# How many moles are there in a 30 cm diameter basketball at a pressure of 160 kpa and temperature of 25 degree celcius

22,676 questions, page 157
1. ## Chemistry

To what Celsius temperature must 44.5 mL of methane gas at 43.0°C be changed so the volume will be 63.0 mL? Assume the pressure and the amount of gas are held constant. I have already tried T1V1=T2V2

asked by Megan on May 2, 2010
2. ## Physics

A monatomic ideal gas expands from 1.00m^3 to 2.50m^3 st a constant pressure of 2.00x10^5 Pa. Find the change in the internal energy of the gas.

asked by A on November 23, 2012
3. ## Physics

2. The average atmospheric pressure at sea level is approximately 101 000 Pa. If the density of air at 0◦C is approximately 1.3 kg , how high does the atmosphere extend?

asked by Merdreik on October 31, 2016
4. ## literature

i have to write a persuasive essay on obesity, can you just name some problems or diseases that most obese people have: like i know diabetes is one blood pressure (high?) heart problems.... what else?

asked by literature on March 18, 2009
5. ## chemistry

155.0 grams of N2 (nitrogen gas) are put in a 4.50L container at 35C. What is the pressure? PV=nRT n=155/molmassN2 Convert temps to K.

asked by TIFFANY on January 9, 2007
6. ## physics

Use R = 8.2 × 10–5 m3 atm/mol K and NA = 6.02 × 1023 mol–1. The approximate number of air molecules in a 1 m3 volume at room temperature (300 K) and atomospheric pressure is:

asked by sam on June 24, 2009
7. ## Physics

A monatomic ideal gas expands from 1.00m^3 to 2.50m^3 st a constant pressure of 2.00x10^5 Pa. Find the change in the internal energy of the gas.

asked by A on November 22, 2012
8. ## chem

A gas occupying 10 mL at standard conditions is heated to 10◦C while the pressure is reduced to 0.92114 atm. What is the new volume occupied by the gas? Answer in units of mL

asked by a on May 30, 2014
9. ## chem

A reaction yields 0.00704 mol of O2 gas. What volume will the gas occupy if it is collected at 16.0◦C and 0.767 atm pressure? Answer in units of mL

asked by reis on May 30, 2014
10. ## ap chemistry

A sample of gas occupies 4 mL at STP. At what pressure would this sample occupy 500 mL if the temperature is changed to 525C? Answer in units of torr

asked by cheri on February 9, 2013
11. ## Physics

A monatomic ideal gas expands from 1.00m^3 to 2.50m^3 st a constant pressure of 2.00x10^5 Pa. Find the change in the internal energy of the gas.

asked by B on November 24, 2012
12. ## Chemistry

A good vacuum pump on Earth can produce a vacuum with a pressure as low as 1.96 × 10-8 torr. How many molecules are present in each milliliter at a temperature of 23.0ºC?

asked by Hunter on October 28, 2016
13. ## chem

why would it be dangerous to heat a liquid in a distillation apparatus that had no vent or opening to the laboratory? - is this because the liquid will create vapor pressure and could cause a serious injury to a student?

asked by Jason on November 3, 2008
14. ## Chemistry

Consider the decomposition of barium carbonate: BaCO3(s)= BaO(s) + CO2(g). Using data from Appendix C in the textbook, calculate the equilibrium pressure of CO2 at 298K.

asked by Jona on March 31, 2013
15. ## chemistry

c2h4(g) + 3O2(g) -> 2 CO2 (g) + 2 H2O (g) What volume of oxygen will react with 18 ml of ehtylene, c2h4, assuming that the gases are present at the same temperature and pressure?

asked by Monica on April 19, 2010
16. ## science

Urea forms a ideal solution in water. Determine the vapour pressure in an aqua solution containing 10 percent bymass at 40degree Celsius

asked by priya on October 26, 2016
17. ## chemistry

A sample of nitrogen gas has the temperature drop from 250°C to 150°C at constant pressure. What is the final volume if the initial volume is 310 mL?

asked by pari on July 30, 2014
18. ## Physics

A monatomic ideal gas expands from 1.00m^3 to 2.50m^3 st a constant pressure of 2.00x10^5 Pa. Find the change in the internal energy of the gas.

asked by S on November 22, 2012
19. ## thermodynamic

Calculate the work necessary to compress air in an isolated cylinder with initial and final volumes of 6.0 and 1.2 ft^3, respectively. The initial pressure and temperature are 30.0 psia and 50 degree F, respectively.

asked by chris on January 15, 2011
20. ## Chemistry

calculate the volume of oxygen at 15°c and 745mmHg pressure which could be obtain by heating 10g of potassium trioxochloride. (molar volume at stp is 22.4dm3. K = 39, Cl = 35.5 O = 10)

asked by HARISU MIKAILU on January 27, 2019
21. ## Physics

A cyclist and his bicycle have a combined mass of 55kg. Total area of the tyres in contact with the road is 2.2 in contact with pressure exerted by the two on the ground.

asked by Angie on February 15, 2017
22. ## Chemistry

KClO3 decomposes according to the reaction below. How many grams of KClO3 are needed to produce 826ml of O2 at standard temperature and pressure? 2KClO3 → 2KCl + 3O2

asked by Sarah on April 21, 2017
23. ## Chemistry

Benzene has a heat of vaporization of 30.72kJ/mol and a normal boiling point of 80.1 ∘C. At what temperature does benzene boil when the external pressure is 480torr ?

asked by Connor on April 7, 2014
24. ## chem

Of the floowing compound, which would you exoect to have the lowest vapor pressure at room temperature: CHCl3 CH2Cl2 CH3Cl CCl4 From my result I think it is CH2Cl2

asked by Ron on June 11, 2007
25. ## CHEMISTRY

Method for getting correct answer? Thank you! Initially there were equilibrium concentrations of 0.1887 M A, 0.1042 M B. Which of the equations below is correct if the pressure decreased by a factor of 2.40? Use the reaction below. 6A(g) ↔ 5 B(g) a. Qc =

asked by Chemistry on April 6, 2014
26. ## Chemistry

Consider the following chemical equation. Cl2(g) + O2(g) → Cl2O3(g) Assuming all gases are at the same temperature and pressure, how many milliliters of oxygen gas must react to give 3.50 L of Cl2O3?

asked by Kalen on December 5, 2010
27. ## Physics

0.490 mol of argon gas is admitted to an evacuated 50.0 cm^3 container at 60.0 C. The gas then undergoes an isochoric heating to a temperature of 400 C. What is the pressure?

asked by Joe on January 26, 2011
28. ## problem

Benzene has a heat of vaporization of 30.72 kj/mol and a normal boiling point of 80.1. At what temperature does benzene boil when the external pressure is 480 torr?

asked by Anonymous on July 17, 2011
29. ## CHEMISTRY

Method for getting correct answer? Thank you! Initially there were equilibrium concentrations of 0.1887 M A, 0.1042 M B. Which of the equations below is correct if the pressure decreased by a factor of 2.40? Use the reaction below. 6A(g) ↔ 5 B(g) Qc =

asked by Chemistry on April 6, 2014
30. ## chemistry

calculate the concentration of CO2, in a soft drink after the bottle is opened and equilibriates at 25C under a CO2 partial pressure of 0.0003 atm.

asked by Kyle on January 5, 2015
31. ## Physics

A car of four tyres of area 0.06m2 are in contact with the road. Calculate the maximum pressure exerted by each tyre if the car weighs 1200N.

asked by Mercy on October 25, 2018
32. ## chemistry

The melting of 0.140 g of Br2 (which occurs at -7.2 C at 1 atm pressure) absorbs 9.43 J of heat. Compute the enthalpy change in 2.00 mol of Br2 when it freezes.

asked by rafay on September 1, 2011
33. ## chemistry

If a scuba diver's lungs have a normal capacity of 4.9 L at sea level (1.0 atm), what would be the volume of her lungs if the pressure at a depth of 50 ft is 975 mmHg?

asked by Leeya on April 9, 2014
34. ## chemistry

555 mL sample of nitrous oxide at 25 degree celsius is heated to 50 degrees celsius. If the pressure remains constant, what is the final volume?

asked by Anonymous on July 19, 2011
35. ## chemistry

A helium balloon has a volume of 2.50L at STP. If it's released and rised to an elevation at which pressure is 0.285 atm, and the temperature is -35 degrees. What's the new volume?

asked by sarah on January 15, 2012
36. ## chemistry

Which part(s) of the reaction 2O3(g) 3O2(g) will be favored by an increase in the total pressure (resulting in compression)? 2. Neither is favored. 3. Unable to determine 4. reactants

37. ## ahemistry

a sample of waterunder study was found to boil at 102c at normal temperature and pressure.is the water pure?will the water freeze at 0c. comment

asked by anson on September 5, 2011
38. ## Chemistry

N2(g) + O2(g) → N2O5(g) What volume of oxygen gas reacts to yield 750.0 cm3 of N2O5? The reaction conditions are 350°C and 2.50 atm pressure

asked by Harry on February 2, 2014
39. ## Chemistry 103

2NiO(s)→2Ni(s)+O2(g) If O2 is collected over water at 40.0C and a total pressure of 739mmHg , what volume of gas will be collected for the complete reaction of 24.18g of NiO?

asked by YeJi Lee on October 22, 2012
40. ## Physics

A man of mass 75 kg lies on a bed of 10,000 nails. The tip of each nail has an area of 1.0 square millimeter. What pressure does the man experience? [g=10 N/kg]

asked by Erin on April 12, 2014
41. ## Chemistry

Calculate the change in entropy (in J/K) when 61.4 g of nitrogen gas is heated at a constant pressure of 1.50 atm from 25.8 ºC to 92.8 ºC. (The molar specific heats are Cv is 20.8 J/(mol-K) and Cp is 29.1 J/(mol-K) .)

asked by June on March 31, 2015
42. ## physics

Estimate the pressure exerted on the floor by a 75 kg store clerk standing momentarily on a single heel of their shoe, where the heel area = 6 cm square?

asked by ted on November 29, 2011
43. ## Chemistry

An ideal gas confined in a cylinder by a movable piston at 25°C and 150 KPa is heated at constant pressure to 38°C. The Cp of the gas is (7/2)R. Calculate: AH, AU, Q and W in J/mol

asked by Anonymous on September 30, 2018
44. ## physics

When water freezes, it expands about 8.60%. What would be the pressure increase inside your automobile engine block if the water in it froze? The bulk modulus of ice is 2.00 * 10^9 N/m2.

asked by Anonymous on January 31, 2013
45. ## chemistry

what volume of hydrogen sulfide is produced by reaction of 0.5 mole of sodium sulfide with hydrochloric acid at a temp. of 20C and a pressure of 722 mm.

asked by Kimberly on April 12, 2012
46. ## science

(a) What is the name of weather systems centered about regions of low pressure? (b) In what direction do winds in the northern hemisphere spiral around such a region? (c) In the southern hemisphere?

asked by Shirley on October 29, 2011
47. ## Chem

A 500 -cm3 flask contains 0.420g of a gas at a pressure of 160kPa and a temperature of 330K. What is the molecular mass of this gas? M=____g/mol? Ty

48. ## chemistry

a sample of waterunder study was found to boil at 102c at normal temperature and pressure.is the water pure?will the water freeze at 0c. comment

asked by anson on September 5, 2011
49. ## Physics...NEED HELP

Physics help. what are the steps to solving the following problems? Attack on the ice fortress! A comic book villain has taken shelter in an ice fortress in an attempt to hide from the Avengers. Apparently, though, only the Hulk and some guy with a cannon

asked by Greg on May 3, 2013
50. ## Math

In the last basketball game, Kevin scored 2 less than a third of his team's points. Part A: Let n represent the number of points Kevin's team scored. Write an expression for the number of points Kevin scored. Part B: Kevin scored 14 points. How many points

asked by Manny on February 10, 2017
51. ## algebra

17. In the last basketball game, Kevin scored 2 less than a third of his team's points. Part A: Let n represent the number of points Kevin's team scored. Write an expression for the number of points Kevin scored. Part B: Kevin scored 14 points. How many

asked by Anonymous on April 14, 2016
52. ## mechanics

Find the total kinetic energy of a 1500 g wheel, 700 mm in diameter, rolling across a level surface at 650 rpm. Assume that the wheel can be considered as a hoop. (b) For the wheel in part (a), calculate the torque required to decrease its rotational speed

asked by george on May 14, 2013
53. ## Chemistry- gaz and stoechiometry

The preparation of KClO3 follows these equations: 2KMnO4 + 16HCl->2KCl + 2MnCl2 + 5Cl2 (g) + 8H2O 3Cl2 (g) + 6KOH ->KClO3 + 5KCl + 3H2O 1) How many moles of KClO3 are produced by one mole of KMnO4 I think the only link between the two equations is Cl2 but

asked by Ele on April 28, 2016
54. ## chemistry

You took 0.99ml of a hexokinase assay solution and added 10 ul of an unknown glucose sample. The absorbance at 340nm is 0.422 the extinction coefficient is 6.22x10^3 the molecular mass of glucose is 180.16g/mol. What is the concentration of glucose in the

asked by lacy on September 30, 2013
55. ## chemistry

You took 0.99ml of a hexokinase assay solution and added 10 ul of an unknown glucose sample. The absorbance at 340nm is 0.422 the extinction coefficient is 6.22x10^3 the molecular mass of glucose is 180.16g/mol. What is the concentration of glucose in the

asked by lacy on September 30, 2013
56. ## Chemistry

Helium-oxygen mixtures are used by divers to avoid the bends and are used in medicine to treat some respiratory ailments. What percent (by moles) of Helium is present in a helium-oxygen mixture having a density of 0.538 g/L at 25 degrees C and 721 mmHg?

asked by Ellen on October 10, 2010
57. ## Chemistry

Please check my answers. 1. Using the equations, IO3- +5I- + 6H+ -> 3I2 + 3H2O C6H8O6 + I2 -> C6H6O6 + 2I- + 2H+ how many equivalents of IO3- are required to produce enough I2 to oxidize one equivalent of ascorbic acid? Answer: 1IO3- 3I2 3C6H8O6 1/3

asked by Sara on February 27, 2011
58. ## Math

Blair is decorating a birthday cake with candles. The cake has a diameter of 15 inches. She wants to place the candles about every 6 inches around the edge. How many candles will she need? How could i solve this problem?

asked by Nina on September 8, 2015
59. ## MATH WORD PROBLEM HELP PLEASE

A water tank is in the shape of a right circular cylinder with a height of 20 feet and a volume of 320pi cubic feet. What is the diameter, in feet, of the water tank?

asked by Anonymous on April 14, 2015
60. ## math

An open cylindrical tank has an internal diameter of 5.6 cm and an internal height of 4 cm. The inside of the tank was painted. What area of the tank in square centimeter, was painted?

asked by kudu on March 17, 2015
61. ## Physics

Two 2.9-cm-diameter electrodes with a 0.15-mm-thick sheet of Teflon between them are attached to a 9.0 V battery. Without disconnecting the battery, the Teflon is removed. a) What are the electric field after the Teflon is removed?

asked by Leanna on October 6, 2013
62. ## Geometry

Dana is planning to ride her bicycle around the circular race track and wants to know the distance. If the diameter of the track is 2 mile, how far is the distance around the race track? 3.14(2) = 6.28 miles

asked by Sue on March 8, 2016
63. ## Physics

At what speed does water escape from a large open-top tank through an opening 2.00 cm in diameter. The opening is 3.00 m below the water level of the tank on the side of the tank.

asked by Anonymous on May 30, 2016
64. ## algebra

A three quarter inch wire has 12 ohms resistance. How much resistance has the same length of half-inch wire, if resistance varies inversely as the square of the diameter?

asked by Don on May 23, 2014
65. ## physics

A constriction in a pipe reduces its diameter from 7.9 cm to 1.8 cm . Where the pipe is wider, the fluid velocity is 8 m/s. Find the fluid velocity where the pipe is narrow. Answer in units of m/s

asked by andre on November 6, 2014
66. ## algebra function

Area of a window. A window is in the shape of a square of side s, with a semicircle of diameter s above it. Write a function that expresses the total area of the window as a function of s.

asked by Lizzy on October 6, 2007
67. ## Math

The diameter of a car's tire is 60cm . While the car is being driven , the tire picks up a nail .How high above the ground is the nail after the car has travelled 1km

asked by Melissa on December 8, 2011
68. ## math

a water tank measures 12o feet in diameter and is 50 feet high .how many cubic feet of water can it hold ,to the nearest cubic foot ?

asked by asma on January 29, 2010
69. ## chemistry

Suppose a student diluted and titrated a bleach unknown. A single titration was performed which required 14.42 mL of 0.100 M Na2S2O3. The density of the original, undiluted bleach unknown was 1.042 g/mL. calculate the number of moles of ClO- in the sample

asked by Morgan on October 27, 2013
70. ## Chemistry

A solution containing 7.00grm of lead nitrate is combined with a solution containing 7.00g of sodium sulfate. (a) write a balance equation for the reaction. Pb(no3)2 aq + NaSo4 aq ---> PbSo4 +2 NaNo3. I think that's right. (b)How many moles of the the

asked by Mike on March 9, 2010
71. ## Analytical Chemistry

What volume, in liters, of 1.09 M KOH solution should be added to a 0.102 L solution containing 9.35 g of glutamic acid hydrochloride (Glu, FW = 183.59 g/mol; pKa1 = 2.23, pKa2 = 4.42, pKa3 = 9.95) to get to pH 10.26? Should I start with molar

asked by R on July 5, 2016
72. ## general chem

Calculate the molarity of a solution made by dissolving 12.5 grams of Na2CrO4 in enough water to form exactly 550 mL of solution. (b) How many moles of KBr are present in 150 mL of a 0.275 M solution? (c) How many milliters of 6.1 M HCl solution are needed

asked by rob on October 9, 2011
73. ## Chemistry

I need to calculate the amount of NaH2PO4 (in grams) and 1.00M NaOH solution (in ml) needed to make 250 ml of 0.20M H2PO4- at pH 8.00. My work is lengthy and involved but the answer I got was 7.00 ml of the NaOH and 0.0070 moles of the NaH2PO4 needed. Can

asked by Kelsy on May 12, 2015
74. ## Chemistry

I need to calculate the amount of NaH2PO4 (in grams) and 1.00M NaOH solution (in ml) needed to make 250 ml of 0.20M H2PO4- at pH 8.00. My work is lengthy and involved but the answer I got was 7.00 ml of the NaOH and 0.0070 moles of the NaH2PO4 needed. Can

asked by Kelsy on May 12, 2015
75. ## Physics

A movable piston having a mass of 7.26 kg and a cross-sectional area of 5.26 cm2 traps 0.250 moles of an ideal gas in a vertical cylinder. If the piston slides without friction in the cylinder, how much work will the gas do when its temperature is

asked by Lauren on April 28, 2011
76. ## general chem

Calculate the molarity of a solution made by dissolving 12.5 grams of Na2CrO4 in enough water to form exactly 550 mL of solution. (b) How many moles of KBr are present in 150 mL of a 0.275 M solution? (c) How many milliters of 6.1 M HCl solution are needed

asked by rob on October 9, 2011
77. ## ACCT

The question is: In the journal provided, prepare year- end adjustments for the following situations. Omit explanations. a. accrued interest on notes receivable is \$105 b. of the \$12,000 received in advance of earning a service, one third was still

asked by Tan on March 1, 2012
78. ## Math

A bicycle wheel is 30 inches in diameter. a. to the nearest revolution, how many times will the wheel turn if the bicycle is ridden for 3 miles. b. suppose the wheel turns at a constant rate of 2.75 revolutions per second. What is the linear speed in miles

asked by Thomas on November 19, 2007
79. ## calculus

Gravel is being dumped from a conveyor belt at a rate of 10 cubic feet per minute. It forms a pile in the shape of a right circular cone whose base diameter and height are always equal to each other. How fast is the height of the pile increasing when the

asked by Ash on October 29, 2009
80. ## Physics - Fluids

A cylindrical diving bell 3.0 m in diameter and 4 m tall with an open top of 25 degrees celsius, and the air temp 220 down is 5 degrees celsius. The density of seawater is 1025 kg/m^3. How high does the sea water rise in the bell when the bell is

asked by Peter on December 17, 2008
81. ## magnetism

Many metals become superconductors (zero resistance, zero loss, zero heating) at low temperatures. If they are warmed above the critical tempareature, the superconductivity is lost. Also, if the metal experiences a magnetic field above a critical value,

asked by Sue on December 2, 2013
82. ## Physics

A bicyclist starts from rest and accelerates at a constant rate for 15.0s. After 10.0s the bicycles front wheel is turning at a rate of 2.5 rev/s. The tire wheel has a diameter of 0.8m. A)Through how many revolutions does the wheel turn in the first 10.0s?

asked by courtney on June 18, 2012

Gravel is being dumped from a conveyor belt at a rate of 20 cubic feet per minute. It forms a pile in the shape of a right circular cone whose base diameter and height are always equal to each other. How fast is the height of the pile increasing when the

asked by Roy on March 15, 2009
84. ## physics

As part of a class project you are given 0.900 g of nichrome and asked to fabricate a wire with uniform cross-section. You use up 95% of the nichrome and make a wire with a resistance of 0.840 Ω. The resistivity of nichrome is 1.00 10-6 Ω · m and its

asked by Justin on September 15, 2013
85. ## calculus

Gravel is being dumped from a conveyor belt at a rate of 30 cubic feet per minute. It forms a pile in the shape of a right circular cone whose base diameter and height are always equal to each other. How fast is the height of the pile increasing when the

asked by jon on October 18, 2010
86. ## calculus

Gravel is being dumped from a conveyor belt at a rate of 30 cubic feet per minute. It forms a pile in the shape of a right circular cone whose base diameter and height are always equal to each other. How fast is the height of the pile increasing when the

asked by jon on October 18, 2010
87. ## math (trigonometry)

A ferris wheel has a diameter of 100m and the bottom of the wheel is 4m above the ground. It rotates two times every 10 minutes. Using this information, complete each question. c) Determine the angular velocity of the Ferris wheel in radians/second d)How

asked by Laura on January 27, 2018
88. ## Chem

Okay so I have this assignment and I thought I knew how to do this but appearntly I am just lost. I know what the answer is suposed to be and I am deifantly no wheres near that. If you can sorta point me in the right direction that would be great. Thanks!

asked by Tracy on September 24, 2006
89. ## Chemistry

I have a 1L solution of 0.02M sodium acetate and 0.02M acetic acid. What is the pH after the addition of 0.05 moles of hydrochloric acid? I know this is a buffer question but I have no idea how I am supposed to go about getting the answer... I know Ka

asked by Alex on March 4, 2010
90. ## Intro to chem

What is the volume of 19.7g of oxygen at STP? Heres what i got but did not get the same answer..pls tell me where i am wrong! (grams to moles) 19.7g x 1 mol/ 16.00 = 1.23 mol Oxygen (Pv=nRT) looking for V 1.23 mol x 0.0821 x 273K / 1.00 atm = 27.57 CORRECT

asked by pooja on April 14, 2011
91. ## Math

The pH of a solution ranges from 0 to 14. An acid has a pH less than 7. Pure water is neutral and has a pH of 7. The pH of a solution is given by pH = -logx where x represents the concentration of the hydrogen ions in the solution in moles per liter. Find

asked by lili on January 6, 2017
92. ## Science

It is found that 24.68 mL of 0.1165 NaOH is needed to titrate 0.2931 g of an unknown acid to the phenolphthalein end point. What is the equivalent mass of the acid? equivalent mass = grams acid/moles H+

asked by Mini on February 5, 2009
93. ## Chemistry 30

A mixture of 2.5 moles of H2O and 100 g of C are placed in a 50.0 L container and allowed to come to equilibrium in the following reaction: C(s) + H2O(g)  CO(g) + H2(g) The equilibrium concentration of hydrogen gas is found to be 0.040 M. What is the

94. ## Physical sciences

Copper reacts with silver nitrate according to the equation: Cu(s) + 2AgNO3(aq)= Cu(NO3)2(ag) +2Ag(s). If 0.50mol of copper is added to 1.5mol of silver nitrate , which is the limiting reagent and how many moles of silver are formed

asked by Tersia Malatji on June 17, 2013
95. ## Chem

A mixture of 2.5 moles of H2O and 100 g of C are placed in a 50.0 L container and allowed to come to equilibrium in the following reaction: C(s) + H2O(g)  CO(g) + H2(g) The equilibrium concentration of hydrogen gas is found to be 0.040 M. What is the

96. ## Chemistry

What is the molarity of a 5.00 x 102 ml solution containing 2490 g of KI? How many moles of LiF would be required to produce a 2.5 M solution with a volume of 10.5 L? How many grams of NaI would be used to produce a 2.0 M solution with a volume of 10.00 L?

asked by Clea on March 24, 2014
97. ## Chemistry

How many atoms of mercury are present in 5.4 cubic cm of liquid mercury? The density of mercury is 13.55g/cc. mass Hg = volume x density Then convert to moles. Then remember there are 6.022E23 atoms for every mole. I still don't get how to do this! HELP

asked by Jessica on October 27, 2010
98. ## Chemistry

Sulfur and fluorine react in a combination reaction to produce sulfur hexafluoride: S (s) + 3F2 (g) SF6 (g) What is the minimun number of moles of fluorine gas needed to completely react with 16 g sulfur? a. 1 b. 1.5 c. 2 d. 3 e. 6

asked by Courtne on November 1, 2009
99. ## Chemistry

How many moles of conjugate base (Na2HPO4) are present in 40mL of .010M buffer at pH 7.5 vs at pH 6? Buffer was made up of Na2HPO4 and NaH2PO4. pH=pKa +log[A/HA]; pKa=7.2.... When I did the calculations I got the same amount as if it were in a 0.1M buffer

asked by Heidi on September 16, 2017
100. ## Math

The pH of a solution ranges from 0 to 14. An acid has a pH less than 7. Pure water is neutral and has a pH of 7. The pH of a solution is given by pH = -logx where x represents the concentration of the hydrogen ions in the solution in moles per liter. Find

asked by Liz on May 23, 2016