3OH from C(C6H3)3Cl. Step 1: C(C6H5)3Cl--> C(C6H5)3^+ + Cl- Step 2: C(C6H5)3^+ + OH- --> C(C6H5)3OH What are the intermediate product(s) of the net reaction? Explain your answer. So I ...
Monday, August 10, 2015 by Jake

Chemistry
An organic compound x contains 40% carbon, 6.7% hydrogen the third compound oxygen. If the relative molecular mass of the compound is 60, calculate (i) the empirical formular of x (ii) the molecular formular of x
Monday, August 10, 2015 by Akighir Reuben

Chemistry
I want to make 10 ml solution of 80% NaOH and 20% KOH
Monday, August 10, 2015 by Pratyush

chemistry
can you please explain to me why a common ion lowers the solubility of an ionic compound
Monday, August 10, 2015 by sydney

chemistry
By applying Le Châtelier’s principle to a reaction that has come to equilibrium, the reaction can be made to A. produce more reactants. B. run to completion. C. reach a new chemical equilibrium. D. All of the above Is the answer D?
Sunday, August 9, 2015 by syd

Chemistry
Before a chemical reaction reaches equilibrium, A. the reaction rates of the reactants and products increase. B. the reaction rate of the reactants increases and the reaction rate of the products decreases. C. the reaction rates of the reactants and products decrease. D. the ...
Sunday, August 9, 2015 by soco

Chemistry
Which processes are taking place in the following reaction? 2CO(g) + O2(g) ⇌ 2CO2(g) A. displacement and reduction B. synthesis and decomposition C. ionization and recombination D. sublimation and evaporation Is B right?
Sunday, August 9, 2015 by Coco

Chemistry
The following reaction represent a propsed reaction mechanism for the formation C(C6H5)3OH from C(C6H3)3Cl. Step 1: C(C6H5)3Cl--> C(C6H5)3^+ + Cl- Step 2: C(C6H5)3^+ + OH- --> C(C6H5)3OH What are the intermediate product(s) of the net reaction? Explain your answer. What ...
Sunday, August 9, 2015 by jonah

chemistry
Standard Addition Question: Serum containing Na+ gave a signal of 4.27 mV in an atomic emission analysis. Then 5.00 mL of 2.08 M NaCl were added to 95.0 mL of serum. This spiked serum gave a signal of 7.98 mV. Find the original concentration of Na+ in the serum. I can't ...
Sunday, August 9, 2015 by Phil

Chemistry
The student used the KHP in a subsequent titration experiment where he titrated 25.00 +/- 0.03 ml of the acid against an unknown solution of NaOH. The titration required 23.70 +/- 0.10 ml of the base. What is the concentration of NaOH?
Sunday, August 9, 2015 by Aaeisha

Important question regarding chemistry
Explain intermolecular hydrogen bonding with reference to ortho nitrophenol
Saturday, August 8, 2015 by Sonam

Chemistry
I'm having trouble understanding rate laws and manipulating them. So, for example, the rate law is rate= k[CO2][O3]. I was taught, maybe if I am just forgetting some pieces(been awhile), if I were to triple/double the partial pressure of CO2/O3, the rate of that element ...
Friday, August 7, 2015 by Jake

Chemistry
Radioactive decay is first order in the decaying isotope. For example, strontium-90 contained in fallout from nuclear explosions decays to yttrium-90 and a beta particle. Write the rate law for the decay of strontium-90. Can you please take me step by stem through this problem?
Friday, August 7, 2015 by Soco

Chemistry
what information must you know to calculate the boiling point elevation of a solution of hexane in benzene. Is it the temp, Kb and the molality?
Friday, August 7, 2015 by Coco

Chemistry
heating cyclopropane (C3H6) converts it to propane (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 propane is produced in 10.0 min in...
Friday, August 7, 2015 by Coco

Chemistry
Use the data in the table to determine how long it will take for half of the original amount of SO2Cl2 to decompose at the average reaction rate. Experimental Data for SO2Cl2(g) → SO2(g) + Cl2(g) Time (min) [SO2Cl2](M) [SO2](M) [Cl2](M) 0.0 1.00 0.00 0.00 100.0 0.87 0.13...
Friday, August 7, 2015 by Chloe

chemistry
suppose that a large volume of 3% hydrogen peroxide decomposes to produce 12mL of oxygen gas in 100 s at 298 K. Estimate how much oxygen gas would be produced by and identical solution in 100s at 308 K hi can you please help me set up this problem, then I can do the math, I ...
Thursday, August 6, 2015 by Chloe

chemistry
Calculate the molality of the solution prepared by dissolving 0.50 g (NH4)2SO4 in 50g H2O
Thursday, August 6, 2015 by amy

Chemistry
The rate law for the reaction NO + O3 > NO2 is rate= k[NO][O3]. What will the effect on the reaction rate if the partial pressure of NO is doubled? What will the effect if the partial pressure of O2 is tripled? Just for clarification: NO will be doubled and O3 would be ...
Thursday, August 6, 2015 by Liane

Opra college
Chemistry work........the volume of oxygen measured at stp will br produced on heating 24.5grams of potassium trioxochlorate(v)
Thursday, August 6, 2015 by Pelumi

Chemistry
Predict whether each of the following reactions would be spontaneous or non spontaneous under standard conditions or if it is impossible to tell with the data given. a)2KClO3(s)+3C(s)-->3CO2(g)+2KCl(s) Exothermic b) 2NO(g) + O2(g) ---> 2NO2(g) Exothermic c)H2(g)+Zn(ClO3)...
Thursday, August 6, 2015 by Ferb

DPS sub: science ( chemistry)
an element 'x' react with water to form a solution which turns phenolphthalein indicator pink .The element 'x' is most likely a) sulphur b) sodium c) carbon d) silicon
Thursday, August 6, 2015 by kristi

chemistry
Calculate the pH at the equivalence point in titrating 0.110 M solutions of each of the following with 8.0×10−2 MNaOH. Part A hydrobromic acid (HBr)
Thursday, August 6, 2015 by Anonymous

Chemistry
What is the balanced equation of reaction between glacial acid, benzoic acid and sodium hydrogen carbonate solution
Thursday, August 6, 2015 by Realone

chemistry
Why is filter paper a poor material on which to powder a solid before introducing it into a melting tube?
Thursday, August 6, 2015 by charlotte

Chemistry
What data do you need to determine whether the following reaction is spontaneous or not? 4Fe(s) + O2(g) ----> 2Fe2O2(s) Would it be temperature, delta H and delta S?
Wednesday, August 5, 2015 by Sharkeisha

Chemistry
If there are 5,280 ft=1.00 mile ,how many miles are in 50,000 ft?
Wednesday, August 5, 2015 by Lara

Chemistry
If the speed of light is 186,000 miles / sec, how far does light travel in 8.0 minutes?
Wednesday, August 5, 2015 by Sara

Chemistry(Titration)
Why is methyl orange indicator used instead of phenolpthalein when determing calcium content in a chalk by back titration
Wednesday, August 5, 2015 by Kester

college. physics and chemistry and mathematics
An element crystalline in face centred cubic lattice. CCalculate the length of the side of the unit cell if the radius of atom is200pm
Wednesday, August 5, 2015 by nerswn narzary

chemistry
What is the pH of a buffer solution if you have 250 ml of a 1.56M Acetic Acid and you added 26.56 grams of sodium acetate (NaCH3CO2)? What is the new pH if you now add 1gram of NaOH to the buffer solution?
Wednesday, August 5, 2015 by lilly

Chemistry
Determine the mass of PbSO4 produced when 10mL of 0.2M CuSO4 reacts with 10mL of 0.2M Pb(NO3)2? Balance the equation CuSO4 + Pb(NO3)2 → PbSO4 + Cu(NO3)2 Find the number of moles for CuSO4 c=n/v n=c × v n=0.2 × 0.01 n=0.002 mol Since it is a 1:1 ratio, the ...
Wednesday, August 5, 2015 by Kendall

Chemistry
What is the sign of the entropy change for the following reaction, which is the principal process taking place when mortar hardens? Ca(OH)2(s) + CO2(g) ---> CaCO3(s) + H2O(l) Would the sign of entropy be negative since a solid and gas yields a solid and what does it mean by...
Tuesday, August 4, 2015 by D

college chemistry
The air in a typical La Crosse basement contains 53 atoms of 222Rn per liter. A. If the basement has 950 ft^2 of floor space and is 8.0 feet tall, how many 222Rn atoms are there in the whole basement? B. Assuming a total pressure of 1.00 atm, what is the partial pressure of ...
Tuesday, August 4, 2015 by Sara

college chemistry
A piece of wood is discovered in the Amazon with a 14C/12C that is 64.3% that of living organisms. How old is it? I have no clue how to do this please help.
Tuesday, August 4, 2015 by Sam

Chemistry
In this reaction solid NaOH is added to approximately 100 mL of 0.500 mol/L HCl. Trial 1: 2.02 g of solid NaOH is added to 102.0 mL of the HCl solution. The temperature goes from 22.00°C to 32.0°C. Calculate the heat evolved in each trial (Q). I'm confused on how ...
Tuesday, August 4, 2015 by Emily

Urgent Chemistry
The diffusion current for a standard is 1 x 10^-4M solution of hydroquinone is 17.5 microamperes. An unknown solution of hydroquinone, when diluted hundred folds and polarographed under same conditions yielded a current of 30.5 microamperes. Calculate the concentration of ...
Tuesday, August 4, 2015 by Adeola

chemistry
What are the uses of azomethine?
Tuesday, August 4, 2015 by Edward

URGENT CHEMISTRY
1. Write the equilibrium expressions for the following reactions: a) 2 N2O(g) + O2(g)  4 NO(g) b) H2(g) + CO2(g)  H2O(g) + CO(g) c) 4 HCl(g) + O2(g)  2 Cl2(g) + 2 H2O(g) d) 3 H2(g) + N2(g)  2 NH3(g) e) H2(g) + Cl2...
Tuesday, August 4, 2015 by Michael

Chemistry
I really need help with this I am really confused with the law, I have looked at multiple examples and I am still so confused, I know you can't give me the answer, but is there anyway you could please take me through this question step by step? Use Hess's law and ...
Tuesday, August 4, 2015 by Chloe

Chemistry
The percent is confusing me, can you please help me set this equation up. How much heat is liberated when 5.00 kg of coal is burned if the coal is 96.2% carbon by mass and the other materials in the coal do not react? (delta)H comb of carbon is -394kJ/mol thank you
Monday, August 3, 2015 by Syd

chemistry
Please tell me any website....where I can find details of the experiment Reaction of 4-aminotoluene and o-vanillin(for preparation of azomethine)
Monday, August 3, 2015 by Edward

Chemistry
Water is sprayed on oranges during a frosty night. If an average of 11.8 g of water freezes on each orange how much heat is released. Can you please help me set this problem up. I don know what formula to use? thank you
Monday, August 3, 2015 by SS

chemistry
Could you please tell me the objective, theory and mechanism,result, precautions and applications of following experiment : reaction of 4-aminotoluene and o-vanillin(preparation of azomethine)
Monday, August 3, 2015 by Edward

Chemistry
Can you please help me with this problem, I am so confused, and I do not know how to set it up, what equation to use, and what do i need to convert. 1 Transportation Ethanol is being used as an additive to gasoline. The combustion of 1 mol of ethanol releases 1367kJ of energy...
Monday, August 3, 2015 by Syd

Urgent chemistry
Given the following reaction: 3 H2(g) + N2(g) <- -> 2NH3(g) + heat If the following changes were to occur what direction shift will it have (left or right) And what will be the reason of the shift Changes/Stress on system: Decreasing the pressure Adding heat Removing N2
Monday, August 3, 2015 by Nathaly hernandez

NURSING ASAP
Is nursing considered a a science major because I'm taking this course called "CHEM 1001 Chemistry and the World Around Us?" and I studying nursing in college. Please be honest. Thank you! :)
Monday, August 3, 2015 by Sam

Chemistry
1)During an endothermic reaction, total energy A. decreases. B. increases. C. stays the same. D. cannot be determined. 2)The enthalpy of formation of an element is A. negative. B. positive. C. zero. D. negative or positive, depending on which element. i think number 1 is A for...
Monday, August 3, 2015 by Anonymous

Chemistry
Any student is welcome to use this for extra practice and anyone is welcomed to amswed the question. Here is a couple of practice problems a) 2 N2O(g) + O2(g)  4 NO(g) B) H2(g) + CO2(g)  H2O(g) + CO(g) C) 4 HCl(g) + O2(g)  2 Cl2(...
Monday, August 3, 2015 by Cole williams

Chemistry
Given the following reaction: 3 H2(g) + N2(g) <- -> 2NH3(g) + heat If the following changes were to occur what direction shift will it have (left or right) And what will be the reason of the shift Changes/Stress on system: Adding NH3 Decreasing the pressure Adding heat ...
Monday, August 3, 2015 by Sarah foster

Chemistry
Given the following reaction: 3 H2(g) + N2(g) <- -> 2NH3(g) + heat If the following changes were to occur what direction shift will it have (left or right) And what will be the reason of the shift Changes/Stress on system: Adding NH3 Decreasing the pressure Adding heat ...
Monday, August 3, 2015 by Sarah foster

Chemistry
1.00g of oxygen combine with 0.126 g of hydrogen to form H2O. 1.00 g of nitrogen combie with 0.216 g of hydrogen to form ammonia. Predict the weight of oxygen required to combine with 1.00 g nitrogen to form an oxide.i m a student
Monday, August 3, 2015 by Rao

Chemistry
1.00g of oxygen combine with 0.126 g of hydrogen to form H2O. 1.00 g of nitrogen combie with 0.216 g of hydrogen to form ammonia. Predict the weight of oxygen required to combine with 1.00 g nitrogen to form an oxide.
Monday, August 3, 2015 by Rao

Chemistry
In a constant-pressure calorimeter, 65.0 mL of 0.330 M Ba(OH)2 was added to 65.0 mL of 0.660 M HCl. The reaction caused the temperature of the solution to rise from 24.28 °C to 28.78 °C. If the solution has the same density and specific heat as water, what is ΔH ...
Sunday, August 2, 2015 by Emily

chemistry
calculate the mole fraction of ethylene glycol in a solution containing 20% of ethylene glycol prepared in water. answer it as fast as possible.........
Sunday, August 2, 2015 by raksha

Chemistry
How many moles of Ag2CrO4 will be produced from 6 moles of AgNO3?
Saturday, August 1, 2015 by Andrea

Chemistry
Explain why a catalyst speeds up a chemical reaction.
Saturday, August 1, 2015 by Tais

chemistry
If 25ml of 3M HNO3 AND 75ml of 4M HNO3 ar
Saturday, August 1, 2015 by murtaza

Organic chemistry
What type of alcohol is used in the production of alcoholic beverages?
Saturday, August 1, 2015 by Kester

Chemistry
What is the correct order of increasing acidity of the following acids;HF,HI,HCl,HClO4 and HBr.
Saturday, August 1, 2015 by Anonymous

Chemistry
A sample of nitric acid has a density of 1.42g/cm3 and contains 69.5% by weight of the pure acid.What is the molarity of the solution?
Saturday, August 1, 2015 by Kester

Chemistry extra tips
What is the correct IUPAC name for the following 2 compounds? Compund 1) MnO3 Compund 2) N2O Must use a Roman Numeral in name Must use prefixes in name
Friday, July 31, 2015 by Tais

chemistry
HCOOH + CaCO3 will give what (what are the products)
Friday, July 31, 2015 by danielle

Emergency chemistry
PLEASE PLEASE PLEASE ANSWER MY PREVIOUS QUESTIONS
Thursday, July 30, 2015 by Sarah foster

Chemistry
Given the following reaction: XBO3(s) <--> XO(s) + BO2(g) If the concentration of BO2 at equilibrium was 2.0 M, what is the equilibrium constant (K)? Select one: a. Not enough information is given b. 1.0 M c. 2.0 M d. 0.50 M
Thursday, July 30, 2015 by Sarah foster

Chemistry :(
Question text Given the following exothermic, equilibrium reaction: 3 H2(g) + N2(g) <--> 2NH3(g) Using Le Chatelier's Principle, which of the following changes would shift the equilibrium toward more production of NH3? Select one: a. Adding a catalyst b. Adding heat ...
Thursday, July 30, 2015 by Jimmy mendoz

Chemistry
Given the following exothermic, equilibrium reaction: 3 H2(g) + N2(g) <--> 2NH3(g) Using Le Chatelier's Principle, which of the following changes would shift the equilibrium toward more production of NH3?
Thursday, July 30, 2015 by Jimmy mendoz

chemistry
find the mole fraction of 10g/l aquous solution H2So4 having density 0.01 g/ml
Thursday, July 30, 2015 by Hariom

chemistry
A reaction proceeds by the following three-step mechanism with elementary rate coefficients, k. A + B → C k 1 C → A + B k -1 C → B + D k 2 (C is a chemical radical) (ii) By applying the Steady State Approximation determine the overall order of the reaction. (...
Thursday, July 30, 2015 by jay

Chemistry
The formula for magnesium carbonate is MgCO3. What is the charge of the cation in Ag2CO3? Would it be +1 or +2 because there are two of Ag?
Wednesday, July 29, 2015 by Angel

Chemistry
Carbon tetracholoride is made according to the following reaction: carbon disulfide + chlorine gas yields carbon tetrachloride and disulfur dichloride. Write the correct balanced equation and then determine how many grams of CS2 are needed to make 16 kilograms of CCl4. Ok so ...
Tuesday, July 28, 2015 by Dilcia

Chemistry
Carbon tetracholoride is made according to the following reaction: carbon disulfide + chlorine gas yields carbon tetrachloride and disulfur dichloride. Write the correct balanced equation and then determine how many grams of CS2 are needed to make 16 kilograms of CCl4.
Tuesday, July 28, 2015 by Kenneth

Chemistry
Given the balanced equation : 3 CO + 7 H2 -> C3H8 + 3 H2O How much C3H8 will be produced if 45.8 g CO reacts with 87.3 H2 ? Please all your work (i did it but im not sure if i did all the work right)
Tuesday, July 28, 2015 by Dilcia

Chemistry
Carbon tetracholoride is made according to the following reaction: carbon disulfide + chlorine gas yields carbon tetrachloride and disulfur dichloride. Write the correct balanced equation and then determine how many grams of CS2 are needed to make 16 kilograms of CCl4. (...
Tuesday, July 28, 2015 by Dilcia

Chemistry
Determine the concentration at equilibrium if you start with 4.65 grams of Hydrogen and 200 grams of Iodine in a 4.55 liter container. If you now add an extra 1.25M of I2 after equilibrium, calculate Qc. Recalculate now what the concentrations should be at equilibrium. H2(g...
Tuesday, July 28, 2015 by Jessica

chemistry
What is the volume, in L, occupied by 3.260 moles of NO2 gas at STP conditions?
Tuesday, July 28, 2015 by Mindy

chemistry
A fixed amount of CH4 gas occupies a volume of 136 mL at a pressure of 567 mm Hg and a temperature of 19oC. What will be the volume, in mL, occupied by this sample of CH4 gas when the pressure is decreased to 421 mm Hg while holding the temperature constant?
Tuesday, July 28, 2015 by Mindy

chemistry
Consider the following chemical reaction: 2 KNO3 (s) ------------> 2 KNO2 (s) + O2 (g) What volume, in liters, of O2 at 31.2oC and 2.045 atm pressure can be produced from the decomposition of 54.92 g of KNO3 (FM = 101.1 g/mol).
Tuesday, July 28, 2015 by Mindy

chemistry
What is the volume, in L, occupied by 1.20 moles of C2H6 gas at a temperature of 125oC and at a pressure of 1.55 atm?
Tuesday, July 28, 2015 by Mindy

chemistry
A pressurized can of paint contains a fixed mass of gas at an internal pressure of 1.258 atm at 24.8oC. Suppose the can is able to withstand an internal pressure of 2.410 atm before it explodes. At what temperature, in degrees Celsius, will this can explode? HINT: The can is a...
Tuesday, July 28, 2015 by Mindy

chemistry
The combined gas law can be rearranged to solve for T2. In which of the expressions given below has the combined gas law correctly been rearranged to solve for T2?
Tuesday, July 28, 2015 by Mindy

chemistry
The barometric pressure recorded by a weather balloon is 0.731 atmoshperes (atm). Express this barometric pressure in millimeters of mercury (mm Hg).
Tuesday, July 28, 2015 by Mindy

chemistry
Calculate the density of C2H2 gas (FM = 26.04 g/mol), in g/L, at a pressure of 2.082 atm and at a temperature of 62.5oC.
Tuesday, July 28, 2015 by Mindy

chemistry
A 12.8 L sample of Ne gas initially has a temperature of 32.7oC at a pressure of 2.57 atm. What is the new pressure, in atm, if the volume is changed to 10.6 L and the temperature is decreased to 13.9oC?
Tuesday, July 28, 2015 by Mindy

Chemistry
A Mylar Happy Birthday balloon contains 5.15 L of helium gas at 19.4oC. If the pressure remains constant, what will be the volume of helium in the balloon, in L, when the temperature is increased by 6.6oC?
Tuesday, July 28, 2015 by Mindy

Chemistry
A balloon containing 0.600 mole of SO2 gas has a volume of 275 mL at a certain temperature and pressure. What volume, in milliliters, would a 0.765 mole sample of SO2 gas occupy at the same temperature and pressure conditions?
Tuesday, July 28, 2015 by Mindy

Chemistry
A sample of H2 gas occupies a volume of 565 mL at STP. What, volume, in mL, will this sample of H2gas occupy at a temperature of -17oC and at a pressure of 0.560 atm
Tuesday, July 28, 2015 by Mindy

Chemistry
Is 4786 Jules of heat are transferred to 89 g sample of an unknown material within the initial temperature of 23°C what is the specific heat of the material if the final temperature is 89.5 ° C
Tuesday, July 28, 2015 by Dilcia

Chemistry
How many joules of heat when a 640 g piece of copper cools from 375° C to 26° C
Tuesday, July 28, 2015 by Dilcia

Chemistry
How many joules of heat are required to raise the temperature of 550 g of water from 12°C to 18°C
Tuesday, July 28, 2015 by Dilcia

chemistry
The formula for rust can be represented by Fe2O3. How many moles of Fe are present in 24.6 g of the compound? Please guide me through it thank you!
Tuesday, July 28, 2015 by Michelle

AP Chemistry
The formula for rust can be represented by Fe2O3. How many moles of Fe are present in 24.6 g of the compound?
Tuesday, July 28, 2015 by Michelle

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Homework Help: Science