What are the two sources of energy for the Earth system?

Express the concentration of a 0.0320 M aqueous solution of fluoride, F−, in mass percentage and in parts per million (ppm). Ass

denis23 [38]

Answer:

607 ppm

Explanation:

In this case we can start with the ppm formula:

$ppm=\frac{mg~of~solute}{Litters~of~solution}$

If we have a solution of 0.0320 M, we can say that in 1 L we have 0.032 mol of $F^-$ , because the molarity formula is:

$M=\frac{mol}{L}$

In other words:

$0.0320~M=\frac{mol}{1~L}$

$mol=0.032~M*1~L=0.032~mol$

$1~L~of~Solution=0.0320~mol~of~solute$

If we use the atomic mass of $F$ (19 g/mol) we can convert from mol to g:

$0.0320~mol~F^-\frac{19~g~F^-}{1~mol~F^-}~=~0.607~g$

Now we can convert from g to mg (1 g= 1000 mg), so:

$0.607~g\frac{1000~mg}{1~g}=607~mg$

Finally we can divide by 1 L to find the ppm:

$ppm=\frac{607~mg}{1~L}=~607~ppm$

We will have a concentration of 607 ppm.

I hope it helps!

4 0

3 years ago

How many cm are equal to 1.45 m

Dima020 [189]

There are 145 centimeters in 1.45 meters.

8 0

2 years ago

Sodium metal reacts with water to produce hydrogen gas according to the following equation: 2Na(s) + 2H2O(l)2NaOH(aq) + H2(g) Th

Maru [420]

Answer:

Number of moles of sodium reacted = 0.707 moles

Explanation:

P(H₂) = P(T) – P(H₂O)

P(H₂) = 754 – 17.5 = 736.5 mm Hg

Use the ideal gas equation which

PV= nRT, where P is the pressure V is the volume, n is the number of moles R is the Gas Constant and T is temperature

Re- arrange to calculate the number of moles and using the data provided

n = P x V/R x T

n =736.5 x 8.77/62.36367 x (mmHg/mol K) x (20 + 273)

n = 0.35348668

n = 0.353 moles H₂

from the equation we know that

0.353 mole H₂ x 2mole Na/1mole H₂, So

0.353 x 2 = 0.707 mole Na

The number of moles of Sodium metal reacted were 0.707 moles.

3 0

2 years ago

Compare how entropy changes for the following two systems:

postnew [5]

System A undergoes an increase in entropy while system B undergoes a decrease in entropy.

Entropy is the degree of disorderliness of a system. The entropy of a system depends on the number of particles present in the system as well as the state of matter.

Entropy is increased when solid particles dissolve in water because more particles are produced thereby increasing the level of disorderliness in the system.

On the other hand, when vapor is condensed, the degree of disorderliness decreases as gases are converted to liquids.

Learn more: brainly.com/question/13146879

7 0

2 years ago

PLeaseee ITS Timedddd + BrainlIESTT

zmey [24]

Answer:

d. 12.3 grams of Al2O3

Explanation:

Based on the reaction:

4Al + 3O2 → 2Al2O3

Where 4 moles of Al reacts in excess of oxygen to produce 2 moles of aluminium oxide.

To solve this question we must find the moles of Aluminium. With these moles we can find the moles of aluminium oxide using the reaction:

Moles Al -Molar mass: 26.9815g/mol-

6.50g * (1mol / 26.9815g) = 0.241 moles Al

Mass Al₂O₃ -Molar mass: 101.96g/mol-

0.241 moles Al * (2 mol Al2O3 / 4 mol Al) = 0.120 moles Al2O3

0.120 moles Al2O3 * (101.96g / mol) =

12.3g of Al2O3 are produced.

Right answer is:

<h3>d. 12.3 grams of Al2O3 </h3>

8 0

2 years ago