Wednesday

October 22, 2014

October 22, 2014

Number of results: 52,974

**chem HELP PLEASE its physics side of chem **

given E, = l^2 h^2 / 2 m r^2 calculate energies for an electron localised to a circle of radius 2 x 10^-9 m for l = 0,1,2, draw pictures of three levels and calculate the relative populations of these levels at 300K i did the first bit but came out with, 0, 6.0249 x 10-6 J mol...
*October 27, 2009 by poppy*

**chemistry**

Calculate the number of grams of reactant left over when 28.35 grams of silver reacts with 50.0 liters of air at STP which is 20.9476 % oxygen by volume. The density of air at STP is 1.292 g/L. attemtp at solution volume of oxygen= .209476*50L=10.5L How do i go from volume of ...
*November 8, 2008 by jason*

**Chemistry - please this is urgent**

To a calorimeter containing 41.80g of water at 29.95oC, 11.7999 of a salt was added with stirring. As the salt dissolved, the temperature rapidly changed to 37.85oC before slowly returning to room temperature. 1. Calculate the Heat of Solution. Given that the Heat of Formation...
*March 14, 2008 by girl who needs help in chemistry right now*

**geometry**

The rectangle ABCD is rotated about the side AB. Find the volume of the solid defined by this rotation. AB = DC = 4cm AD = CB = 2cm
*January 9, 2011 by peter*

**density**

Suppose two worlds, each having mass M and radius R, coalesce into a single world. Due to gravitational contraction, the combined world has a radius of only 3/4R. What is the average density of the combined world as a multiple of p0, the average density of the original two ...
*December 1, 2013 by Rebecca*

**chemistry**

ohh im sorry i also have another problem i don't understand. "A rectangular solid measures 1.0 m by 5.6 cm by 2.1 dm. Express its volume in cubic meters, liters, cubic inches, and cubic feet." i don't even know what dm means ! Someoneee please help me!
*July 21, 2008 by Jecce*

**chemistry**

A 4.14 m solution of the solute methylene chloride dissolved in the solvent ethanol is available. Calculate the mass ( kg ) of the solution that must be taken to obtain 1487 g of methylene chloride density: CH2Cl2-1327(kg/m^3) C2H5OH-789.3(kg/m^3)
*January 28, 2010 by bubble*

**Chemistry Science**

calculate the mass of carbon dioxide that would be produced when one gas of tank of gasoline (use octane) is burned in the air. assume an 80 liter gas tank and 0.703 g/ml as the density of octane
*August 30, 2014 by Joan*

**AP Chemistry, Chem, science**

Can anyone please help me with this problem?? =/ The reaction between solid sodium and iron (III) oxide is one in a series of reactions that inflates an automobile airbag. If 100g of sodium and 100g of iron(III) oxide are used in this reaction, determine: a. the balanced ...
*September 14, 2012 by Layla*

**Physics (please help!!!!)**

A man of mass 80 kg and density 970 kg/m3 stands in a shallow pool with 31% of the volume of his body below water. Calculate the normal force the bottom of the pool exerts on his feet. (Take the positive direction to be up. Indicate the direction with the sign of your answer.)
*April 16, 2011 by HELP!!!!*

**Physics - Oscillations**

An astronaut measures her mass by means of a device consisting of a chair attached to a large spring. The period of oscillation she undergoes when set into motion is used to determine her mass. If her mass, together with the chair, is 172kg, and the time required for her to ...
*November 18, 2013 by Mikhail*

**chemistry**

More dilute sodium hydroxide solutions are often prepared from a sastuated sodium hydroxide soltuion thats is 52.0% by mass and has a density of 1.48 g/mL. Calculate the volume, in liters, of this solution needed to prepare 35.0 L if 0.125 M sodium hydroxide?
*March 30, 2011 by conlan*

**Physics - KE/Inertia**

The rigid body shown in Figure 10-66 (it is a triangle with the upper mass = to M and the bottom two corners/masses equal to 2M. The bottom side length equals .70 cm with point P in the middle of the side and the other two sides equal .55 cm)consists of three particles ...
*March 26, 2007 by COFFEE*

**physicss**

A cube with sides each 3cm long has 8 charges of Q = 25nC at each corner. What is the electric potential \Delta V at the center of the cube with respect to infinity, which is defined to have V=0 V?
*October 17, 2012 by Anthony*

**math**

a storage crate has the dimensions : 12ft * 6ft *5ft. how many cube-shaped boxes measuring 8 inches in length could be stacked completely within the cube??
*April 10, 2013 by tina*

**math**

a storage crate has the dimensions : 12ft * 6ft *5ft. how many cube-shaped boxes measuring 8 inches in length could be stacked completely within the cube??
*April 10, 2013 by kyle*

**math**

a storage crate has the dimensions : 12ft * 6ft *5ft. how many cube-shaped boxes measuring 8 inches in length could be stacked completely within the cube??
*April 10, 2013 by julia *

**10th grade**

The ratio of the measures of three sides of a triangle are 1/2:1/3:1/5, and its perimeter is 6.2 centimeters. find the measure of each side of the triangle
*January 22, 2009 by Edisooner*

**math**

One of the angles of a right triangle measures 30°, and the hypotenuse is 10 inches long. How long is the side opposite the 30° angle?
*September 5, 2010 by ben*

**physics**

A person weights 685 N in air but only 497 N when standing in water up to the hips. Find (a) the volume of each of the person’s legs and (b) the mass of each leg, assuming they have a density that is 1.05 times the density of water.
*March 25, 2013 by Jess*

**chemistry**

a solid substance has a density of 4.36 g/ml. what is the volume of 30 g of this substance?
*December 12, 2011 by jessica lou*

**Math help please**

calculate missing dimension. square based pyramid has height 92cm and volume 5.4 m cube.
*September 30, 2010 by Annie*

**Geometry/Math**

Calculate the volume to the nearest tenth of a 6.3-m cube with a hole 2 m in diameter drilled through it. Use 3.14 for pi.
*May 21, 2012 by Lex*

**Finding the Molecular Formula**

A certain compound containing only carbon and hydrogen was found to have a vapor density of 2.550 g/L at 100 degrees C and 760 mm Hg. If the empirical formula of this compound is CH, what is the molecular formula of this compound? I had some ideas as to how to solve this ...
*December 8, 2012 by Amy*

**chemistry**

Calculate the energy that must be removed to convert substance X from a gas at 115°C to a solid -50.7°C. Assume X has a molar mass of 75.0 g/mol. Specific heat capacities ΔHvap 20. kJ/mol C(s) 3.0 J/g · °C ΔHfus 5.0 kJ/mol C(l) 2.5 J/g · °C bp 75°C C(g) 1.0 J/g · °C ...
*April 19, 2010 by Trish*

**chemistry**

Calculate the energy that must be removed to convert substance X from a gas at 115°C to a solid -50.7°C. Assume X has a molar mass of 75.0 g/mol. Specific heat capacities ΔHvap 20. kJ/mol C(s) 3.0 J/g · °C ΔHfus 5.0 kJ/mol C(l) 2.5 J/g · °C bp 75°C C(g) 1.0 J/g · °C ...
*April 19, 2010 by Trish*

**science**

If the volume of 26.100 grams of chloroform has a density of 1.49 g per ml, then what is the mass? I got 18.125. Is this correct? My other question is, if the mass of an aspirin is 250 mg, then what is the mass in kg? I got, .00025. Is this correct? Thanks, Elise
*February 19, 2009 by Elise*

**Science**

If the volume of 26.100 grams of chloroform has a density of 1.49 g per ml, then what is the mass? I got 18.125. Is this correct? My other question is, if the mass of an aspirin is 250 mg, then what is the mass in kg? I got, .00025. Is this correct? Thanks, Elise
*February 19, 2009 by Elise*

**Chemistry**

A piece of dry ice (solid carbon dioxide) with a mass of 25.5 g is allowed to sublime (convert from solid to gas) into a large balloon. Assuming that all of the carbon dioxide ends up in the balloon, what will be the volume of the balloon at a temperature of 18 degrees Celsius...
*February 24, 2011 by Jake*

**Chemistry**

A piece of dry ice (solid carbon dioxide) with a mass of 25.5 g is allowed to sublime (convert from solid to gas) into a large balloon. Assuming that all of the carbon dioxide ends up in the balloon, what will be the volume of the balloon at a temperature of 18 degrees Celsius...
*February 24, 2011 by Jake*

**Math **

Determine the number of triangles that could be drawn with the given measure. Then, find the measures of the other angles and the other side in each possible triangle. Round side lengths to the nearest tenth of a unit and angle measure to the nearest tenth of a degree, where ...
*June 10, 2014 by Han*

**geometry**

An isosceles triangle has a base of 9.8 units long. If the congruent side lengths have measures to the first decimal place, what is the shortest possible length of the sides.
*October 23, 2011 by Billy*

**math**

An isosceles triangle has a base 9.6 units long. If the congruent side lengths have measures to the first decimal place, what is the shortest possible length of the sides?
*July 1, 2014 by sara*

**science**

Erin must perform a science experiment. She needs to dissolve 10 g of salt in 250 ml of water. She measures the water incorrectly and dissolves the 10 g of salt in 350 ml of water. Now she has no more salt. Explain what Erin can do to make the solution accurate.
*April 29, 2008 by astrid*

**chemistry**

A 4.58 m solution of the solute methylene chloride dissolved in the solvent acetone is available. Calculate the mass ( kg ) of the solution that must be taken to obtain 0.8848 kg of methylene chloride. density: CH2Cl2-1.327 (g/mL) (CH3)2CO-0.7899 (g/mL)
*January 28, 2010 by bubble*

**Chemistry**

Balance Eq.: Na2Co3+ CaCl2--> CaCo3+ 2NaCl. (CHALK) Calculate the mass of a dry precipitate. Calculate the mass of moles of the precipitate produced in the reaction.
*October 28, 2007 by Monte;*

**Physics please check**

The "karat" is a dimensionless unit that is used to indicate the proportion of gold in a gold-containing alloy. An alloy that is one karat gold contains a weight of pure gold that is one part in twenty-four. What is the volume of gold in a 20.0 karat gold necklace whose weight...
*April 9, 2007 by Mary*

**chemistry**

You are analyzing a solid isolated from a reaction and find that its boiling point is over 1000 ∘C. You dissolve the compound in water solution and recrystallize it to produce some solid crystals that you use to determine that the compound is a crystalline solid. Which ...
*January 23, 2014 by Sheila*

**Math/Algabra**

The perimeter of a triangle is 102. side b is twice as long as side A. and side C is three less than side B.. how long is each side.
*February 13, 2011 by Randy*

**Chemistry**

Can someone please help me out here? I've tried several times and i keep getting the wrong answer :( lol A small crucible is filled with 100.00 mL of n-hexadecane (MW (226.44 g/mol), density (0.7703 g/mL)) and 2.10 L of 7-octenyltrichlorosilane (MW (245.65 g/mol), density (1....
*January 21, 2013 by Tawnya*

**physics**

A record player is spinning at 32 rpm when the motor is switched off. After 6.8 seconds the angular speed has decreased to 20 rpm. Calculate the frictional torque if the record player can be treated as a solid wheel of mass 2.4 kg and radius 15 cm. A) 476.47059 Nm B) 0.00499 ...
*November 28, 2010 by emily *

**High school chem 1**

4NH3(g) + 5O2(g) -> 4NO(g) + 6H20(g) what mass of H2O can be produced from 350 liters of NH3?
*March 1, 2011 by tyler*

**physics**

A flask has a mass of 78.23 g when empty and 593.63 g when filled with water. When the same flask is filled with concentrated sulfuric acid, H2SO4, its mass is 1026.57 g. What is the density of concentrated sulfuric acid? (Assume water has a density of 1.00 g/cm3 at the ...
*September 6, 2010 by Jack*

**chemistry**

A flask has a mass of 78.23 g when empty and 593.63 g when filled with water. When the same flask is filled with concentrated sulfuric acid, H2SO4, its mass is 1026.57 g. What is the density of concentrated sulfuric acid? (Assume water has a density of 1.00 g/cm3 at the ...
*September 6, 2010 by Jack*

**Physics Help..**

A small cube (m=0.290 kg) is at a height of 261 cm up a frictionless track which has a loop of radius, R = 28.71 cm at the bottom. The cube starts from rest and slides freely down the ramp and around the loop. Find the speed of the block when it is at the top of the loop. A ...
*February 12, 2014 by Ron*

**Geometry**

A study draws triangle with a perimeter 36cm.the study says that the longest side measures 18cm. how do you know that the student is incorrect?
*January 31, 2011 by JUn*

**wchs**

A checkerboard measures 144 square inches. What is the length of a small square on its side? Hint: It has 8 squares per edge.
*January 30, 2012 by Clara*

**Geometry/Math again!**

The base of a prism is a regular hexagon that measures 4 cm on each side. The prism has a height of 13 cm. What is its total surface area?
*May 21, 2012 by Lex*

**TO MS SUE SCIENCE HELP**

These are my last 2 questions i need help on.... 1. to determine the density of an irregularly shaped object, a student immersed the object in 21.2 ml of water in a graduated cylinder, causing the level of the water to rise to 27.8 ml. If the object had a mass of 22.4 g, what ...
*December 14, 2012 by SPIKE*

**Chemistry**

A 893 g sample of a solution of the solute (CH3)2CO in the solvent C4H8O that has a concentration of 28.6 pph by mass (CH3)2CO is available. Calculate the amount (g) of acetone that is present in the sample. Molar Mass (g/mol) (CH3)2CO 58.05 C4H8O 72.12 Density (kg/m3): (CH3)...
*February 14, 2010 by Anonymous*

**Chemistry**

What is true for water? A) In a phase diagram the solid-liquid coexistance line has a negative slope. B) In a phase diagram the solid-liquid coexistance line has a positive slope. C) The solid is more dense than the liquid. D) The solid is less dense than the liquid. E) The ...
*December 9, 2012 by Anon*

**Chemistry**

If 0.790 mol of solid TiO2 and 8.53 g of solid C are reacted stoichiometrically according to the balanced equation, how many moles of solid TiO2 remain? 3TiO2(s) + 4C(s) + 6Cl2(g) → 3TiCl4(l) + 2CO2(g) + 2CO(g)
*February 10, 2009 by Anonymous*

**science**

a u-tube is partially filled with water.oil which does not mix with water is next poured into one side until water rises by 2.5cm on the other side.if the density of oil be 0.8 ,the oil level will stand higher than the water level by how much?
*May 17, 2012 by abuobaida johar*

**chemistry **

please check if I did this right ... calculate the mass of white solid CaCO3 that forms when 98ml of a 0.1M Ca(NO3)2 solution is mixed with 54 ml of a 2.5M Na2CO3 solution. Ca(NO3)2 + 2NaCO3 -> Ca(CO3)2 + 2NaNO3 .098*0.1 =.0090 .054*2.5 =.135 limiting reactant is Ca(NO3)2 ....
*January 29, 2010 by Krissy*

**Chem I**

Calculate the concentrations of hydronium and hydroxide ions in a solution prepared by dissolving 0.345g of solid NaOH in enough water to make 225mL of solution. Also calculate the pH and pOH of the solution.
*November 15, 2010 by Natalea*

**Science**

One edge of a copper cube is carefully measured and found to be 2.162 cm. An atom of copper is a sphere 0.2560 nanometers in diameter. Assuming that the volume of the cube contains nothing but copper atoms, how many copper atoms are contained in the cube? (the volume of a cube...
*September 24, 2011 by Laurel*

**Physics**

Why do your vowels examples ("aaah", "eee", "uhh") sound different then when I make them? Explain. Tension, mass density and the length of our vocal cords differ so would that be the reason why they sound different? For instance: a child's voice is usually higher pitched than ...
*March 1, 2008 by Andrea*

**math**

If a cube is built from an one inch cubes and if each new cube has an edge N times as long as the previous model what would be true of consecutive surface areas
*March 31, 2011 by Cheyenne*

**physics**

Each of the following objects has a radius of 0.180 m and a mass of 2.65 kg, and each rotates about an axis through its center (as in the table below) with an angular speed of 41.4 rad/s. Find the magnitude of the angular momentum of each object. a) a hoop ___ kg m/s b) a ...
*December 15, 2012 by anonymous*

**physics**

Each of the following objects has a radius of 0.180 m and a mass of 2.65 kg, and each rotates about an axis through its center (as in the table below) with an angular speed of 41.4 rad/s. Find the magnitude of the angular momentum of each object. a) a hoop ___ kg m/s b) a ...
*December 15, 2012 by anonymous*

**math**

A building lot in a city is shaped as a 30° -60° -90° triangle. The side opposite the 30° angle measures 41 feet. a. Find the length of the side of the lot opposite the 60° angle. b.Find the length of the hypotenuse of the triangular lot. c. Find the sine, cosine, and tangent ...
*March 8, 2013 by allison*

**prealgebra**

A building lot in a city is shaped as a 30° -60° -90° triangle. The side opposite the 30° angle measures 41 feet. a. Find the length of the side of the lot opposite the 60° angle. b.Find the length of the hypotenuse of the triangular lot. c. Find the sine, cosine, and tangent ...
*July 31, 2014 by Anonymous*

**maths**

A paving block is is in the shape of a prism, the area of it' cross section being 154cm^2.The prism i 17cm long ad the material from whih it is made has a density of 2.2g/cm^3. Calculate the mass of the paving block. Please can you tell me the method aswell thanks
*June 6, 2009 by chelsea*

**math**

The volume of cube I is 331 m^3 less than the volume of cube II. If an edge of cube I is 10 meters, an edge of cube II is A. 14 meters B. 13 meters C. 12 meters D. 11 meters
*August 15, 2014 by Troy*

**Chemistry**

In a laboratory activity, a student team measures the heat released by burning heptane. Using the following data, calculate the molar heat of combustion of heptane in kJ/mol: Mass of water - 179.2 g Initial water temperature - 11.6 degrees C Final water temperature - 46.1 ...
*April 21, 2008 by Natasha*

**physics**

To determine the density of block of aluminum, you measured the mass at 101.1 g and a volume of 38.2 cm3 . When you looked up the value for aluminum density you found out it should be 2700 kg/m3 What is the percent error for your experimental data? a) 1.98% c) 19.8% b) 0.198...
*January 20, 2011 by Anonymous*

**chemistry **

A 893 g sample of a solution of the solute (CH3)2CO in the solvent C4H8O that has a concentration of 28.6 pph(parts per hundred) by mass (CH3)2CO is available. Calculate the amount (g) of acetone that is present in the sample. Molar Mass (g/mol) (CH3)2CO 58.05 C4H8O 72.12 ...
*February 16, 2010 by Angel *

**chemistry**

Determine the mass of NaCl in 1.0 L of 3.0 % by mass aqueous solution of sodium chloride. The density of the solutions is 1.10 gmL-1 please explain all the steps, thanks!
*December 8, 2010 by Stacy*

**Pre-Algebra**

Q: A building lot in a city is shaped as a 30° -60° -90° triangle. The side opposite the 30° angle measures 41 feet. a. Find the length of the side of the lot opposite the 60° angle. b. Find the length of the hypotenuse of the triangular lot. C.Find the sine, cosine, and ...
*June 22, 2014 by DArko*

**Chemistry**

A newly discovered giant planet has an aver- age radius 12 times that of the Earth and a mass 722 times that of the Earth. Calculate the ratio of the new planet’s den- sity to the Earth’s density.
*September 14, 2010 by Daniel*

**physics**

The density of ice is 917 kg/m3, and the density of sea water is 1025 kg/m3. As shown is the figure, a polar bear climbs onto a piece of ice, which has a volume of 5.75 m3, and is floating in sea water. a) What is the mass of the piece of ice? b) What is the mass of the ...
*March 9, 2013 by Chris*

**science**

An object measures 12 x 3 x 2.5 cm and has a density of 0.6 g/cm3. When it is placed in water, what is the volume of the part of the object that is above the surface of the water?
*September 19, 2011 by frankie*

**science**

An object measures 12 x 3 x 2.5 cm and has a density of 0.6 g/cm3. When it is placed in water, what is the volume of the part of the object that is above the surface of the water?
*September 25, 2011 by Anonymous*

**science**

An object measures 12 x 3 x 2.5 cm and has a density of 0.6 g/cm3. When it is placed in water, what is the volume of the part of the object that is above the surface of the water?
*September 25, 2011 by Anonymous*

**chemistry**

At 25 degrees celsius, the dimensions of a rectangular block of gold are 4.42 cm by 3.07 cm by 2.63 cm. The mass of the gold is 689g. I found that the density is 19.3g/cm^3 at 25 degrees but how will the density change if the temperature is increased to 125 degrees?
*September 30, 2010 by kate*

**physics torque and shelf**

When a wood shelf of mass 6.1 kg is fastened inside a slot in a vertical support, the support exerts a torque on the shelf. The board is 32cm wide by 3cm tall. the slot is 2 cm wide (3cm tall)on the lefthand side. So there are three vertical forces. A) Calculate the upward ...
*May 22, 2009 by kelsi*

**Chemistry**

Instant cold packs used to treat athletic injuries contain solid NH4NO3 and a pouch of water. When the pack is squeezed, the pouch breaks and the solid dissolves, lowering the temperature because of the following endothermic reaction. NH4NO3(s) + H2O(l) = NH4NO3(aq) ÄH = +25.7...
*February 1, 2011 by Don*

**Physics**

A 65kg person's density is 990kg/m^3 with 2.4 L of air in lungs. What vol of air would the person have to expel to bring the density to that of water 1000 kg/m^3 (neglect the mass of air)?
*November 13, 2011 by Mily*

**MATH**

1;The lengths of two sides of atrisngle are 12cm and 15cm.between what two measures should the length of the third side fall.
*August 17, 2012 by AMIT KUMAR*

**Chemistry**

If the column of water in the water barometer fore to a height of 35ft, what would the atmospheric pressure be in mm Hg? mmH20X(density of water/density of Hg)= mmHg Density of water=0.99707 Density Hg=13.5340
*February 11, 2011 by Brian*

**Math 7**

Suppose you copy a drawing of a polygon with the given size factor. How will the side lengths, angle measures, and perimeter of the image compare to those of the original? A.) 200% B.) 150% C.) 50% D.) 75%
*January 15, 2013 by Brandon*

**Physics**

A cubical block of wood 0.100 m on a side and with a density 550 kg/m^3 of floats in a jar of water. Oil with a density of 750 kg/m^3 is poured on the water until the top of the oil layer is 0.035 m below the top of the block. 1. How deep is the oil layer? Please tell me the ...
*January 17, 2014 by Lisa*

**Chemistry**

A photon has a wavelength of 350 nm. Calculate the energy of the photon in joules
*November 6, 2010 by kevin*

**Calculus**

If the tolerance on the volume of a cube is a 2% error then what should the tolerance be fore each side? So what i did was V=x^3 dV = 3x^2 dx dV/V = 2% What should I do next? the answer is 2/3% but I don't know how it works. Thanks.
*November 3, 2008 by Andrew*

**maths**

When two cube of side 12 cm are joined end to end to form a cuboid then the total surface area of cuboid is
*November 30, 2012 by maihul*

**Chemistry **

Calcium can also be precipitated out of the solution by adding sodium phosphate (Na3PO4) to form solid calcium phosphate. A.) write a net ionic equation for this process B.)calculate the mass of this precipitate you would generate from treating 1.000 L of your unknown sample ...
*March 25, 2014 by Mai*

**chemistry**

Common ion effect;At some other temperature, a solid sample of Ca(OH)2 is shaken with 0.0100? Common ion effect;At some other temperature, a solid sample of Ca(OH)2 is shaken with 0.0100 M CaCl2. Once equ? At some other temperature, a solid sample of Ca(OH)2 is shaken with 0....
*February 22, 2012 by Mahi*

**College Chemistry**

1) The concentration of the aluminum ion in a test solution is 0.10M. Using the Ksp for aluminum hydroxide (3. x 10^-34), calculate the concentration of hydroxide needed to precipitate aluminum hydroxide. From the concentration of the hydroxide, calculate the pH of the ...
*April 1, 2010 by Zach*

**chemistry **

an unknown element crystallizes in a face-centered cubic unit cell. with an edge length of 392.4 pm. The solid has a density of 21.09 g/cm^3. what is atomic weight of solid? so what i did was : FC cubic uit --> 4 atoms edge length--> l = 2*root2*r = 392.4 pm = 392.4 * 10...
*November 8, 2012 by Ania *

**Chemistry**

An element has ccp packing with a face-centered cubic unit cell. Its density is 12400 kg/m3 and the unit cell volume is 5.50 x 10-29 m3. Calculate the molar mass (g/mol) of the element to three significant figures. Please explain how you come to the answer.
*February 9, 2010 by Luc*

**Chem**

A 2.00 M solution of calcium choloride in water has a density of 1.17g/mL. What is the mole fraction of calcium chloride? How do I solve this? I know that density=mass/volume. The mm of calcium chloride is 111g/mol. I don't know how to connect this information.
*April 25, 2008 by Ginger*

**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 ME!!!
*October 27, 2010 by Jessica*

**Thermochemistry, calorimetry**

The density of ice is 0.9168 g/cm3. The density of water is 0.9998 g/cm3. Calculate the difference between ΔU (internal energy) and ΔH (enthalpy) during the fusion of 2.5 moles of ice at atmospheric pressure.
*November 20, 2012 by Peter*

**Chemistry **

In this lab experiment you will make 100.0 mL of a 0.100 M solution of Co(NO3)2. However you must calculate the number of moles of compound that will be needed (moles= Molarity x Liters).Then calculate the mass of Co(NO3)2 that will need to be weighed out (mass= moles x molar ...
*November 19, 2012 by Melissa*

**AP Chemistry**

We were given a 12 cm by 12 cm area of aluminum foil (it weighed 0.60 g) and were told to calculate the atomic mass of Aluminum atoms given that the radius of 1 aluminum atom is 143 picometers and the density is 2.7 grams per centimeter cubed, without using Avogrado's number. ...
*November 15, 2012 by BadatChem*

**physics**

Calculate the total force of the atmosphere acting on the top of a table that measures 1.9 m by 2.3 m.
*January 23, 2012 by B*

**Advanced algebra**

In which distributions does the variable, X, have a binomial distribution? (Choose all that are correct) ~When a 6-sided number cube is rolled 3 times, X is the number of 2s rolled. ~When a 6-sided number cube is rolled, X is the number of times rolled before a 2 appears. ~...
*September 5, 2014 by Alex*

**Advanced algebra**

In which distributions does the variable, X, have a binomial distribution? (Choose all that are correct) When a 6-sided number cube is rolled 3 times, X is the number of 2s rolled. When a 6-sided number cube is rolled, X is the number of times rolled before a 2 appears. When a...
*September 5, 2014 by Alex*

**Notation'**

write 8,350,000 in scientific notation my answer: 8.350 X 10^3
*May 11, 2012 by pls check*

**math**

The perimeter of a triangle is 26 c,. Side a of the triangle is 3 cm longer than side b. Side c is 1 cm shorter than twice side b. Find the length of each side.
*February 4, 2010 by sara*

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