1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
DiKsa [7]
3 years ago
15

To aid in the prevention of tooth decay, it is recommended that drinking water contains 0.900 ppm fluoride (F-). A) How many g o

f F- must be added to a cylindrical water reservoir having a diameter of 3.36x10^2 m and a depth of 21.80 m? B) How many grams of sodium fluoride, NaF, contain this much fluoride?
Chemistry
1 answer:
Romashka-Z-Leto [24]3 years ago
3 0

Answer:

a) <u>1.740 g</u> of F- must be added to a cylindrical water reservoir

b) Grams of sodium fluoride, NaF, that contain this much fluoride:

3.84 g

Explanation:

Step 1. calculate the volume of the tank:

Volume of cylinder =

\pi  r^{2}h ,

Here r = radius of the cylinder = d/2

h = depth = 21.80m

r=\frac{d}{2}

=\frac{3.36x10^{2}}{2}

= 168 m

Volume =

=\frac{22\times 168^{2}\times 21.80}{7}

=1.93\times 10^{6} m^{3}

2.Convert ppm to g/m3 and Solve for mass of F-

1ppm = 1g/m^{3}

0.9ppm = 0.9g/m^{3}

Because both ppm and g/m3 are same quantity .

g/m^{3} =\frac{mass\ of\ F-(g)}{Volume\ m^{3}}\times 10^{6}

0.9 =\frac{mass\ of\ F-}{1.93\times 10^{6} m^{3}}\times 10^{6}

mass\ of\ F- =1.740g

mass of F- required = 1.740 g

3. Apply <u>mole concept </u>to calculate grams of sodium fluoride produced

mass of 1 mole of F2 = 38 g

mass of 1 mole of NaF = 42 g

(from periodic table calculate molar mass)

2Na+F_{2}\rightarrow 2NaF

Here 1 mole of F2 produce = 2 mole of NaF

So,

38 g  of F2 produce = 2 x 42 g of NaF

38 g of F2 produce = 84 g of NaF

1 g of F2 produce = 84/38 g of NaF

1.74 g F2 produce =

\frac {84}{38}\times 1.74

1.74 g F2 produce = 3.84 g of NaF

3.84 g of NaF is produced

You might be interested in
How much would a 10 kg suitcase weigh on the surface of…? a. The Moon b. Mars c. Saturn d. Pluto
alukav5142 [94]

Answer:

Is this the full question

Explanation:

Reply or love the message so i can get a notification

8 0
2 years ago
You are required to prepare 500 ml of a 6.00 M solution of HNO3 from a stock solution of 12.0 M. Describe in detail how you woul
andriy [413]

Answer: 250 ml of stock solution with molarity of 12.0 M is measured using a pipette and 250 ml of water is added to volumetric flask of 500 ml to make the final volume of 500 ml.

Explanation:

According to the dilution law,

C_1V_1=C_2V_2

where,

C_1 = concentration of stock solution = 12.0 M

V_1 = volume of stock solution = ?

C_2 = concentration of diluted solution= 6.00 M

V_2 = volume of diluted acid solution = 500 ml

Putting in the values we get:

12.0\times V_1=6.00\times 500

V_1=250ml

Thus 250 ml of stock solution with molarity of 12.0 M is measured using a pipette and 250 ml of water is added to volumetric flask of 500 ml to make the final volume of 500 ml.

8 0
2 years ago
Describe the flow of blood to the human body, including through each of the four chambers of the heart. Explain how the blood ch
xeze [42]
Hey there,

The blood needs to flow at a great and constant speed. It can not flow very slow because that can be warning's of a heart attack because your blood is using alot of force and its trying to provide as much blood as possible to arrive at the heart in order for your body to live. This is why we should drink water because as we drink water, it helps our blood flow through out our body well and so that we ma not have any problem now and in the future.

~Jurgen 
3 0
3 years ago
Read 2 more answers
Which of the following best describes the relationship of solar UV radiation to the environment?
aliya0001 [1]
<span> UV radiation are high energy radiations and they are mutation causing agents so
</span>Mutagen <span> best describes the relationship of solar UV radiation to the environment
so option A is correct
hope it helps</span>
4 0
3 years ago
The number of moles of solute in 200.ml of a 0.500 m solution is
IrinaK [193]

Answer:

I believe the answer is 0.100.

Explanation:

Hope my answer has helped you!

8 0
3 years ago
Other questions:
  • Will give brainliest if you show work and have the right answer :)
    7·2 answers
  • Which equation agrees with the ideal gas law? mc005-1.jpg mc005-2.jpg mc005-3.jpg mc005-4.jpg
    6·2 answers
  • Why do you think properties of materials used would be considered a constraint?
    5·1 answer
  • What rock has a hardness of 4,and has a dull luster. What is it?
    7·1 answer
  • Calculate the number of C atoms in 11g of carbon dioxide
    7·1 answer
  • 1.
    8·1 answer
  • A student transfers a gas at STP from a 11.0 L tank to a 25.0 L tank. If the pressure
    15·2 answers
  • A local am radio station broadcasts at a wavelength of 349m, calculate the energy of the wavelength at which it is broadcasting?
    8·1 answer
  • Need help ASAP plz. Only gave 10 min
    11·1 answer
  • Use the drop-down menus to complete each statement.
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!