coffeetrout614

 A 30.00 L air sample was passed through an absorption tower contained a solution of 
Cd2+
, where H2S was retained as CdS. The mixture was acidified and treated with 10.00 
mL of 0.01070 M I2. After the reaction, 
S
2- + I2 S(s) + 2I- was complete, the excess iodine was titrated with 12.85 mL of 0.01344 M thiosulphate. 
Calculate the concentration of H2S in ppm; use 1.20 g/L for the density of gas stream.

 The mean activity coefficients of HBr in three dilute aqueous solutions at 25° C are 0.930 (at 5.0 mmol kg-1), 0.907 (at 10.0 mmol kg-1), and 0.879 (at 20.0 mmol kg-1). Estimate the value of B in the extended Debye-Hückel law, with C = 0

Balance the following: 

(b)   

1. 1. After a dose of 500 mg of drug X, Vd=40L, Kel=0.1 hr-1,
   a. CalculateCpafter4hr.
   b. What is the half-life of the drug.
   c. When will the drug be completely eliminated?
   d. How many half-lives will the drug take when 50 mg of it remain in the body?

What is the molar mass of ammonium sulfate?

What is the molar mass of ammonium sulfate?

what is the molar mass of ammonium nitrate?

what is the formula mass of ammonium nitrate?

What is the Formula mass of Ammonia?

What is the formula mass of ammonia?

What is the formula mass of CuSO₄?

What is the formula mass of water?

What is the formula mass of water?

What is the formula mass of ?

Which is the first step in writing a summary?

A. prewrite 

B. draft

C. revise

What is the formula?

(b) Calculate the mass in grams of phosphorus in 0.414g of  

(c) What percentage of the daily value of phosphorus comes from this tablet?

1. Sketch the followings Miller indices within a cubic unit cell: (021) [333]؟

What kind of energy is chemical energy?

What kind of energy does an unlit match have?

Solve

Two light sources are used in a photoelectric experiment to determine the work function for a particular metal surface. When green light from a mercury lamp (𝜆 = 546.1 nm) is used, a stopping potential of 0.838 V reduces the photocurrent to zero.

Please answer a and c 

Calculate the energy of a photon having a wavelength in the following ranges.

Find the mass of the precipitate that is formed by the reaction of 50 grams of copper (II) chloride with an excess of potassium hydroxide.

(a) If the wavelength of an electron is 4.63 ✕ 10−7 m, how fast is it moving?
 km/s

(b) If the electron has a speed equal to 8.20 ✕ 106 m/s, what is its wavelength?
 m

(a) An electron has a kinetic energy of 6.00 eV. Find its wavelength.
 nm

(b) A photon has energy 6.00 eV. Find its wavelength.
 nm

In a photoelectric experiment, a metal is irradiated with light of energy 6.56 eV. If a stopping potential of 1.04 V is required, what is the work function of the metal?
 eV

State the law of conservation of energy in a complete sentence.

How does a catalyst speed up a chemical reaction?

◯ A. by lowering the activation energy

◯ B. by lowering the △H of the reaction

◯ C. by raising the energy of the products

◯ D. by raising the energy of the reactants

 EDTA is the most common titrant used in complex-formation titrations. What does EDTA stand for and  what type of ligand ? 

A. ethylenediaminetetraacetic acid // tetradentate ligand 

B. ethylenediaminetetraoxalic acid // tetradentate ligand 

C. ethylenediaminetetraacetic acid // hexadentate ligand 

D. ethylenediaminetetraoxalic acid // hexadentate ligand 

Above is rendered the structure of Xarelto, a commonly prescribed anticoagulant used in the management of deep vein thrombosis (DVT aka "blood clots").

a. Indicate any stereogenic centers with an asterisk (2)

b. Determine the absolute stereochemistry of any stereogenic center (2)

c. Draw the structure of enantiometer of Xarelto and indicate the absolute stereochemical configuration (6)

d. How may diastereomers of Xarelto exist? Draw them and indicate their absolute stereochemical configuration (4)

e. Circle and label two functional groups in Xarelto (6)

f. Provide FTIR spectral characteristics for the FG you indicated in part (e) (6)

1. The dimensions of a rectangular box are given to be 10.2 cm x 43.7 cm x 9.562 x 10 mm. What is the volume in liters?