Mahnoor

This page lists questions and answers that were posted by visitors named Mahnoor.

Questions

The following questions were asked by visitors named Mahnoor.

The standard enthalpy of formation of H2O (l) is -285.8 kJ/mol. Calculate DEO for the following reaction. H2O (l) → H2 (g) + 1/2 O2 (g)

In order to calibrate a bomb calorimeter , 3000 g of water is added to the calorimeter. next, 1.08 x 10-2mol of ethanol (C2H6O) is combusted in the presence of excess oxygen according to the equation, C2H6O (l) + 3 O2 (g) > 3 H2O (l) + 2 CO2 (g) DE = - 13...

Suppose that 1.048 g of benzene is combusted in a bomb calorimeter which contains 945 g of water. The temperature of the water increases from 23.640 OC to 32.681 oC. The heat capacity of the empty calorimeter is 891 J/ OC . C6H6 (l) + 15/2 O2 (g) > 3 H2O...

Consider the following reaction AgNO3 (aq) + NaCl (aq) → AgCl (s) + NaNO3 (aq) DH = -66 kJ Suppose that 100.0 mL of 0.100M AgNO3 is added to 200.0 mL of 0.100 M NaCl in a coffee cup calorimeter. Assuming that the initial temperature of the solution is 25....

Suppose that 50.0 mL of a 0.250 M HCl solution is mixed with 50.0 mL of a 0.100 M Ba(OH)2 solution in a coffee-cup calorimeter. The temperature of the resulting solution increases by 1.76 oC . Calculate DH for the reaction between HCl (aq) and Ba(OH)2 (aq...

Suppose that 0.205 g of a mixture containing Na2SO4 and K2SO4 is dissolved in water. An excess of BaCl2 is added and a precipitate of 0.298 g of BaSO4 is produced. Calculate the percent by mass of Na2SO4 and K2SO4 in the original mixture.

While I3- and Br3- are both stable molecules F3- is not a stable molecule. Provide an explanation.

Consider the Li2+ ion. (a) Calculate the wavelength of light emitted when the electron jumps from the n=4 level to the n=2 level. (b) What is the ionization energy of Li2+ ?

The ionization energy of Fe is 434 kJ/mol. What is the maximum wavelength of light capable of ionizing Fe? What type of light is this?

Give the maximum number of electrons in an atom that can have the following set of quantum numbers. (a) n=4 (b) n = 5, ml = 1, (c) n = 5, ms = 1/2

What is the maximum number of orbitals in an atom that can have the following designations? (a) 5p (b) 2pz (c) n=4

estimate Delta H for the following reaction C2H4 (g)+3O2(g)→2 CO2(g)+2 H2O(g) So we have (4) C-H bonds and (1) C=C bond or (H = 4*414 + 615= 2271) For oxygen, (3) O=O bonds or (H = 3*502=1506) 2CO2 is (2) O=C=O (H=730*4=2920) 2H2O is (2) H-O-H or (H=4*464...

Find inverse of f if f(x)= x^2-4x+3, (for x is smaller than and equal to 2). First prove that f(x) is one to one in the defined domain of f and then obtain the inverse function. I know how to find the inverse. We just switch x and y. so y=x^2-4x+3 becomes...

The rate constant for the decomposition of gaseous azomethane, C2 H6 N2 (g) > N2 (g) + C2 H6 (g) Is 40.8 min-1 at 425OC. Find the number of moles azomethane and the number of moles of nitrogen 0.0500 minutes after 2.00 g of azomethane is introduced. Assum...

A 1.0 x 10-2 M solution of a weak acid is found to be 3.7% dissociated. Calculate Ka of this acid. I found the amount dissociated by (amount dissociated/initial conc)*100=3.7 Where do I go from here?

in todays experiment what length of magnesium ribbon would be required to generate 42.00 ml's of H2?

Solve for x: x – 4(2x – 1) ≥ 2(x – 1)

Answers

The following answers were posted by visitors named Mahnoor.

You mean 9.6*10^7/1.5*10^-2? If yes the answer is 6.4*10^9

I'm explaining for HI03 First we assign oxidation numbers to Oxygen and Hydrogen then to any other atom. So oxygen is -2*3 and H is +1. So now let I's oxidation number be x. +1+x+(3*-2)=0 (0 because the overall compound has 0 charge) +1+x-6=0 x-5=0 x=5

Agyee ka solution nai hay na upper walay question may