How many elements make up this compound C7H5(NO2)3

How does the rate of reaction proceed with time

Studentka2010 [4]

It is the speed of light

6 0

3 years ago

25 g of a compound is added to 500 mL of water if the freezing point of the resulting solution is

vlabodo [156]

Answer:

a) 119 g/mol

Explanation:

-We apply the formula for freezing point depression to obtain the molality of the solution:

$\bigtriangleup T_f=K_fm, \ \ K_f=1.36\textdegree C/m\\\\\therefore m=\frac{\bigtriangleup T_f}{K_f}\\\\=\frac{0.57\textdegree C}{1.36\textdegree C}\\\\=0.4191\ mol/Kg\\\\$

#We use the molality above to calculate the molar mass:

$m=\frac{0.4191\ mol}{1\ Kg}=\frac{25\ g}{0.5\ Kg}\\\\\therefore 1 \ mol=\frac{25\ g}{0.5\ Kg}\times\frac{1\ Kg}{ 0.4191}\\\\=119.3033\approx 119\ g/mol$

Hence, the molar mass of the compound is 119 g/mol

5 0

4 years ago

42.9 liters of hydrogen are collected over water at 76.0 °C and has a pressure of 294 kPa. What would the pressure (in kPa) of t

BabaBlast [244]

Answer:

494.1 kPa

Explanation:

Using the combined gas law equation;

P1V1/T1 = P2V2/T2

Where;

P1 = initial pressure (kPa)

P2 = final pressure (kPa)

V1 = initial volume (L)

V2 = final volume (L)

T1 = initial temperature (K)

T2 = final temperature (K)

According to the information provided in this question,

P1 = 294 kPa

P2 = ?

V1 = 42.9 liters

V2 = 22.8 liters

T1 = 76.0°C = 76 + 273 = 349K

T2 = 38.7°C = 38.7 + 273 = 311.7K

294 × 42.9/349 = P2 × 22.8/311.7

12612.6/349 = 22.8 P2/311.7

36.14 = 22.8P2/311.7

Cross multiply

36.14 × 311.7 = 22.8P2

11264.605 = 22.8P2

P2 = 11264.605 ÷ 22.8

P2 = 494.1 kPa

3 0

3 years ago

Calculate the average reaction rate expressed in moles h2 consumed per liter per second

djyliett [7]

Answer:

Average rate of reaction expressed in moles H₂ consumed per liter per second = 0.0025 M/s = 0.0025 mol/L.s

Explanation:

The complete, correct Question, is presented in the attached image to this answer.

The average rate of reaction in terms of the reactant is defined as the total amount of reactant consumed over a period of time divided by total period of time.

Mathematically,

Average rate of reaction = (change in concentration of H₂ over a period of time) ÷ (total period of time)

Average rate of reaction = (-ΔC)/(Δt)

The minus sign is there because the concentration of reactants reduce with time.

change in concentration of H₂ = -ΔC

= -(0.02 - 0.03) = 0.01 M

Time = Δt = 4 - 0 = 4.0 s

Average rate of reaction = (0.01/4) = 0.0025 M/s

We could solve for the average rate of reaction expressed in moles Cl₂ consumed per liter per second

change in concentration of Cl₂ = -ΔC

= -(0.04 - 0.05) = 0.01 M

Time = Δt = 4 - 0 = 4.0 s

Average rate of reaction = (0.01/4) = 0.0025 M/s = 0.0025 mol/L.s

Hope this Helps!!!

8 0

4 years ago

his is the chemical formula for epinephrine (the main ingredient in adrenaline): C9H13O3N A biochemist has determined by measure

Len [333]

Answer:

3.67 moles of N

Explanation:

The epinephrine's chemical formula is: C₉H₁₃O₃N

We were told that a chemist found that in a mesaure of epinephrine, he found 33 moles of C

We must know that 9 moles of C are in 1 mol of C₉H₁₃O₃N so, let's make a rule of three:

If 9 moles of C are found in 1 mol of C₉H₁₃O₃N

Therefore 33 moles of C must be found in (33 .1) / 9 = 3.67 moles of C₉H₁₃O₃N

There is a second rule of three, then.

In 1 mol of C₉H₁₃O₃N we have 1 mol of N

Then, 3.67 moles C₉H₁₃O₃N must have (3.67 . 1) / 1 = 3.67 moles of N

Remember 1 mol of C₉H₁₃O₃N has 9 moles of C, 13 moles of H, 3 moles of O and 1 mol of N

5 0

3 years ago