Homework Help: Science: Chemistry

Recent Homework Questions About Chemistry

Chemistry
The equation below could be best read as _____. H2(g) + Cl2(g) --> 2HCl(g)

Chemistry
I've been given a table with the following information: Br-Br bonding energy (298 K): 192.807 kJ/mol Br2 vaporization energy: 30.91 kJ/mol boiling point of bromine: 332 K The question reads, "A chemist heats liquid bromine to 335K, and a gas forms. Is the change that occurs a ...

Chemistry
Just to make sure I'm on the right track here, is it correct to say that larger molecules have a higher heat of vaporization/condensation than smaller molecules? I figure that since larger molecules have stronger dispersion forces, it takes more energy for them to break free ...

Chemistry
My teacher wants me to solve this but she/he never thought us how so I need help solving this because I’m kind of confused on what to do and how to do it. 1. Write the correct formulas for the following: A. A compound composed of melt X which has a +2 charge and nonment Y ...

Chemistry - Liquid Methane?
"The planets Uranus and Neptune are so far from the Sun that temperatures are low enough for atmospheric methane, CH4, to condense and form clouds. How is it possible for methane, a nonpolar substance, to exist in this liquid state?" I want to say it's because nonpolar ...

Chemistry
The question on one of my assignments says, "Explain why a thick layer of ice on the lake can support the weight of a person, but the liquid water cannot." I would assume it's because solids are solid and liquids are liquid, but I feel like they want a more scientific answer. ...

Chemistry
13. Solid sodium reacts violently with water, producing heat, hydrogen gas, and sodium hydroxide. How many molecules of hydrogen gas are formed when 48.7 g of sodium are added to water? 2Na + 2H2O = 2NaOH + H2 So far I have this much figured out: Mass to moles for Na: 48.7g Na...

chemistry
Classify the reaction between zinc and acetic acid and explain, in general terms, what happens during this type of reaction. would the type of reaction be a single replacement ??

Chemistry
What is the conjugate base of each of the following? H2SO4 H2CO3 NH3 HF

chemistry
. Classify the reaction between zinc and acetic acid and explain, in general terms, what happens during this type of reaction. would the type of reaction be a single replacement ??

Chemistry
How many unpaired electrons are there in the following transition metal ions in their hexacyano-complex ions? Fe^3+, Pd^2+,CO^2+

Chemistry
What is the conjugate base of each of the following? H2SO4 H2CO3 NH3 HF

Chemistry
What is the mass number for a neutral atom that has an atomic number of 33 and 35 neutrons? How do you get the answer

Chemistry
Write the net ionic equation for the following reaction : Na3SO4(aq) + Ba(NO3)2(aq) —> BaSO4 (s) + 2 NaNO3(aq)

Chemistry
In the 18th century Lavoisier experimented with oxides, such as CO2 and SO2. He observed that they formed acidic solutions. His observations led him to infer that tot exhibit acidic behavior, a substance must contain oxygen. However, today that inference is known to be ...

Chemistry
Using the Krevzi method construct histidine and pyridoxine(Vitamin B6).

chemistry
Calculate the free energy change of the following reaction (in kJ). 3A^2+ +2B------->3A + 2B^3+ Ecell= 1.66 -(5 mol)*(9.65*10^4)*1.66= -8.0095*10^5 Did I do it right? or is the number of electrons wrong?

Chemistry Basic
Hello I understand How to do empirical problems, but the way this problem is worded has me so confused. when 1.00g lithium metal is reacted with fluorine gas, the RESULTING COMPOUND has a mass of 3.73g. Calc the emprical fromula of lithium fluoride. I know for lithium i would ...

Chemistry
Caluculate the molar solubility of PbCl2 in 0.0040 M KI solution. The Ksp of PbI2 - 7.2 x 10^-9. The answer should be 3.29 x 10^-4. This is my work so far PbI2<=====>Pb^+2 + I- PbKI2----->Pb^+2 + KI^-1 7.2 x 10^-9=(s)(s+0.0040M) Assume s<<0.0040 7.2 x 10^-9=(s)(...

Chemistry
Will a precipitate form when 20.0mL of 1.8 x 10^-3M Pb(NO32 is added to 30.0mL of 5.0 x 10^-4M Na2SO4? The Ksp of (PbSO4) is 6.3 x 10^-7.

Chemistry
Will a precipitate of CaSO4 form if 40.0mL of 2.0 x 10^3M CaCl2 is mixed with 60.0mL of 3.0 x 10^-2 Na2SO4?

Chemistry
What is the density of KCl at 25.00 °C if the edge length of its fcc unit cell is 628 pm?

Chemistry
What is the second electron affinity of Se? I believe the first is... Se- -> Se + e- The second.... Se -> Se+ + e-

Chemistry
A 459.1-g sample of an element at 187°C is dropped into an ice–water mixture; 102.5 g of ice melts and an ice–water mixture remains. Calculate the specific heat of the element. ΔHfusion = 6.02 kJ/mol (for liquid water at 0°C).

Chemistry
A 10.0 mL sample of 3.00 M KOH(aq) is transferred to a 250.0 ml volumetric flask and diluted to the mark. It was found that 38.5 ml of this diluted solution was needed to react the stoichimetric point in a titration of 10.0 mL of a phosphoric acid, H3PO4, solution. The ...

General Chemistry
A reaction is run at 20 degrees celsius and takes 30 minutes to go to completion. How long would it take to complete the same reaction at a temperature of 40 degrees celsius? *I believe finding the time has something to do with log? I'm not sure

CHEMISTRY
The solubility of barium sulfate varies with the composition of the solvent. In which one of the solvent mixtures below would BaSO4 have the lowest solubility? i)1.0 M (NH4)2SO4(aq), ii) 0.10 M Na2SO4(aq), iii) pure water, iv) 1.0 M HCl(aq) v) 0.5 M Ba(NO3)2(aq) I have no idea...

General Chemistry
NH4+ + NO2- = N2 + 2H2O A reaction is run, and the liberated N2 gas is collected in a previously evacuated 500 mL container. After the reaction has gone on for 750 seconds, the pressure of N2 in the 500 mL container is 2.77 x 10^-2 atm , and the temperature of the N2 is 250 ...

chemistry
An 0.850 g sample of a mixture of LiH and CaH2 was reacted with H2O and the H2 gas produced, 1.20 L, was collected at STP. What mass % of the original mixture was LiH?

Chemistry
1-1H + 3-1 H yield 4-2 He What is energy in Kj per mole?

Chemistry
What is the ionization constant for a weak acid HA that is 1.60% ionized in 0.095M solution?

Chemistry
The Ka of HClO is 3.0x 10^-8 at 25°c. What is the percent ionization of HClO in a 0.015M aqueous solution of HCLO at 25°c?

Chemistry
Calculate the ratio of the concentration of CO3-2 & HCO3- ions needed to achieve buffering at pH= 9.50. The PkA2 of H2CO3 is 10.25.

Chemistry
How many moles of NH4Cl must be added to 1.5L of 0.2 M solution of NH3 to form a buffer whose PH is 9.(Kb=1.8x10^-5)

Chemistry
if you need 11.2 kg of N2H4 how many grams of H2O2 will be needed?

Chemistry
how many mL of .122 M MnO4- are required to react with an excess of C2O42- in order to produce 75.25mL of carbon dioxide gas measured at 30 degree C and 715 torr?

Science Chemistry
if 4.35 kj of energy are needed to heat a sample of water from 62C into steam at 100.0C what is the mass of the sample

Chemistry
Confused on these, please explain or show work for the answer if you can. :) 1. What is the morality of a water solution that freezes at -0.633°C? 2. What is the freezing point of a solution that contains 1.99 g of a molecular solute of molar mass 58.5 g/mol in 58.0 g water? ...

Chemistry
A 1.00x10-6g sample of nobelium- 254, has a half-life of 55 seconds after it is formed. What is the percentage of nobelium-254 remaining at the following times? (a) 5.0 min after it forms (b) 1.0 h after it forms

Chemistry
Lithium 7 decays losing one alpha particle what is left? 7H 1

CHEMISTRY
Now given that the molar solubility of PbCrO4 (Pb2+ and CrO4 2-) is 1.40 x 10 -8 mol/L, find the Ksp

CHEMISTRY
Find the expression for the solubility product of silver oxalate Ag2C2O4).

CHEMISTRY
The solubility of Ag2NtO4, silver nortonate, in pure water is 4.0 x 10-5 moles per liter. Calculate the value of Ksp for silver nortonate.

CHEMISTRY
2) Find the expression for the solubility product of silver oxalate Ag2C2O4).

science
someone please help with this chemistry question. Describe what happened when Ag+ combined with Na^2CO^3. What does this indicated?

chemistry
Consider the following reaction in the solvent CCl4 in a 1-L flask: 2IBr(g)<->Br2(g)+I2(g) What is the equilibrium moles of IBr, Br2 and I2 are 0.2, 0.1 and 0.1, calculate the equilibrium constant Kc.

AP Chemistry
If the heat of combustion of 1-butanol (C4H9OH) is 2,710 kJ/mol, what mass of oxygen is consumed when enough 1-butanol is burned to yield 26,400 kJ of energy? I have no clue where to begin I thought to use enthalpy but it didnt work

Chemistry
Using the following bond energies, calculate the molar heat of hydrogenation, ΔHhydrogenation, for the conversion of C2H2 to C2H6 CH (triple bond) CH (g) + 2H2 (g) --> CH3CH3 (g)

chemistry
19.4 g of butane (58.12 g/mol) undergoes combustion according to the following equation. What pressure of carbon dioxide in atm is produced at 309 K in a 1.15 L flask. 2 C4H10 (g) + 13 O2 (g) → 8 CO2 (g) + 10 H2O (g)

AP Chemistry
If the heat of combustion of 1-butanol (C4H9OH) is 2,710 kJ/mol, what mass of oxygen is consumed when enough 1-butanol is burned to yield 26,400 kJ of energy? I have no clue where to begin I thought to use enthalpy but it didnt work

Chemistry As
Calculate the molar mass in gmol-1 of h3x.nh20 mass:2.07g volume:21.35 there are 2 equations for concentration: n(h3x.nh20)=c(h3x.nh20) x 250cm3/1000 n(h3x.nh20)= c(h3x.nh20) x 21.35/1000 multiply both sides and make the concentration the subject shpowing every singe step and ...

chemistry
determine the number of grams of Ne gas that must be added to a container in order for the volume to increase to 38.2 L at constant pressure and temperature if the container had an initial volume of 25.0 L and 2.0 moles of Ne

Chemistry
If 17.7 kJ are released when 1.00 g of O2 reacts with an excess of NO, complete the thermochemical equation below. 4 NO(g) + 3O2(g)=2 N2O5(g) ΔHrxn = ___KJ

Inorganic Chemistry
Which one is more stable, [PCl4]+ or [PCl6]- ? Why? I'm thinking it has something to do with the fact that the former is tetrahedral and the latter is octahedral, but I'm not sure. Does that affect stability?

Chemistry
What is saponification (soap making) ?

Chemistry
A solution contains 2.2×10−4 M Ag+ and 1.3×10−3 M If NaI is added, will AgI(Ksp=8.3×10−17) or PbI2(Ksp=7.9×10−9) precipitate first? I know the answer to this is AgI Specify the concentration of I− needed to begin precipitation.

Chemistry
If 0.370 g of Ca(OH)2 is added to 500 mL of water and the mixture is allowed to come to equilibrium, will the solution be saturated?

chemistry// organic
What type of reaction forms an alkaloid salt? a. The reaction between an amine and an alcohol. b. The reaction between an amine and an acid. c. The reaction between an alcohol and a base. d. The reaction between an amine and a base. e. The reaction between an alcohol and an acid

chemistry// organic
This is a pushing question. We discussed how phenols are typically more acidic than alcohols, even though they both contain the same hydroxyl functional group, because phenols possess an aromatic ring that delocalizes the negative charge after a proton is removed. Consider the...

Chemistry
Which of the labeled sections in the below molecule would be considered an unsaturated portion of the molecule? A) \ B)|| C) | \\\ /\ /|\ \ a. A and B b. B only c. C only d. B and C

Chemistry
Why do heteroatoms help determine the physical and chemical properties of a molecule? a They forms more bonds to other atoms than carbon can. b They possess nonbonding pairs of electrons and affect the molecule’s polarity. c They possess stronger bonds with hydrogen atoms ...

Chemistry
What is the name of the below organic compound? | \ \ | | \/\/\/ This is kind of what it looks like sorry this looks so horrible the image would not copy over. a 1,1,3-triethylhexane b 3-ethyl-5-propylheptane c 3-propyl-5-ethylheptane d 3,5-diethyloctane

Chemistry (organic)
What is the molecular formula for the below line-angle structure? The structure is a pentagon with one line connected to a corner. I'm sorry if that doesn't make any sense but the picture will not paste here. a C6H11 b C5H11 c C7H12 d C5H13 e C6H12 Thank you so much in advance!!

Chemistry
29.25g of sodium chloride is added to water and undergoes electrolysis according to this equation 2Cl-=Cl2 Calculate the mass of chlorine produced. I am lost with this one !

Chemistry
Glucose( C6H12O6) is produced by photosynthese. For every kilo of water the plant takes in ,how much glucose can it make ? I done the balanced equation wich is (I think) 6H2O+6CO2 = C6 H12 3O6 After that I get a ratio of 108/372 wich give me a tota of 3444 grammes of glucose ...

Chemistry
1. HCl(aq)+KOH(aq)→KCl(aq)+H2O(l) Express your answer as a net ionic equation. Identify all of the phases in your answer. 2. 2HC2H3O2(aq)+Ca(OH)2(aq)→Ca(C2H3O2)2(a​q)+2H2O(l) Express your answer as a net ionic equation. Identify all of the phases in your answer.

Chemistry
Given the reactant side of the total ionic equation for the neutralization reaction of ammonium hydroxide (NH4OH) with hydrochloric acid (HCl), write the total ionic equation (also known as the complete ionic equation) by entering both the reactant and the product species, ...

Chemistry
H2CO3(aq)+Ba(OH)2(aq)→ Express your answer as a chemical equation. Identify all of the phases in your answer

Chemistry
What kind of reaction is it when you put a potato in hydrogen peroxide?

Chemistry
H2O2 → H2O + O2 is this a balanced equation?

Chemistry 131
4.0g of an unknown potassium halide (KX, where X is the halide) is dissolved in 100g of water. The solution freezes at -1.28 degrees Celsius. What is the identity of the halide?

Chemistry
What is the maximum amount of water (in grams) that can be produced given 4 moles of hydrogen and 4 moles of oxygen?

Chemistry
If 4 moles of hydrogen react with 4 moles of oxygen which of these is the limiting reagent?

chemistry
Does N2O violates the octet rule?

Chemistry
Which is the strongest interparticle force present in a sample of H3PO4? ion―dipole forces dipole―induced dipole forces hydrogen bonding forces ionic bonding forces ion―induced dipole forces dispersion forces dipole―dipole forces

Chemistry
What is the chemical equation for solid aluminum reacts w/ solid iodine to produce solid aluminum iodide?

chemistry
Does N2O violates the octet rule?

chemistry
DOES NO-3 VIOLATES OCTET RULE ?

Chemistry
In a solution of .200M NaI, solid AgI was placed in. Calculate the solubility if AgI (Ksp=1.5*10^-16)

Chemistry
The volume of a balloon is 1 liter at 1 atm pressure and 0°C temperature. What volume is the ballooon at 2 atm pressure and 273°C temperature?

Chemistry
Calculate the volume of 1.86M Na3PO4 solution that can be prepared from 5.45 g of Na3PO4

chemistry
The normal boiling point of liquid butanol is 391 K. Assuming that its molar heat of vaporization is constant at 45.9 kJ/mol, the boiling point of C4H9OH when the external pressure is 0.647 atm is

Chemistry
Consider separate 1.0-L samples of He (g) and UF6 (g), both at 1.00 atm and containing the same number of moles. What ratio of temperatures for the two samples would produce the same root mean square velocity? T UF6/T He= x/1.0

Chemistry
Ca(OH)2 has a Ksp of 6.5×10−6. If 0.370 g of Ca(OH)2 is added to 500 mL of water and the mixture is allowed to come to equilibrium, will the solution be saturated?

ChEmIsTrY
Alpha rays are really a. electrons b. helium nuclei c. electromagnetic waves I think the answer is B because the alpha particle is a helium nucleus. But I'm confused because if the alpha PARTICLE is a helium nucleus, would alpha RAYS be helium nuclei? Please explain.

Chemistry
Road map in chemistry ?

Chemistry
A 0.3146-g sample of a mixture of NaCl(s) and KBr(s) was dissolved in water. The resulting solution required 37.20 mL of 0.08765 M AgNO3(aq) to precipitate the Cl–(aq) and Br–(aq) as AgCl(s) and AgBr(s). Calculate the mass percentage of NaCl(s) in the mixture.

Chemistry
If the concentration of I^-1 is found to be 2.4x10^-3 mol/L in a saturated solution of PbI2, what is the Ksp of PbI2? The given answer is 6.9x10^-9

Chemistry
A 1.80-g sample of water contains _____ mole(s) of hydrogen atoms.

Chemistry
Is a mole of marshmallows is 6.022 X 10^23 true or false? I think it is false but I'm not sure.

CHEMISTRY
Exactly 3.0 mol NO and 2.0 mol O2 were placed in a 1.00-L flask. These gases react as follows: 2 NO + O2 2 NO2 . At equilibrium, the mixture contained 2.0 mol NO2. What is the Kc for the reaction above? A 0.50 B 1.00 C 2.0 D 2.5 E 4.0

College Chemistry
Please help I have no idea how to do this. There are three different dichloroethylenes (molecular formulaC2H2Cl2), which we can designate X, Y, and Z. Compound X has no dipole moment, but compound Z does. Compounds X and Z each combine with hydrogen to give the same product: ...

Chemistry
Please help I have no idea how to do this. There are three different dichloroethylenes (molecular formulaC2H2Cl2), which we can designate X, Y, and Z. Compound X has no dipole moment, but compound Z does. Compounds X and Z each combine with hydrogen to give the same product: ...

Chemistry
Blueprint paper can be made by soaking paper in a brown solution of Fe(CN)6^3- and iron (III) ammonium citrate. Wherever the paper is exposed to bright light, the paper turns blue. Explain why this happens.

Chemistry
1. I am making holiday cookies and the recipe says that it will make 48 cookies. After eating some raw cookie dough I bake the remainder into cookies and am able to make 44 cookies. what is the percent yield?

Chemistry
you reacted magnesium with a hydrochloric acid aqueous solution and hydrogen gas was produced. Let's say that you collected the gas given off by the reaction and measured it's pressure as 102.1 kPa. If the vapor pressure of water is 16.2 kPa at this temperature, then what is ...

Chemistry
(I corrected it ) 1. Sodium and water react according to the following equation. If 31.5g of sodium are added to excess water, how many liters of hydrogen gas are formed at STP? 2Na+2H2O—>2NaOH+H2 My work: For #1 Na would have 2 moles and H would have 1? Make 31.5g x 2/1=...

Chemistry
In my titration method it says trial titration. In my table it says rough titration. I know the meaning of both. But, are they the same thing and could i say my first titration rough value is both the trial titration and rough titration?

Chemistry
PART A) Suppose that 6.9 mL of 2.5 M KOH(aq) is transferred to a 250 mL volumetric flask and diluted to the mark. It was found that 32.8 mL of this diluted solution was needed to reach the stoichiometric point in a titration of 6.9 mL of a phosphoric acid solution according to...

chemistry
Calculate the mass CaCl2 · 6 H2O needed to prepare of 0.123 m CaCl2(aq), by using 373 g of water. Answer in units of g.

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Homework Help: Science