Homework Help: Science: Chemistry

Recent Homework Questions About Chemistry

Chemistry
What is the total ionic and net ionic equation for this aqueous reaction?: Sr(OH)2(aq) + HClO2 (aq) -I wrote the molecular as: Sr(OH)2 (aq) + HClO2 (aq) ---> SrClO2 (aq) + H20 (l) -Is the Total Ionic: Sr2+ (aq) + 2OH- (aq) + H+ (aq) + 2ClO- (aq) ---> Sr2+ (aq) + 2ClO-(aq...

Chemistry
How many aluminum atoms are there in 15.0mg of Al2O3?

chemistry
What is the ∆G for the following reaction under standard conditions (T = 298 K) for the formation of NH4NO3(s)?

Chemistry
Find the Percentage Composition of 0.68g of CaCO3 in 1.3g of antacid tablet. I think it is 680/1300*=approx. 52%

Chemistry
What is the total number of mole of atoms in 1 mole of Al2(CO3)3?

Chemistry
What is the concentration of Pb in mg/L , if you have 25 mg Pb in 5kg of seawater? (note: density of seawater is 1.025 kg/L)

Chemistry
Using the fact that fresh water has a density of 1000 kg/m3 , show that 5ppm Pb = 5 mg/L Pb .

Organic Chemistry
Hello! I was looking for some advice on my organic chemistry lab. We were supposed to separate and identify a solid mixed into a liquid. I found and have confirmed my liquid is acetone by distilling it out of the solid. The solid then turned into a whitish powder while in the ...

Chemistry
rank the compounds below in order of increasing vapor pressure at 298 K? A) c3h6 B) c4h8 C) c5h10

Chemistry
If an astronaut weights 804n on earth what would he weight on a planet that has 3 times the mass and twice the radius of earth

Chemistry (percent abundance) *emergency*
If the average atomic mass of Br is 79.90 amu, what is the percent abundance of each of its isotopes? How would we figure out the isotopes first before we calculate the percent abundance??

Chemistry
4Fe + 3O2 = 2Fe2O3 158g of Fe will react with how many litres of O2 to produce the maximum amount of Fe2O3

Chemistry
A 50.0 mL aqueous solution of sodium hydroxide has a pH of 12.50. If 36.00 ml of 0.0200 mol/L sulfuric acid is added to this sodium hydroxide solution, what will be the new pH of the resulting solution? Assume that the temperature stays constant at 25 C, and that the volumes ...

Chemistry
If 8.87 g of CuNO3 is dissolved in water to make a 0.500 M solution, what is the volume of the solution?

Chemistry
Why do carbonated beverages go "flat" when opened and left and room temperature and pressure?

Chemistry (PLZ HELP)
State why you think clothes might be important to clean in hot water. Is it because it has to do with solubility or something?

chemistry
Hydrochloric acid solution reacts with zinc according to the following equation: 2H3O + Zn -> Zn^2+ + H2 +2H2O 100ml of hydrochloric acid solution Ca=0.5mol/l must be prepared from C=5mol/l hydrochloric solution. 1) Specify the glassware needed for this preparation . At ...

Chemistry
Draw the Lewis Structure of CH3NCS including all resonance forms. Assign formal charges. Do not include resonance arrows.

chemistry
What volume of 0.900 M HCl is required to complete neutralize 50.0 ml of a 0.500 M Ba(OH)2 solution?

Chemistry
This same substance is a gas with a density of 1.25 g/L at 127o C and a pressure of 400 torr. What is its molar mass ?

Chemistry
Ammonium nitrate is an oxidizing agent and can give rise to explosive mixtures of mixture of two moles of powdered aluminum and 3 moles of ammonium nitrate crystals react exothermically yielding nitrogen gas water vapor and aluminum oxide how many grams of the mixture are ...

chemistry
what is the procedure for the preparation of 10 gram of lead iodide

Chemistry
A scintillation counter detects radioactivity by: A) none of the answers. B) emission of light from a NaI crystal when radioactivity passes through the crystal. C) ionization of argon gas in a chamber which produces an electrical signal. D) analyzing the mass and velocity of ...

Chemistry
For the reaction Ag2S(s) ⇌ 2 Ag+ (aq) + S2- (aq), what happens to the equilibrium position if ammonium sulfate is added? A) doubles B) shifts to the left C) does nothing D) shifts to the right E) halves

chemistry
how many grams of sodium hydroxide is required to neutralize 73grams of hydrochloric acid and to form sodium chloride and water

chemistry
The edge of a body-centered-cubic unit cell ( which contains two atoms per unit cell) of an element Y was found to be 2.16x10^-8cm. The density of the metal is 19.35g*cm^-3. What is the approximate molar mass of Y?

Chemistry
I just need someone to check my answers please :) On the pH scale are the following items base, neutral, or acid? 1. Hand Soap 2. Blood 3. Milk 4. Coffee 5. Orange Juice 6. Soda Pop 7. Vomit 8. Battery Acid My answers: 1. Base 2. Neutral 3. Neutral 4. Neutral 5. Base 6. Acid 7...

Chemistry
a+b<->c (fast) c+d->e (slow) e->f+b (fast) How do you determine the overall equation for these reaction mechanisms?

Chemistry
Write a chemical equation for 48g of gasoeous hydrogen and 320g of gaseous oxygen yield

chemistry
Industrial waste contains Zn(II) and cyanide. The waste is toxic to aquatic species like fish. 1- If the waste consists of water, Zn(II) and cyanide, what ligands might complex with Zn(II)? 2- Write chemical equilibria reactions the must be considered to determine toxicity of ...

Chemistry
Identify the equation for which Keq = [Cu+]2[S2-]. A) CuS(s) ⇌ Cu2+(aq) + S2- (aq) B) 1/2Cu2S(s) ⇌ Cu+(aq) + 1/2 S2- (aq) C) Cu2S(s) ⇌ 2Cu+(aq) + S2- (aq) D) Cu2S(s) ⇌ Cu+(aq) + 2 S2- (aq) E) none of the answers

Chemistry
Which of the following is TRUE for a system that is in dynamic equilibrium? A) The forward reaction goes to 100% completion. B) The concentration of products is equal to the concentration of the reactants. C) The reaction rate of the forward reaction approaches zero. D) Both ...

Chemistry
for any solute what important condition must be stated in order to report the solubility answer

Chemistry
Calculate partial pressure given ka1, pH and KH The equation given in the question was: HCO3-(aq)+H3O+(aq)= CO2(aq)+H2O Calculate the partial pressure of CO2. I think you use : [H3O+] = ka1x(antilog pH)/(antilog pH) Then Henrys law: Equilibrium conc.[G]=Kh(law constant) × pg...

Chemistry
Hi , I have this question and I do not know what steps to follow. Please help guide me. It will be really appreciated. Calculate the extent of oxidation in a stream where water it's in equilibrium with atmospheric oxygen and had a pH pic 6.5 (a(H3O+) =antilog (-6.5) ). The ...

CHEMISTRY
what volume of hydrogen is produced with excess HCL according to the equation Zn+2HCL-ZnCL2+H2

chemistry
The edge of a body-centered -cubic unit cell (which contains two atoms per unit cell) of an element Y was found to be 3.16x10^-8cm.The density of the metalis 19.35g*cm^-3. What is the approximate molar mass of Y?

Chemistry
Consider two equally sized balloons at room temperature, one filled with oxygen gas and one filled with an unknown gas. If the balloon filled with oxygen gas deflates in 37 hours and the other balloon deflates in 26 hours, which of the following is the most likely identity of ...

Chemistry
If 2.00 g of element G reacts with 5.00 g of element M to produce 7.00 g of a compound with the formula G3M2, what is the atomic mass of G if the atomic mass of M is 135.0 amu? Answer is 36 amu but why

Chemistry
I am using 85% ACS grade phosphoric acid. I need to make a 21% phosphoric acid solution with a total volume of 250ml. I have been told that 37ml of the 85% ACS grade phosphoric acid plus 188ml of Deionized water will create the 21% phosphoric acid solution I need to make. I'm ...

chemistry
Explain how sodium carbonate can be used to soften hard water

Chemistry
Phosphate can act as buffer: H2PO4- HPO4^2- + H+ The pKa of this equilibrium is 7.21. What is the ratio of H2PO4- to HPO4^2- at pH 7.0? A. 1.62 B. 0.62 C. 50.47 D. 0.019 E. 0.21

chemistry
Please help: How do you prepare 2 L of formate buffer pH=3.14 (c=0.05mol/l) (pk=3.74). THEY WANT THE VOLUMES THANKS

chemistry
A serving of cereal contains 90mg potassium. If there are 22 servings in a box how many moles of Potassium are present in the cereal in the box

chemistry
How many moles of sugar are contained in a 10lb bag of sugar if the sugar has the formula C12H22O11

Chemistry
A is a solution of tetraoxosulphate(iv)acid.B contains 3.95g of sodium trioxocarbonate(iv) in 750cm3 of solution.if 22.70cm3 of the tetraoxosulphate(iv)acid neutralized 25.0cm3 of sodiumtrioxocarbonate(iv).calculate the concentration of i) B in moldm-3 ii) A in moldm-3

chemistry
how many moles are released when 13.2 g of ammonium sulfate 2NH4SO4 is dissolved in water ? I know 13.2 g 2NH4SO4 = .099 moles

chemistry ksp
i feel like none of these answers are right. if the solubility of the solid is 'S' mol/ L, what is the Ksp of the product of the salt? Ca3PO42-(s) --> 3Ca2+(aq) + 2PO42- (aq) A)ksp=S^2 B)ksp=4S^3 C)ksp=27S^4 D)ksp=108S^5 Only leaning towards D because its the only one that ...

chemistry
how do you calculate the equilibrium constant K for a reaction given only the equilibruim pressure for the sample...i thought u needed partial pressures for all substances involved. They just tell me the eq pressure is 3 atm for the sample and ask for Keq. Here's the rxn... ...

AP Chemistry
For the reaction cyclopropane(g) → propene(g) at 500◦C, a plot of ln[cyclopropane] vs t gives a straight line with a slope of −0.00067 s−1 . What is the order of this reaction and what is the rate constant?

Chemistry
1.prepare 2L of 0.150 deci normal aluminum chloride 2.saline solution contains 2grams of its major constituent solute in 1000ml of water.what is it's normality

Chemistry
Equal volume of 3 acids solution with pH 3,4,5 are mixed in a vessel. What will be the hydrogen ion concentration in the mixture ?

Chemistry
The concentration of hydrogen ion in a sample of soft drink is 3.8×10^-3M. Calculate it's pH.

chemistry
Moles chemistry? Calculate the mass of solute required to prepare ib the solution 200cm^3 of solution containig 0.50 mol dm ^-3 cl-iond prepared by dissolving cacl2.6h2o in water.

chemistry
Find the number of moles in 12×10^24 CO2 molecules 1mole is equal to 6.0×10 ^23 ? 12x10^24 Then division of them but the answrr did not match the answer of the book

chemistry
300 milimole of perfect gas occupies 13 lit at 320 k ,calculate the work done in joule ,when the gasexpands A)isothermally against a constant pressure of .20 atm Isothermal and reversible process c)Into vaccum until volume of gas is increased by 3 ltr

Chemistry
1.63 L of an aqueous solution containing 25.00g of KCl dissolved in pure water is prepared. The molarity of the solution is?

Chemistry
The mass of silver produced by thermal decomposition of 5.52g Ag2CO3

chemistry
How many grams of water and how many grams of 85 wt% phosphoric acid would be needed to make 100 grams of 37 wt% phosphoric acid solution?

Chemistry
what is the lowest frequency photon that can ionize a hydrogen atom with excited state electron configuration 3s1

Chemistry
electrons are ejected when a metal is irradiated with 570 nm light. if the wavelength of the ejected electrons is 1.0 nm, what is the work function of the metal? The answer is 1.08 X 10^-19 J, but I dont know how to get here

chemistry
ogen and oxygen react to form nitrous oxide as: 2 N2 (g) + O2 (g) ⇌ 2 N2O (g) Of a mixture of 0.482 mol N2 and 0.933 mol O2 is placed in a reaction vessel of 10.0 L and allowed to from N2O at a temperature for which Kc = 2.0 X 10-37, what will be the composition of the ...

chemistry
A bottle of commercial hydrochloric acid solution So is labeled 37% composition by mass, density 1.19 kg/L. Calculate the concentration of solution So. 4.2 ml of So are diluted to 500ml solution called S. We titrate S with 200 ml of KOH solution of 3×10^-3 mol/l placed in a ...

Chemistry
Draw and repeat unit for a reaction product of glycol: HO-CH2-CH2-CH2-CH2-OH with the following carboxylic acid: HO-C-CH2-CH2-C-OH = = O O

Chemistry
A certain substance has a heat of vaporization of 62.08 kJ/mol. At what Kelvin temperature will the vapor pressure be 4.50 times higher than it was at 361 K? I've gotten it to the point of: ln(4.50)=7466.47423176378616 K (1/361 - 1/T2) Solving for T2 but I don't know where to ...

Chemistry
I just need some ideas of what to put for these on my homework examples for extra credit Name a molecule that has: A) Tetrahedral Geometry B) Trigonal planar geometry C) Linear Geometry D) Bent Geometry

Chemistry
What is tha process of balancing a chemical equation by partial equation method?

Chemistry
You are given 1.226 g of a mixture of KClO3 and KCl. When heated, the KClO3 decomposes to KCl and O2, 2 KClO3 (s) → 2 KCl (s) + 3 O2 (g), and 246 mL of O2 is collected over water at 24 °C. The total pressure of the gases in the collection flask is 755 torr. What is the ...

pmt coching chemistry
25 ml of 3M hno3 are mixed with 75ml of 4.0M HNO3 if volumes are additive then find molarity

Chemistry
What is the ionic compound of SrMnO4

Chemistry
The volume of a sample of a gas collected over water at 32 Celsius and 752 torr is 627 ml. What will the volume of the gas be when dried and measured at STP? (Vapor pressure of water at 32 Celsius = 35.7 torr)

Chemistry
Calculate the new concentration of NaOH if 35 mL of 2.0M NaOH is added to 45 mL of water. If I don't use C1V1=C2V2, then how do I solve it? I'm confuused.

Chemistry
How many milliliters of 2.3 M NaOH are needed to neutralize 4.2 mL of a 5.4 M H2SO4 solution?

chemistry
In a calorimetry experiment, 2.14 g of NH4Cl is dissolved in 100.0 mL of water. The temperature drops by 1.43°C. Calculate the molar heat of solution for NH4Cl.

Chemistry
7.0 mL of 0.64 M HBr reacts with 38 mL of 0.39 M KOH. 1) What are the moles of acid before the reaction? 2) What are the moles of base before the reaction? 3) What is the limiting reagent? 4) How many moles of excess reagent are there after the reaction? 5) what is the ...

Chemistry Help
You are required to make 500 mL of a buffer solution with pH = 5.0 and a total acetate concentration of 0.1000 M. You are supplied with solid sodium actetate (CH3COONa) and 2.00 M hydrochloric acid. What mass of sodium acetate and what volume of hydrochloric acid would you use...

Chemistry
Okay so my lecturer has this in our slides and there are no notes just a heading saying speaciation, I have tried google and everything I have read does not include pH in their question. Please help me Calculate the equilibrium concentrations of the different species in a 0....

Chemistry-Help Please
Help please. Am doing a past exam paper and I hit a road block with this question: Chloride in a brine solution is determined by a precipitation titration. A 10.00 mL aliquot of the solution is titrated with 15.00mL of standard 0.1182 M AgNO3 solution. The excess silver is ...

Chemistry (identifying equations)
What type of reactions are these? Acid-base? Oxidation/Reduction? Precipitation? 1) Zn (s) + 2 HCl (aq) -> ZnCl2 (aq) + H2 (g) 2) Fe (s) + CuSO4 (aq) -> FeSO4 (aq) + Cu (s) 3) Fe (s) + Cu(NO)2 (aq) -> Fe(NO3)2 (aq) + Cu(s)

Chemistry
I just need some ideas of what to put for these on my homework examples for extra credit Name a molecule that has: A) Tetrahedral Geometry B) Trigonal planar geometry C) Linear Geometry D) Bent Geometry

chemistry
find the mass of silver chloride formed from 33.2ml of a 0.100M solution of silver nitrate and 200ml of 0.200M solution of calcium chloride solution Solution plan:use mass to mass calculations mass of AgNO3-moles of AgNO3-moles of AgCl-mass of AgCl 0.1mol/1L*0.0332L+0.200mol/...

chemistry
how does H-bonding affect freezing point depression? I did a lab and calculated my exp molecular weight for benzoic acid and i got a value that is double the known value. My prof said it is due to H-bonding...i don't understand what effect it has on the MW...

Chemistry
Suppose you titrated a sample of sulfuric acid (diprotic acid) with a 0.250 M solution of NaOH. Given the data in the table below, what is the concentration of the sulfuric acid solution?

Chemistry
Calculate the total pressure above 1.0L solution of a 1.42M CH3OH(aq) solution at 25 degrees(C). The vapor pressure of pure methanol at 25 degrees (C) is 127.1 torr and the vapor pressure of the pure water is 23.8 torr at 25 degrees(C. You may assume that the density of the ...

Chemistry
What is the vapor pressure of a solution prepares by dissolving 4.25g of K2O in enough water to preapare 1.25L of Solution at 25 degrees (C)? Assume that the density of the solution is 1.00 g/mL and that the vapor pressure of pure water is 23.8 torr at 25 degrees (C). I've ...

Chemistry
Help please. Am doing a past exam paper and I hit a road block with this question: Chloride in a brine solution is determined by a precipitation titration. A 10.00 mL aliquot of the solution is titrated with 15.00mL of standard 0.1182 M AgNO3 solution. The excess silver is ...

chemistry chem check
Two liquids, 'R' and 'S' form an ideal mixture, what is true about the relation between the mole fraction of R in the liquid phase (X_r) and that of the vapor phase (Y_r) for most mole fractions in the range of 0<X_r<1. A)X_r < Y_r B) X_r > Y_r C)X_r = Y_r D) X_r +...

Chemistry
Calcium carbonate reacts with HCl according to the following equation: 2HCl(aq)+CaCO3(s)→CaCl2(aq)+H2O(l)+CO2​(g) How many moles of HCl are in 58 mL of 0.13 M HCl? What mass of calcium carbonate is needed for complete reaction with the HCl in (a)?

Chemistry
Consider the reaction: Fe2O3+2Al=Al2O3 How many kg of Al2O3 are produced from 25.2 kg of Fe2O3 assuming there is sufficient Al?

Chemistry
Consider the reaction: Fe2O3+2Al=Al2O3 How many grams of Al are necessary to make 100.2 grams of Al2O3?

Chemistry
Consider the reaction: Fe2O3+2Al=Al2O3 How many grams of Fe2O3 Are necessary ro make 100.2 grams of Al2O3? Step by step please.

chemistry
What is the seperation energy ineV for Be3+ in the first excited state in eV?

Chemistry
If a 30.pL tank of laughing gas contains 2.74 moles of N2O at 25 degrees C, what is the pressure (atm) in the tank?

Chemistry
How do orbitals on individual atoms interact and change when covalent bonds form in molecules?

Chemistry (equlibrium direction) urgent
Consider the endothermic reaction 2 NO(g) <-> N2(g) + O2(g) -If I decrease the volume of the vessel and increasing the total pressure in the vessel, what direction will the equilibrium will shift? (left/right) (I know that decreasing the volume would shift to produce ...

Chemistry
A recipe calls for 5M of sucrose (C12H22O11) dissolved in 750mL of H2O. Please calculate the total mass (g) of sucrose needed. Show all work.

chemistry
A major component of gasoline is octane (C8H18). When octane is burned in air it chemically reacts with oxygen (O2) to produce carbon dioxide (CO2) and water (H2O). What mass of oxygen gas is consumed by the reaction of 8.17g of octane?.

chemistry
illustrate how to prepare a 1:3 solution of 0.5 hydrochloric acid

Chemistry
A solution is made by dissolving 55g of KCl in enough water to make 1.00 L of solution. Assume that the density of the solution is 1.00 g/mol. Calculate the mass percent, molarity, molality, and mole fraction of KCl.

chemistry
calculate the mass of butane needed to produce 79.7g of carbon dioxide. express your answer to three significant figures and include the apprppriate units

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Homework Help: Science