Chemistry

Chemistry
How does the three dimensional structure of SP3 bonds of Carbon, Nitrogen, Oxygen and Fluorine cause them to form polar or non-polar molecules? The answer must include a 3d diagram of the molecules, and a discussion of the effect of their electron configurations for bonds to H...

Chemistry
Why are some solutes soluble in water, but others are soluble in cyclohexane?

chemistry
3. If 15.0 mL of a 1.5M HCl solution at 21.50C is mixed with 25.0mL of a 1.5M NaOH solution at 21.50C that is in a calorimeter, and the final mixed solution temperature rises to 28.50C, what is the ΔHrxn for this process? Assume that Ccalorimeter = 35.5J/0C. a. What is the ...

Chemistry
Explain the most important reason why we have attempted to create a model of the atom and more specifically, why it was so important to understand the position and movement of an electron. These are extra credit questions so I neeeed the points but I'm stumped

Chemistry
The solubility Of KCLO is 33g per dm of water at 70 and 8g per dm of water at 20 calculate the mass of the solute which will crystallize out when 160g of the saturated solution is cooled from 70 to 20

Chemistry
Hydrazine has the formula N2H4 and is used as a rocket fuel (e.g. for the Apollo moon rockets). It burns in the following reaction for which the enthalpy change is -583 kJ/mol. N2H4(g) + O2(g) → N2(g) + 2 H2O(g) Calculate the N-N bond enthalpy in hydrazine given the ...

Chemistry
A compound is 85.6% carbon by mass. The rest is hydrogen. When 10.0 g of the compound is evaporated at 50.0 ∘C, the vapor occupies 6.30 L at 1.00 atm pressure. What is the molecular formula of the compound?

Chemistry
Calculate the molecular mass of sulphur if 35 gram of sulphur dissolves in 100 gram of CS2 to produce a solution that has a boiling point of 49.48°C

Chemistry
If you dilute 19.0 mL of the stock solution to a final volume of 0.350 L , what will be the concentration of the diluted solution?

Chemistry Help
For the reaction 2HI(g) <----> H2(g) + I2(g), Kc = 0.0198 at 721K. What is the HI concentration at 721K if [H2] = 0.120 M and [I2] = 0.0150 M? I'm getting .303 M but that's not one of the options.

Chemistry
Hi! Thanks for checking my question out! ____ 2. Which of the following takes place during a redox reaction? (1 point) a) Electrons are gained only. b) Electrons are lost only. c) Electrons are both gained and lost. d) Electrons are neither gained nor lost. My Answer: C Could ...

Chemistry
At room temperature, 20° C, water (H2O) is a liquid and oxygen (O2) is a gas. Based on kinetic molecular theory, which answer best explains the states of the two fluids? aThe particles in the liquid have greater kinetic energy than the particles in the gas. bThe particles in ...

Chemistry Help
For the reaction 2HI(g) <----> H2(g) + I2(g), Kc = 0.0198 at 721K. What is the HI concentration at 721K if [H2] = 0.120 M and [I2] = 0.0150 M? I'm getting .303 M but that's not one of the options.

Chemistry
bromine has two isotopes Br,79 and Br-81 the relative atomic mass of bromine is 79.9 calculate the percentage or br 79 atoms in a sample of bromine show all working out with all equations used and no abbreviations please

Chemistry
Ytterbium, atomic number, 70 is the first element in the periodic table to have the first four shells full. work out the number of electrons in the fourth shell/ level of ytterbium? Please show all working out with no abbreviations and please help

chemistry
I think it is a trick question as I can not balance this equation . Balance this equation Na(CO3)2+H2SO4=NA(SO4)2+H2O+CO2

AP Chemistry
A 5 gram sample of a gaseous substance occupies 10 L at 48◦C and 697 torr. What is the density of the gas under these conditions? Answer in units of g/L I first started converting the temperature to Kelvin, and the pressure to ATM. I then re-arranged the Ideal gas law to ...

Chemistry
What happens when an electric current is passed through a solution of an ionic compound?

chemistry
What is the mass of BaCl2 contained in 250 mL of solution since after the addition of 40.00 ml of AgNO3 0.1020M to 25.00 mL of the BACl2 solution, the excess solution of AgNO3 consumed 15.00 ml of NH4SCN 0.09800 M

Chemistry
what volume would 1.31g of hydrogen occupy at 2.0atm and 127°c?

Chemistry
How many stereoisomers does [Pt Br4 Cl2]2- have? I think it has 2 geo., but how many optical?

Chemistry
How many stereoisomers does [Pt Br4 Cl2]2- have? I think it has 2 geo., but how many optical?

Chemistry
If one 5 mL dose of Milk of Magnesia contains 400 mg of magnesium hydroxide, calculate the concentration of magnesium hydroxide in mol/L.

Chemistry
Hello this is my first experiment I've ever done before and it was fun but I gotta figure out what NaCl produced and what it yielded in percentage. Can someone double check my work. Na2CO3+2HCl=2NaCl+H2O+CO2 Mass of empty crucible & cover: 33.076g Mass of sodium carbonate used...

Chemistry
A 0.8870-g mixture of sodium chloride and potassium chloride is dissolved in water and silver nitrate is added. The AgCl that precipitates has a mass of 1.913 g. Calculate the percent by mass of potassium in the initial mixture。

Chemistry
calculate the percent deviation from ideal behavior: 1.30 mol N2 in a 2.64-L container at 59 °C exerts 27 bar pressure.

Chemistry
Can someone help me find the grams of what I produced. This is my first experiment I've ever done before and it was fun. Na2CO3 + 2HCl = 2NaCl + H2O + CO2 Empty crucible is: 33.076g I Started with 0.575 Na2CO3 How do I set this up to find how much NaCl that I produced with a ...

chemistry
15. Which of the following (all at STP) will contain the most atoms? (a) 454 L of helium gas (b) 80.00 g of argon gas (c) 454 L of argon gas (d) 80.00 g of helium gas

Physic, maths, chemistry, biology
A body of mass 0.1kg is moving on circular path of diameter 1m at the rate of 10 revolution per 31.4sec, then then centripetal force acting on body is A) 0.2N B) 0.4N C)2N D) 4N

chemistry
How much 10.0 M HNO3 must be added to 1.00 L of a buffer that is 0.0100 M acetic acid and 0.100 M sodium acetate to reduce the pH to 5.05 help please :(

Chemistry
Calculate the volume of 0.5 molar HCl required to titrate 22ml of 0.5 molar Ba(OH)2

Chemistry
Been stumped on this problem for a day now. 2KClO3-->2KCl+3O2 a) If 53.0g of potassium chlorate breaks down, what volume of oxygen is produced? For this one I got: 14.6L O2 b) How many grams of potassium chloride are produced from problem a? For the life of me I can't ...

Chemistry
Hey bob- Here's what I got so far: 3AgNO3 + Na3PO4 ---> Ag3PO4 + 3NaNO3 Silver nitrate and sodium phosphate are reacted in equal amounts of 200. g each. How many grams of silver phosphate are produced? 1. What is the limiting? 2. How much silver phosphate is produced? 3. ...

Chemistry
140 Cal to heat 355 gm of water with initial temperature of 25 degree celsius, final temp?

Chemistry
So i am asked to write the equation representing the third ionization energy for Cr, and what I could come up with is Cr^2+(g)->Cr^3+ + e(not sure if I am right). For the second part I am told that the electron affinity of K is 48 kJ/mol, and i am supposed to write the ...

Chemistry
3AgNO3 + Na3PO4 ---> Ag3PO4 + 3NaNO3 Silver nitrate and sodium phosphate are reacted in equal amounts of 200. g each. How many grams of silver phosphate are produced? 1. What is the limiting? 2. How much silver phosphate is produced? 3. How much is in excess?

Chemistry
Mg + 2HCl ----> MgCl2 + H2 What volume of hydrogen at STP is produced from the reaction of 50.0g of Mg and the equivalent if 75g of HCl? 1. What is the limiting reagent? 2. What is the volume of hydrogen produced? 3. How much is in excess?

Chemistry
H2SO4+2NaOH->2H2O+Na2SO4 How many molecules of water are produced when 12g of sodium sulfate are created? Is this answer correct: 75Lx6.02^23= 452molecules H2O

Chemistry intro
H2SO4+2NaOH->2H2O+Na2SO4 1.) How many grams of H2SO4 are needed to produce 135L of water? 2.) How many molecules of water are produced when 12g of sodium sulfate are created?

Chemistry
H2SO4+2NaOH->2H2O+Na2SO4 1.) How many grams of H2SO4 are needed to produce 135L of water? 2.) How many molecules of water are produced when 12g of sodium sulfate are created?

Chemistry
Why do we use metals in wires? (Select all that apply.) a. Metals are lustrous. b. Metals are reactive. c. Metals conduct electricity. d. Metals are ductile. I think its b and c

Chemistry
write the reaction equation for the formation of CN2H2 (s) from the elements in their standard state.

chemistry
a cylinder filled with a movable Piston contains liquid water in equilibrium water vapour at 25 degree Celsius which one of the following operations result in a decrease in equilibrium vapour pressure

english
Please give feedback, im sorry this is so so long! Many parents struggle to decide on whether they should send their child to a brick and mortar school or online school. For high school students, brick and mortar school is a better option than online school because it includes...

Chemistry
If the molar enthalpy of combustion of ethane is -1.56 MJ/mol, how much heat is produced in the burning of; a) 5.0 mol of ethane b) 45 g of ethane

bio , physics , chemistry , music , English
for the rxn. 2no2 equilibrium to 2 no +o2 kc for that is 1.8 ×10 ki power -6 at 185 degree Celsius at 185 degree the value of kc for no+1÷2o2 equilibrium to no2

Chemistry
Calculate the number of moles of calcium chloride Cacl2 that can be obtained from 25g of limestone CaCo3 in the presence of excess hydrogen chloride

Chemistry
The pH of a solution halfway to the equivalence point

chemistry
What is the condensed formula for 6-chloro-2-methyl-3-heptyne?

Chemistry
2C6H14+19O2 (Arrow)12CO2+14H2O 99.01 g of CO2=..........mol of O2? 188.73g of O2=..............g of C6H14?

chemistry
The combustion of ethane produces carbon dioxide and water. If 27.6 g C2H6 are burned in the presence of excess air (O2) and 76.7 g of carbon dioxide are produced, what is the percent yield?

Chemistry Repost?
Many important metals occur as sulfide, arsenide, and antimonide minerals, especially in the Sudbury mineral complex. The first step in processing these ores involves “roasting” the ore in air to produce the metal or metal oxide, along with nonmetal oxides that can be ...

Chemistry
This is due very soon, please help!!! Describe how you would prepare the following two solutions. Be sure to include the type of glassware which you would use and as much detail as necessary for someone to actually prepare the solution using good laboratory technique. • 250 ...

Chemistry
Calculate the number of molecules in 540cm square of hydrogen gas(H=1,O=16,Avogadro's constant=6.02 x 10 raised to power 23)

Chemistry
Calculate the number of molecules in 4grams of oxygen gas

Chemistry
Describe how you would prepare the following two solutions. Be sure to include the type of glassware which you would use and as much detail as necessary for someone to actually prepare the solution using good laboratory technique. • 250 mLs of a 5% NaCl (w/v) from solid NaCl...

Chemistry
How many electron domains are around the central atom ina water ​molecule?

Chemistry
A sample of oxygen, O2, occupies 32.2 mL at 30 °C and 452 torr. What volume will it occupy at –70 °C and the same pressure?

Chemistry -Assignment Followup
Many important metals occur as sulfide, arsenide, and antimonide minerals, especially in the Sudbury mineral complex. The first step in processing these ores involves “roasting” the ore in air to produce the metal or metal oxide, along with nonmetal oxides that can be ...

chemistry
Most top-loading balances used in this experiment measure a mass only to the nearest mg(+_0.001g).? This significantly affects the calculation of R in this experiment. Explain why this is so. How might the procedure be modified to compensate for this systematic error?

chemistry
What would be the effect on the calculated value of R of each of the following experimental errors? Explain each answer. a. the liquid level in the eudiometer tube is lower than that in the beaker, but this is not taken into consideration in the calculations. b. the balance ...

Chemistry
Please draw a mechanism for the formation of propanal from the oxidation of C18:3 (linolenic acid). Show the pathway for the formation of lipid peroxide and the breakdown of the peroxide via B-scission. I am not interested in side reactions.

Chemistry
What type of atomic orbital has 2 nodal planes?? I got 3d, but would it be just d since nodal planes = angular momentum #??

Chemistry
How would the following affect the calculated value of neutralizing power of antacid (make it higher, lower or no effect)? [The lab uses the back titration technique] 1) The solution mixture of reacted antacid and excess of HCl spattered out the flask during boiling 2) The ...

Chemistry
How many orbitals are in the l = 4 subshell?

Physical chemistry - equilibrium
Ka for ch3coh is 1.8x10^-5. Find out percentage dissociation of 0.2M CH3COOH in 0.1M HCl solution.

Science, Chemistry
A 25.0 mL sample of a 0.0600 M solution of aqueous trimethylamine is titrated with a 0.0750 M solution of HCl. Calculate the pH of the solution after 10.0, 20.0, and 30.0 mL of acid have been added; pKb of (CH3)3N = 4.19 at 25°C. I already calculated pH of the solution after ...

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
Some instruments differentiate individual quanta of electromagnetic radiation based on their energies. Assume such an instrument has been adjusted to detect quanta that have 3.50× 10–16 J of energy. What is the wavelength of the detected radiation? Give your answer in ...

chemistry
What volume of 0.15 mom hclis required to neutralize 25ml of 0.12molar ba(oh)2 solution?

Chemistry
how do i do this? An atom (X) has the following fictitious succesive ionization energies: 745, 1685, 2541, 4425, 7185, 10752, and 27896 kJ/mol. What ion would you expect atom X to make?

Chemistry
how to find approximate effective nuclear charge felt by the valence electrons of an element. please help. thank you

Chemistry
Compute the pH of 1.0x10^-5 M NH4NO3. There was no additional information given.

Chemistry
Identify the longest, shortest, strongest, and weakest bonds? A. H3C-C---C-H B. (H3C-H)>--<(H-CH3) C. (H-H3C)>--<(CH3-H) D. H3C-CH2-(CH-CH3)-CH3

Chemistry Help Please!!!
Which two orbitals overlap to form the sigma bond between C and H in C2HF?

Chemistry
How do I find the molar enthalpy H (kJ/mol) for reaction of NH3 + HCl -> NH4Cl at temp 9.8 celsius by using Hess's Law. I do not understand why there are unknown variables and how to use that to find the molar enthalpy. PLEASE HELP. 1/2 N2 + 3/2 H2 + xH2o -> NH3 H= -80.7...

Chemistry
a) How many orbitals are in the l = 4 subshell? b) The maximum number of orbitals that may be associated with the quantum numbers n = 5 and L = 2 is... I got 9 for both. Kinda guessed Lol. Do you agree?

Chemistry
Hydrogen holds promise as an environment friendly fuel. How many grams of H2 gas are present in a 52.0 L fuel tank at a pressure of 2861 lb/in2 (psi) at 20.0°C? Assume that 1 atm = 14.7 psi.

Chemistry ASAP please?
For electromagnetic radiation with a wavelength of 576.3 nm: (a) What is the frequency of the radiation (in s-1)? (b) What is the energy (in J) of one photon of the radiation? (c) What is the energy (in kJ) of one mole of photons of the radiation So a I go 5.202x10^14 b)3....

Chemistry
Which two orbitals overlap to form the sigma bond between C and H in C2HF?

Chemistry
to make an acid buffer of pH 5, what will be the ratio of salt to acid in the solution. [Ka= 1.8x10^-5 mol.dm^3]

Chemistry
pure phosphene gas 3x10^-2 mol was placed in a 1.5L container. it was heated to 800K. at equilibrium the pressure of CO was found to be 0.497atm. calculate the Kp for the reaction: CO + Cl2 <---> COCl2

Chemistry
at 298K,the vapour of pure water is 23.76mmHg and that of dilute aqueous ultimate urea is 22.9mmHg. Estimate the molarity of the solution

Chemistry
suppose 2.5x10^4g of nitrogen gas and 5x10^5g of hydrogen are mixed and reacted to form ammonia, what is the excess reagent

Chemistry
the equilibrium constant for the reaction N2 + H2 <---> 2NH3 at 700K is 12. calculate the amount of NH3 if the reaction started with 1 mole of N2 and 3 moles of H2 in a 1 liter vessel

Chemistry
7.62g of Fe are allowed to react with 8.67g of S to form brown black iron(III) sulphide at high temp. what is the limiting reagent?

Chemistry
if 2.70 moles of C2H2 is reacted with 6.30moles of O2, calculate the moles of water produced

Chemistry
in the reaction: Cl2 + 2HBr ----> 2HCl + Br2 identify the reduced specie

Chemistry
acetylene gas is produced by adding water to calcium carbide as follows; CaC2 + H2O ---> C2H2 + Ca(OH)2. how many gram of acetylene are produced by adding water to CaC2

Chemistry
The combustion of 0.1572 g benzoic acid increases the temperature of a bomb calorimeter by 2.52°C. Calculate the heat capacity of this calorimeter. (The energy released by combustion of benzoic acid is 26.42 kJ/g.) What is the heat capacity in kJ/C? = 1.65 kJ/C A 0.2197-g ...

Chemistry
The combustion of 0.1572 g benzoic acid increases the temperature of a bomb calorimeter by 2.52°C. Calculate the heat capacity of this calorimeter. (The energy released by combustion of benzoic acid is 26.42 kJ/g.) What is the heat capacity in kJ/C? = 1.65 kJ/C A 0.2197-g ...

Chemistry
I got this as a homework question. Identify Valence electrons and explain the difference in valence orbitals for main group and transition metals. I do not even understand how to begin to answer this. Please help thank you

Chemistry
My teacher asked us the origin of atomic spectra. She did not explain it very well. can someone please explain.Also how do you perform calculations using the Balmer-Rydberg equation? I don't get it. Thank you

Chemistry
Please explain what is the photoelectric effect and how light has particle-like properties? I do not understand.

Chemistry
I dont understand this. please explain the relationship between wavelength, frequency and energy of light waves and the difference between the types of electromagnetic radiation.

Chemistry
What would be the effect on the percent by mass of iron (whether it would be higher, lower or unchanged from what it should be) calculated to be in the unnkown sample and why if the sample contained some Fe3+ as well as some Fe2+

Chemistry
You are trying to find the heat (qrxn) in joules. C is 4.19 Change in temp is -2.2 I don't know how to find the mass if they tell me that the density of the solution is 1.02 and that the volume of water is 100 mL (Should I use the mass of the solution I calculated which was 5....

chemistry
calculate tge pH of a buffer system containing 1.0M CH3COOH and 0.1M CH3COONa

Chemistry
An 8 Molar (aqueous) solution contains H2O and HNO3. The solution has an S.G. of 1.24 at 25oC. HNO3 is a strong acid that completely dissociates in water. a) Calculate the mass of I Litre of solution. b) Calculate the mass concentration (g/L) of HNO3 in solution. c) Calculate ...

Chemistry
What mass of manganese (II) chloride must react with sulfuric acid to release 49.5 mL of hydrogen chloride gas at STP? Mg(s) + H2SO4(aq) -->MgSO4(aq) +2HCl(g)

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