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
tino4ka555 [31]
3 years ago
15

What is the percent concentration of a sodium fluoride solution made by dissolving 65.4 grams of sodium fluoride in 125.1 grams

of water?
Chemistry
1 answer:
Grace [21]3 years ago
6 0

Answer:

34.33 %.

Explanation:

  • To calculate the mass percent or weight percent of a solution, you must divide the mass of the solute by the mass of the solution (both the solute and the solvent together) and then multiply by 100 to change it into percent.

<em>W% = [(W of solute NaF)/(W of solution)] x 100.</em>

W of solute NaF = 65.4 g.

W of solution = W of solute NaF + W of water = 65.4 g + 125.1 g = 190.5 g.

∴ W% = [(W of solute NaF)/(W of solution)] x 100 = [(65.4 g)/(190.5 g)] x 100 = 34.33 %.

You might be interested in
Pressure gauge at the top of a vertical oil well registers 140 bars. The oil well is 6000 m deep and filled with natural gas dow
andreyandreev [35.5K]

Explanation:

(a)  The given data is as follows.

              Pressure on top (P_{o}) = 140 bar = 1.4 \times 10^{7} Pa       (as 1 bar = 10^{5})

              Temperature = 15^{o}C = (15 + 273) K = 288 K

         Density of gas = \frac{PM}{ZRT}

                \frac{dP}{dZ} = \rho \times g

               \frac{dP}{dZ} = \int \frac{PM}{ZRT}

                \int_{P_{o}}^{P_{1}} \frac{dP}{dZ} = \frac{Mg}{ZRT} \int_{0}^{4700} dZ

           ln (\frac{P_{1}}{P_{o}}) = \frac{18.9 \times 10^{-3} \times 9.81 \times 4700 m}{0.80 \times 8.314 J/mol K \times 288 K}

                              = 0.4548

                     P_{1} = P_{o} \times e^{0.4548}

                                 = 1.4 \times 10^{7} Pa \times 1.5797

                                 = 2.206 \times 10^{7} Pa

Hence, pressure at the natural gas-oil interface is 2.206 \times 10^{7} Pa.

(b)   At the bottom of the tank,

                 P_{2} = P_{1}  + \rho \times g \times h

                             = 2.206 \times 10^{7} Pa + 700 \times 9.81 \times (6000 - 4700)[/tex]

                             = 309.8 \times 10^{5} Pa

                             = 309.8 bar

Hence, at the bottom of the well at 15^{o}C pressure is 309.8 bar.

6 0
4 years ago
For a lake in Michigan, researchers have determined that largemouth bass feed on smaller fish, which in turn feed on zooplankton
allsm [11]

Answer:

the expected decline in largemouth bass is 3,000 kg.

Option d) 3,000 kg is the correct answer.

Explanation:

Given the data in the question;

In 2016, there was 600,000 kg of zooplankton in the lake.

In 2017, an accidental runoff of insecticide near the lake caused a 50 percent decline of the zooplankton population in the lake.

Now,

The remaining mass of zooplankton  after the 50% decline will be;

⇒ 600,000 kg zooplankton  × 50%

⇒ 600,000 × 50/100

⇒ 300,000 kg of zooplankton

Now, with 10 percent trophic efficiency;  smaller fish directly feed on zooplankton; decline in smaller fish mass will be;

⇒ 300,000 kg × 10%

⇒ 300,000 × 10/100

⇒  30000 kg

Finally, with 10 percent trophic efficiency, largemouth bash directly feed on smaller fish, so the expected decline in mass of largemouth bash will be;

⇒ 30000 kg × 10%

⇒ 30000 kg × 10/100

⇒ 3,000 kg

Therefore, the expected decline in largemouth bass is 3,000 kg.

Option d) 3,000 kg is the correct answer.

7 0
3 years ago
If 45.6 g of Fe2O3 reacts with excess water, how much heat is required?
tangare [24]

Explanation:

I

have not yet learnt chemistry so sorry

8 0
3 years ago
Read 2 more answers
In which location of the digestive system will you find both physical AND chemical digestion?
d1i1m1o1n [39]

Answer:

The stomach

Explanation:

In the stomach, physical digestion occurs because of peristaltic contractions (wave like contraction in the lean muscle) and chemical digestion occurs because of stomach acid, hydrochloric acid, breaking down your food.

5 0
3 years ago
Which scientist developed the first model of the atom that showed the structure of the inside of an atom
Eduardwww [97]

Answer:

Which scientist developed the first model of the atom that showed the structure of the inside of an atom

Ernest Rutherford

8 0
3 years ago
Other questions:
  • What is the purpose of taller emissions stacks in industrial settings? a) They are intended to release particulates where there
    11·2 answers
  • What mass of Al contains the same number of atoms as 33.5g of Au
    8·1 answer
  • I'm not sure on the answer for this question
    6·1 answer
  • What is the electron dot structure for beryllium and oxygen when they combine into a compound
    7·1 answer
  • Y7EICqeuL helppp meeee
    5·1 answer
  • Hey what's the value of pi till<br>5 digits after decimal​
    14·2 answers
  • Which star is the dimmest HELP PLEASE
    14·2 answers
  • 20)
    15·1 answer
  • What are the only elements that exist in nature as uncombined
    13·1 answer
  • What is the answer to this ?
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!