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• What are the ways in which the rate of a chemical reaction can be changed?
  
• Use half-cell potentials to calculate #K_(eq)# for the reaction below?
  
• How does the atomic radius change from top to bottom in Groups 1 and 2?
  
• A gas occupies a volume of 250 centimetre Cube 745 torr and 25 degree Celsius what additional pressure is required to reduce the gas volume to 200 cm cube at same temperature?
  
• Why should I use significant figures in chemistry?
  
• )An Aeresol can with a volume of 325 mL contains gas at 445kPa at 12ºC. What volume would the gas occupy if it was allowed to escape at 101 kPa and 21ºC? (Answer is 1.5 x 10^3 mL) No matter what I try I can't get the answer right
  
• What color is bromcresol green after it is added to a sample of #NaOH(aq)#?
  
• Nitrogen gas and hydrogen gas combine to produce ammonia gas. Write a balanced chemical equation for this reaction?
  
• A sample of Freon-12 (#CF_2Cl_2#) occupies 25.5 L at 298 K and 153.3 kPa. How do you find its volume at STP?
  
• Nuclear Chemistry and Half-life calculations?
  
• Consider a weak acid #"HA"#, where #"A"^(-)# is some arbitrary anion and #"HA"(aq) + "H"_2"O"(l) rightleftharpoons "H"_3"O"^(+)(aq) + "A"^(-)(aq)#. Suppose you add some #"NaA"(s)# to #"H"_2"O"(l)#. What is the pH of the solution?
  
• A solution of protein (extracted from crab) was prepared by dissolving 0.75g in 125ml of a solution. At 4°C an osmotic pressure rise of 2.6 mm of the solution was observed. Then molecular mass of protein is (assume density of solution is 1gm/ml) ?
  
• The temperature of a gas is T1 and the original pressure is P1. The temperature of the gas is changed to T2. Which of the equations below would you use to find the new pressure (P2)?
  
• How would you find atomic mass?
  
• A solution contains 85.0g of NaCl, and has a volume 750mL. What is the molarity of the solution?Molar mass of NaCl=58.44g/mol
  
• What is the ¥w for pure water and for solution and for solute or water pot for solution with more solute present will be :?
  
• What would be a possible ph for a 0.10 M solution of acid?.
  
• Given that, Magnesium's one atom's mass is 4.03463*10^-23 g. What is the relative atomic mass of magnesium?
  
• Only 235U can be used as fuel in a nuclear reactor, so uranium for use in the nuclear industry must be enriched in this isotope. If a sample of enriched uranium has an average atomic mass of 237.662 amu, what percentage of 235U is present?
  
• What is the concentration in molarity of S2O32- (aq) in a solution prepared by mixing 300 mL of 0.162 M Na2S2O3 (aq) with enough 0.126 M KCl (aq) to make a 350.0 mL solution? (Assume volumes are additive and that no chemical reactions take place.)
  
• A 400 mL sample of oxygen is cooled from 0°C to -40°C. What is the new volume of oxygen? (Assume that the pressure and number of moles has not changed.)
  
• Calculate the amount of energy evolved (in kJ) when 2.50 mg of 2H undergoes fusion according to the equation below. 2H + 3H = 4He + 1n ?
  
• Why is the normal boiling point of a liquid the point at which the vapor pressure is equal to atmospheric pressure, #"760 torr"#?
  
• Chlorine gas + aqueous calcium iodide produces what?
  
• How do we choose suitable indicator for titration of weak acid with strong base?
  
• Question #ccc4f
  
• Question #7f216
  
• Question #01c42
  
• How do chemists use the ideal gas law?
  
• An air sample contains 0.038% #CO_2#. If the total pressure is 758 mm Hg, what is the partial pressure of #CO_2#?
  
• Question #60360
  
• How do you calculate the ionization energy of an element?
  
• Question #dd295
  
• Question #e3d2a
  
• What is the Lewis Dot Structure of (CH3)2SeCl2?
  
• Why is there an empty #p# orbital in #"Al"# of #"AlCl"_3?#
  
• Question #50273
  
• Question #2334a
  
• Question #cbc8b
  
• How do you determine if a molecule is linear?
  
• For the atomic shell with quantum number n = 1, how many sub-shells are possible where each sub-shell has a different value of the angular momentum quantum?
  
• What is the Lewis structure of #"nitrosyl chloride"#, #NOCl#?
  
• Question #9e3a5
  
• Which one of the elements with following outer electronic configurations may exhibit the largest number of oxidation states?
  
• What is the balanced net ionic equation for the reaction in acidic solution of #Fe^(2+)# and #KMnO_4#?
  
• For the equilibrium reaction X + y -> XY, the rate of the forward reaction at equilibrium is equal to 1.75 sec^(-1). What is the rate of the reverse reaction?
  
• Among the following which is not paramagnetic?
  
• What are #"normality"# and #"molality"# for a #"36% (m/m)"# solution of hydrochloric acid, that has #rho_"solution"=1.180*g*mL^-1#?
  
• Question #01511
  
• Question #a6b05
  
• Question #66d23
  
• Question #2b76b
  
• Question #b2f7a
  
• Question #7309a
  
• Question #0124f
  
• Question #43d6b
  
• Question #d3d97
  
• Question #a2918
  
• The standard heat of formation of Fe2O3(s) is 824.2kJ/mol. Calculate heat change for the reaction 4Fe(s)+3O2(g)=2Fe2O3(s)?
  
• What information does the chemical equation #2C_4 H _10+13O_2 -> 8CO_2 + 10H_2 O# provide?
  
• At a pressure 47 kPa, the gas in a cylinder has a volume of 12 liters. Assuming temperature remains the same, if the volume of the gas is decreased to 8 liters, what is the new pressure?
  
• Question #be093
  
• Question #3790f
  
• How do you calculate boiling point at different pressures?
  
• What is the heat absorbed by #"27 g"# of water that increases in temperature by #58^@ "C"#? Assume #c = "4.184 J/g"^@ "C"# for water in this temperature range.
  
• Iron-59 has a half-life of 45.1 days. How old is an iron nail if the Fe-59 content is 25% that of a new sample of iron? Show all calculations leading to a solution.
  
• ( In a tube ) why CO2 gas doesn't sinks (gets below) , displacing the water to be on the top, If carbon dioxide (44 g/mol) has more molar mass than water( 17 g/mol)? Is it just because water is a liquid and co2 is a gas or there are some other factors?
  
• Question #19ea5
  
• Question #d0d5a
  
• How does concentration affect galvanic cell?
  
• Question #e175e
  
• What is the factor that is measured during an experiment?
  
• Question #9371c
  
• What is the half-life of a radioactive isotope if a 500.0 g sample decays to 62.5 g in 24.3 hours?
  
• What is the Ksp equation?
  
• What is the molecular geometry, or shape, of chloroform #CHCl_3#?
  
• Question #471de
  
• Question #a87b0
  
• Question #4b2ef
  
• A compound is found to consist of 63% manganese and 37% oxygen by mass. What is the empirical formula?
  
• A substance has a mass of 360 g and a volume of 7.5 #cm^3#. What is its density?
  
• What is the mole fraction of #LiCI# in a mixture of 0.564g #NaCl#, 1.52g #KCl# and 0.857g #LiCI#?
  
• How do you calculate the Ka of an acid?
  
• How do you determine the binding energy of lithium-6?
  
• Q.)(i) How many moles of sulphur will be produced when 2 moles of H2S reacts with 11.2L of SO2at NTP?
  
• In the Lewis dot structure for #NH_3#, the central atom of the molecule has three atoms bonded to it and one lone pair of electrons. What is the shape of an #NH_3# molecule?
  
• Question #eb9b7
  
• Question #ee6cb
  
• What is the mass of one mole of carbon dioxide?
  
• Question #69245
  
• Have we ever used #""^56 "Co"# for any interesting industrial purpose(s)? Cite any sources you may find on this.
  
• How can you calculate an empirical formula?
  
• Can the Henderson-Hasselbalch equation be used to estimate the pH values at the equivalence point?
  
• Phosphorus burns in air to produce a phosphorus oxide in the following reaction. What mass of phosphorus will be needed to produce 3.25 mol of #P_4O_10#? If 0.489 mol of phosphorus burns, what mass of oxygen is used? What mass of #P_4O_10# is produced?
  
• How can you get determine an atomic number?
  
• Can the Henderson-Hasselbalch equation be used to estimate the pH values at the equivalence point?
  
• What properties describe how substance interact with other?
  
• What does the phase diagram of water look like?
  
• What does the compound #ClF# contain?
  
• What is required for a chemical reaction to occur?
  
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