Please help!!!!! The question is in the answer..

DATE PAGE No. 25. calculate the temperature at which air possesses a density equal to that of hydrogen at Dºc. Density of a'r at

Gemiola [76]

Answer: what is your issue

Explanation:

7 0

2 years ago

After reviewing your answers to questions 2 and 4 above, would you define boiling point and melting point as a periodic table fa

Andru [333]

The periodic table, and its respective melting and boiling points. ... Chemistry.2 The student will investigate and understand that the placement of elements ... Families/groups ... As you analyze your graph, try to answer the following questions: ... period. How would you describe the trend in boiling point as the atomic number ...

8 0

3 years ago

Which scientific investigation describes a field study?

weqwewe [10]

Answer:

A. A scientist investigates a mouse's growth in nature by watching the animal.

A field study is a raw collection of data, typically in the natural habit of the organism; hence why an experiment taken in a lab isn't a field study.

7 0

2 years ago

49.9 ml of a 0.00292 m stock solution of a certain dye is ddiluted to 1.00 L. the diluted solution has an absorbance of 0.600. w

inna [77]

Complete Question

49.9 ml of a 0.00292 m stock solution of a certain dye is diluted to 1.00 L. the diluted solution has an absorbance of 0.600. what is the molar absorptivity coefficient of the dye

Answer:

The value is $\epsilon = 4118.1 \ M^{-1} cm^{-1}$

Explanation:

From the question we are told that

The volume of the stock solution is $V_1 = 49.9 mL = 0.0499 \ L$

The concentration of the stock solution is $C_1 = 0.00292 \ M$

The volume of the diluted solution is $V_2 = 1.00 \ L$

The absorbance is $A = 0.600$

Generally the from the titration equation we have that

$C_1 * V_1 = C_2 * V_2$

=> $0.00292 * 0.0499 = C_2 * 1$

=> $C_2 = 0.0001457 \ M$

Generally from Beer's law we have that

$A = \epsilon * l * C_2$

=> $\epsilon = \frac{A}{ l * C_2 }$

Here l is the length who value is 1 cm because the unit of molar absorptivity coefficient of the dye is $M^{-1} * cm^{-1}$

So

$\epsilon = \frac{0.600}{ 1 * 0.0001457 }$

=> $\epsilon = 4118.1 \ M^{-1} cm^{-1}$

4 0

2 years ago

How many moles of fe2o3 will be produced from 18.0 g of fe assuming o2 is available in excess

Advocard [28]

Answer:

0.161moles

Explanation:

Given parameters:

Mass of Fe = 18g

Oxygen gas is in excess

Unknown:

Number of moles of Fe₂O₃ produced = ?

Solution:

To start with, let us write a chemically balanced equation before proceeding to understand the nuances of this problem.

4Fe + 3O₂ → 2Fe₂O₃

In the equation above above, 4 mole of iron combined with 3 moles of oxygen gas to 2 moles of Fe₂O₃.

In solving this problem, we can identify that Fe is the limiting reactant since we have been told oxygen gas is in excess. The suggests that the extent to which the product is formed and the reaction proceeds hinges on the amount of Fe we have.

It is best to work from the given, or known reactant to the unknown

The known in this scenario is the mass of Fe. Let us find the number of moles of this specie;

Number of moles of Fe = $\frac{mass}{molar mass}$

Molar mass of Fe = 56g/mol

Number of moles = $\frac{18}{56}$ = 0.32mol

Using this known number of moles of Fe, we can relate it to that of the unknown amount of the product and obtain the number of moles.

4 moles of Fe produced 2 moles of Fe₂O₃

0.32 moles of Fe will produce $\frac{0.32 x 2}{4}$ = 0.161moles

8 0

3 years ago