PO3−4 what's the formula name?

Calculate the change in energy when 75.0 grams of water drops from<br> 31.0C to 21.6.

zysi [14]

Answer: Step 1: Calculate qsur (the surrounding is

usually the water)

qsur = ? J

m = 75.0 g water

c = 4.184 J/g

oC

ΔT = (Tfinal- Tinitial)= (21.6 – 31.0) = -9.4 oC

qsur = m · c · (ΔT)

qsur = (75.0g) (4.184 J/g

oC) (-9.4 oC)

qsur = - 2949.72 J

First, using the information we know that we

must solve for qsur, which is the water. We know

the mass for water, 75.0g, the specific heat of

the water, 4.184 j/g

o

c, and the change in

temperature, 21.6-31.0 = -9.4 oC. Plugging it

into the equation, we solve for qsur.

Step 2: Calculate qsys qsys = - (qsur)

qsys = - (- 2949.72 J)

qsys = + 2949.72

In this case, the qsur is negative, which means

that the water lost energy. Where did it go? It

went to the system. Thus, the energy of the

system is negative, opposite, the energy of the

surrounding.

Step 3: Calculate moles of the substance

that is the system

Given: 12.8 g KCl

Mol system = (g system given)

(molar mass of system)

Mol system = (12.8 g KCl)

(39.10g + 35.45g)

Mol system = 12.8 g KCl

74.55 g

Mol system = 0.172

Here, we solve for the mol in the system by

using the molar mass of the material in the

system.

Step 4: Calculate ΔH ΔH = q sys .

Mol system

ΔH= + 2949.72 J

0.172 mol

ΔH= +17179.81 J/mol or +1.72 x 104

J/mol

i hope this helps

5 0

3 years ago

Read 2 more answers

If you placed a rubber duck on the surface of the water in the middle of the pot, in which direction would it go

jeka57 [31]

Answer:

it would go be in the middle where u put it

Explanation:

i hope this helps ^^

8 0

2 years ago

How was New York City able to clean to smog?

podryga [215]

By using electric carssss

3 0

4 years ago

A chemical equation is shown: C2H4 + O2 → CO2 + H2O According to the law of conservation of mass, how many atoms of oxygen exist

astraxan [27]

Answer:

6 oxygens on the product side

Explanation:

1) balance the equation:

C2H4 + 3O2 → 2CO2 + 2H2O

2) calculate the number of oxygens on the product side

2CO2=4

2H2O=2

6 0

3 years ago

A 5 L tank of oxygen with a pressure of 23 atm is moved from room temperature of 293 K to a storage freezer at 230 K. What is th

Sedbober [7]

Answer: The final pressure inside the tank will be B. 18.05 atm. Gay-Lussac's law is used to predict the changes in pressure or temperature of gases. According to this law, there is a direct relationship between pressure and temperature. As the temperature of gas increases, so, too, will the pressure increase and vice versa.

Further Explanation:

We use the mathematical expression of Gay-Lussac's law to find the final pressure in the tank:

$\frac{P_{initial}}{T_{initial}} \ = \frac{P_{final}}{T_{final}}$

It is very important to note that when using this equation, all temperatures must be expressed in Kelvin. The conversion from degree Celsius to Kelvin is:

$T \ (in \ K) \ = T \ (in \ deg.\ C) \ +\ 273.15$

In the problem, we are given the following information:

P(initial) = 23 atm

T(initial) = 293 K

P(final) = ?

T(final) = 230 K

Plugging in these values in the Gay-Lussac Equation, we get:

$\frac{23\ atm}{293 \ K} \ = \ \frac{P_{final}}{230\ K} \\P_{final} \ = \frac{(23 \ atm) \ (230 \ K)}{293 \ K}\\P_{final} \ = \ 18.05 \ atm$

The tank was moved from a hotter to a cooler place. At cooler temperatures, gas particles move slower and frequency and strength of their collisions with each other and the wall of the containers decrease. This leads to a decrease in the pressure. Thus, the pressure drops from 23 atm to 18.05 atm when the tank is inside the freezer.

Learn More:

Learn more about Charles' Law brainly.com/question/7259721
Learn more about Ideal Gas Law brainly.com/question/4147359
Learn More about Boyle's Law brainly.com/question/8511562

Keyword: Gas Pressure, Temperature, Gay-Lussac's Law

8 0

3 years ago