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3 years ago

What is the Molarity of a 2 liter solution containing 43.55 grams of K2504?

Chemistry

1 answer:

yaroslaw [1]3 years ago

5 0

Answer:

M = 0.125 M

Explanation:

Given data:

Molarity = ?

Volume of solution = 2 L

Mass of K₂SO₄ = 43.55 g

Solution;

Molarity is used to describe the concentration of solution. It tells how many moles are dissolve in per litter of solution.

Formula:

Molarity = number of moles of solute / L of solution

Number of moles of solute:

Number of moles = mass/molar mass

Number of moles = 43.55 g / 174.26 g/mol

Number of moles = 0.25 mol

Molarity:

M = 0.25 mol / 2 L

M = 0.125 M

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Which part of the atom is responsible for chemical bonding

Firdavs [7]

It states the fact, which we now know, that electrons are responsible for the chemical bonding. According to this theory, valency is the number of electrons present in the outermost energy shell of the atom. This energy shell is called valency shell.

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4 years ago

A student increases the temperature of a 556 cm3 balloon from 278 K to 308 K. Assuming constant pressure, what should the new vo

Mandarinka [93]

The answer is: [D]: " 417 cm³ " .
_____________________________________________________
Explanation: Use the formula:

V₁ /T₁= V₂ /T₂ ;

in which: V₁ = initial volume = 556 cm³ ;
                T₁ = initial temperature = 278 K ;
                V₂ = final ("new") temperature = 308 K
                T₂ = final ("new:) volume = ?

Solve for "V₂" ;

Since: V₁ /T₁= V₂ /T₂ ;

We can rearrange this "equation/formula" to isolate "V₂" on one side of the equation; and then we can plug in our know values to solve for "V₂" ;
_______________________________________________________
       V₁ /T₁= V₂ /T₂ ; Multiply EACH side of the equation by "T₂ " :

          → T₂ (V₁ /T₁) = T₂  (V₂ /T₂) ;
______________________________
to get:

↔ T₂  (V₂ /T₂) = T₂ (V₁ /T₁) ;

     → V₂ = T₂ (V₁ /T₁) ;
______________________________
Now, plug in our known values, to solve for "V₂" ;
______________________________
    → V₂ = T₂ (V₁ /T₁) ;
______________________________
    → V₂ = 308 K ( 556 cm³ /278 K) ;
             → The units of "K" cancel to "1" ; and we have:
________________________________________________________
    → V₂ = 308*( 556 cm³ / 278 ) = [(208 * 556) / 278 ] cm³ ;
Note: We will keep the units of volume as: "cm³ "; since all the answer choices given are in units of: "cm³ " ; {that is, "cubic centimeters"}.

   → [(208 * 556) / 278 ] cm³ = [ (115,648) / (278) ] cm³ ;

              → For the "(115,648)" ; round to "3 (three significant figures)" ;
                        → "(115,648)" → rounds to: "116,000" ;
____________________________________________________
              →      (116,000) / (278) = 417.2661870503597122 ;
                                 → round to 3 significant figures; → "417 cm³ " ;
                                               → which corresponds with "choice [D]".
______________________________________________________
The answer is: [D]: "417 cm³ " .
______________________________________________________

3 0

3 years ago

Calculate the root mean square velocity of nitrogen molecules at 25°c. a) 729 m/s b) 515 m/s c) 149 m/s d) 297 m/s

Elena L [17]

Answer:

root mean square velocity of nitrogen at 25°c is 515 m/s

correct option is b) 515 m/s

Explanation:

given data

temperature = 25°c = 25 + 273 = 298 K

to find out

root mean square velocity of nitrogen molecules

solution

we know that root mean square velocity of gas is Vrms = $\sqrt{\frac{3RT}{M}}$ .......................1

mass of gas = M

universal gas constant = R

temperature = T

and we know mass of nitrogen = 28 g = 28 × $10^{-3}$ kg

Vrms = $\sqrt{\frac{3RT}{M}}$

Vrms = $\sqrt{\frac{3(8.314)298}{28*10^{-3}}}$

Vrms = 515.22 m/s

root mean square velocity of nitrogen at 25°c is 515 m/s

correct option is b) 515 m/s

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3 years ago

cherries on a tree freeze at -2°. The weather forecast said that tonight's low is -5° C. The old farmer sprays down his trees wi

just olya [345]

Old wives tale

Explanation:

This is an old wives tale and not scientifically correct.

Water is liquid that is known to freeze at 0° C.

The boiling point of water is also 100° C.

If the farmer sprays the cherries on the tree with water, it suggests that they will freeze faster because water has high freezing point compared to that of the cherry.
This will not in any way protect the cherries on the tree.
To prevent the cherries from freezing, he should spray them with something that has lower freezing point.

learn more:

Freezing point brainly.com/question/11126965

#learnwithBrainly

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4 years ago

In the fusion reaction occurring in the Sun, how does the mass of helium atom formed compare to the mass of the hydrogen atoms?

sladkih [1.3K]

The nuclear fusion in our sun combines two hydrogen atoms (the smallest and lightest atoms) together to form one helium atom (a slightly larger atom). During the process some of the mass is converted into energy.

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4 years ago