Which statements describe molecules? Check all that apply.

A lead mass is heated and placed in a foam cup calorimeter containing 40.0 mL of water at 17.0°C. The water reaches a temperatur

lbvjy [14]

Answer: 502 Joules

Explanation:

To calculate the mass of water, we use the equation:

$\text{Density of substance}=\frac{\text{Mass of substance}}{\text{Volume of substance}}$

Density of water = 1 g/mL

Volume of water = 40.0 mL

Putting values in above equation, we get:

$1g/mL=\frac{\text{Mass of water}}{40.0mL}\\\\\text{Mass of water}=(1g/mL\times 40.0mL)=40.0g$

When metal is dipped in water, the amount of heat released by lead will be equal to the amount of heat absorbed by water.

$Heat_{\text{absorbed}}=Heat_{\text{released}}$

The equation used to calculate heat released or absorbed follows:

$q=m\times c\times \Delta T$

q = heat absorbed by water

$m$ = mass of water = 40.0 g

$T_{final}$ = final temperature of water = 20.0°C

$T_{initial$ = initial temperature of water = 17.0°C

$c$ = specific heat of water= 4.186 J/g°C

Putting values in equation 1, we get:

$q=40.0\times 4.186\times (20.0-17.0)]$

$q=502J$

Hence, the joules of heat were re-leased by the lead is 502

5 0

3 years ago

How much heat is needed warm 65.34 g of water from 18.43 to 21.75

BaLLatris [955]

Given that

Mass of water = 65.34 g

Amount of heat = mass of water * specific heat (temperature change

)

= 65.34 g * 4.184 J / g-C ( 21.75-18.43 )C

= 907.63 J

= 0.908 KJ

And

1 cal = 4.186798 J

907.63 J * 1 cal / 4.186798 J =216.78 cal

Or0.218 kcal

5 0

3 years ago

The diagram below represents the rock cycle.

spayn [35]

Answer:

Heat and Pressure

Explanation:

4 0

3 years ago

If fluorine gas (F₂) occupies a volume of 45.5 L at a pressure of 850

pshichka [43]

Taking into account about the ideal gas law, the mass of fluorine gas is 63.2244 grams.

<h3>What is ideal gas law</h3>

An ideal gas is a theoretical gas that is considered to be composed of randomly moving point particles that do not interact with each other. Gases in general are ideal when they are at high temperatures and low pressures.

The pressure, P, the temperature, T, and the volume, V, of an ideal gas, are related by a simple formula called the ideal gas law:

P×V = n×R×T

where:

P is the gas pressure.
V is the volume that occupies.
T is its temperature. The universal constant of ideal gases R has the same value for all gaseous substances.
R is the ideal gas constant.
n is the number of moles of the gas.

<h3>Definition of molar mass</h3>

The molar mass of substance is a property defined as its mass per unit quantity of substance, in other words, molar mass is the amount of mass that a substance contains in one mole.

<h3>Mass of fluorine gas</h3>

In this case, you know:

P= 850 mmHg= 1.11842 atm (being 1 mmHg= 0.00131579 atm)
V= 45.5 L
T =100 °C= 373 K (being 0°C= 273 K)
R= 0.082 $\frac{atm L}{mol K}$
n= ?

Replacing in the ideal gas law:

1.11842 atm ×45.5 L = n×0.082 $\frac{atm L}{mol K}$ × 373 K

Solving:

n= (1.11842 atm ×45.5 L)÷ (0.082 $\frac{atm L}{mol K}$ × 373 K)

<u><em>n= 1.6638 moles</em></u>

The molar mass of F₂ is 38 g/mole. Then you can apply the folowing rule of three: If by definition of molar mass 1 mole of the compound contains 38 grams, 1.6638 moles of the compound contains how much mass?

$mass= \frac{1.6638 molesx38 grams}{1 mole}$

<u><em>mass= 63.2244 grams</em></u>

Finally, the mass of fluorine gas is 63.2244 grams.

Learn more about

the ideal gas law:

brainly.com/question/4147359

molar mass:

brainly.com/question/5216907

brainly.com/question/11209783

brainly.com/question/7132033

brainly.com/question/17249726

#SPJ1

7 0

2 years ago

6. What is true about Calcium (Ca)?

sasho [114]

Answer:

C. naturally uncombined with other elements.

Explanation: Calcium is a chemical element with the symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air.

8 0

3 years ago