How many Group 17 elements are in Period 3 of the Periodic Table? A) 1 B) 2 C) 3 D) 4

saul85 [17]

Any of the basic mechanical devices for applying a force, such as an inclined plane, wedge, or lever.

8 0

3 years ago

Calculate the volume in liters of a potassium iodide solution that contains of potassium iodide . Be sure your answer has the co

Anna11 [10]

Answer:

23.8 L

Explanation:

There is some info missing. I think this is the original question.

<em>Calculate the volume in liters of a 0.0380M potassium iodide solution that contains 150 g of potassium iodide. Be sure your answer has the correct number of significant digits.</em>

<em />

The molar mass of potassium iodide is 166.00 g/mol. The moles corresponding to 150 grams are:

150 g × (1 mol/166.00 g) = 0.904 mol

0.904 moles of potassium iodide are contained in an unknown volume of a 0.0380 mol/L potassium iodide solution. The volume is:

0.904 mol × (1 L/0.0380 mol) = 23.8 L

6 0

3 years ago

A 7.00-mL portion of 8.00 M stock solution is to be diluted to 0.800 M. What will be the final volume after dilution? Enter your

amm1812

Explanation:

The number of moles of solute present in liter of solution is defined as molarity.

Mathematically, Molarity = $\frac{\text{no. of moles}}{\text{Volume in liter}}$

Also, when number of moles are equal in a solution then the formula will be as follows.

$M_{1} \times V_{1} = M_{2} \times V_{2}$

It is given that $M_{1}$ is 8.00 M, $V_{1}$ is 7.00 mL, and $M_{2}$ is 0.80 M.

Hence, calculate the value of $V_{2}$ using above formula as follows.

$M_{1} \times V_{1} = M_{2} \times V_{2}$

$8.00 M \times 7.00 mL = 0.80 M \times V_{2}$

$V_{2} = \frac{56 M. mL}{0.80 M}$

= 70 ml

Thus, we can conclude that the volume after dilution is 70 ml.

7 0

3 years ago

I need help with both questions

a_sh-v [17]

Answer:

not sure about 6 but 7 should be c

Explanation:

..

6 0

3 years ago

What is the application of the emission spectra regarding elements?

malfutka [58]

The emission spectrum of a chemical element or chemical compound is the spectrum of frequencies of electromagnetic radiation emitted due to an atom or molecule making a transition from a high energy state to a lower energy state. The photon energy of the emitted photon is equal to the energy difference between the two states. There are many possible electron transitions for each atom, and each transition has a specific energy difference. This collection of different transitions, leading to different radiated wavelengths, make up an emission spectrum. Each element's emission spectrum is unique. Therefore, spectroscopy can be used to identify elements in matter of unknown composition. Similarly, the emission spectra of molecules can be used in chemical analysis of substances.

8 0

3 years ago