Why do objects cool down

A state function represent?

jeyben [28]

Answer:

a property whose value does not depend on the path taken to reach that specific value.

Explanation:

5 0

3 years ago

I need help with 1,2,3, and 4

Schach [20]

Answer:

Problem 1: 1.85atm

Problem 2: 110mL

Problem 3: 290 mL

Problem 4: 1.14 atm

Explanation:

Problem 1

1. Data

a) P₁ = 3.25atm

b) V₁ = 755mL

c) P₂ = ?

d) V₂ = 1325 mL

r) T = 65ºC

2. Formula

Since the temeperature is constant you can use Boyle's law for idial gases:

$PV=constant\\\\P_1V_1=P_2V_2$

3. Solution

Solve, substitute and compute:

$P_1V_1=P_2V_2\\\\P_2=P_1V_1/V_2$

$P_2=3.25atm\times755mL/1325mL=1.85atm$

Problem 2

1. Data

a) V₁ = 125 mL

b) P₁ = 548mmHg

c) P₁ = 625mmHg

d) V₂ = ?

2. Formula

You assume that the temperature does not change, and then can use Boyl'es law again.

$P_1V_1=P_2V_2$

3. Solution

This time, solve for V₂:

$P_1V_1=P_2V_2\\\\V_2=P_1V_1/P_2$

Substitute and compute:

$V_2=548mmHg\times 125mL/625mmHg=109.6mL$

You must round to 3 significant figures:

$V_2=110mL$

Problem 3

1. Data

a) V₁ = 285mL

b) T₁ = 25ºC

c) V₂ = ?

d) T₂ = 35ºC

2. Formula

At constant pressure, Charle's law states that volume and temperature are inversely related:

$V/T=constant\\\\\\\dfrac{V_1}{T_1}=\dfrac{V_2}{T_2}$

The temperatures must be in absolute scale.

3. Solution

a) Convert the temperatures to kelvins:

T₁ = 25 + 273.15K = 298.15K

T₂ = 35 + 273.15K = 308.15K

b) Substitute in the formula, solve for V₂, and compute:

$\dfrac{V_1}{T_1`}=\dfrac{V_2}{T_2}\\\\\\\\\dfrac{285mL}{298.15K}=\dfrac{V_2}{308.15K}\\\\\\V_2=308.15K\times285mL/298.15K=294.6ml$

You must round to two significant figures: 290 ml

Problem 4

1. Data

a) P = 865mmHg

b) Convert to atm

2. Formula

You must use a conversion factor.

1 atm = 760 mmHg

Divide both sides by 760 mmHg

$\dfrac{1atm}{760mmHg}=\dfrac{760mmHg}{760mmHg}\\\\\\1=\dfrac{1atm}{760mmHg}$

3. Solution

Multiply 865 mmHg by the conversion factor:

$865mmHg\times \dfrac{1atm}{760mmHg}=1.14atm\leftarrow answer$

3 0

3 years ago

A substance undergoes a change. Which of the following indicates that the change was a chemical change?

hoa [83]

The answer is A. The substance changed shape.

There you go!

4 0

3 years ago

I need help can someone please do so?

larisa86 [58]

Answer:

0.296 J/g°C

Explanation:

Step 1:

Data obtained from the question.

Mass (M) =35g

Heat Absorbed (Q) = 1606 J

Initial temperature (T1) = 10°C

Final temperature (T2) = 165°C

Change in temperature (ΔT) = T2 – T1 = 165°C – 10°C = 155°C

Specific heat capacity (C) =..?

Step 2:

Determination of the specific heat capacity of iron.

Q = MCΔT

C = Q/MΔT

C = 1606 / (35 x 155)

C = 0.296 J/g°C

Therefore, the specific heat capacity of iron is 0.296 J/g°C

8 0

3 years ago

Balance each chemical equation. Hg2(C2H3O2)2(aq)+KCl(aq)→Hg2Cl2(s)+KC2H3O2(aq)

Ira Lisetskai [31]

Answer:

Explanation:

When potassium chloride reacts with lead acetate in aqueous medium, it gives white precipitate of lead chloride and potassium acetate in aqueous medium as a product.

As shown in chemical reaction given below:

4 0

2 years ago

Why do objects cool down​

Why do objects cool down