Assuming fixed shape when heated?

An alloy is made up of more than one type of what?

pychu [463]

More than one type of metallic elements.

4 0

3 years ago

A student weighs an empty flask and stopper and finds the mass to be 55.844 g. She then adds about 5 mL of an unknown liquid and

Oduvanchick [21]

Answer :

(a) The pressure of the vapor in the flask in atm is, 0.989 atm

(b) The temperature of the vapor in the flask in Kelvin is, 372.7 K

The volume of the flask in liters is, 0.2481 L

(c) The mass of vapor present in the flask was, 0.257 g

(d) The number of moles of vapor present are 0.00802 mole.

(e) The mass of one mole of vapor is 32.0 g/mole

Explanation : Given,

Mass of empty flask and stopper = 55.844 g

Volume of liquid = 5 mL

Temperature = $99.7^oC$

Mass of flask and condensed vapor = 56.101 g

Volume of flask = 248.1 mL

Barometric pressure in the laboratory = 752 mmHg

(a) First we have to determine the pressure of the vapor in the flask in atm.

Pressure of the vapor in the flask = Barometric pressure in the laboratory = 752 mmHg

Conversion used :

$1atm=760mmHg$

or,

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

As, $1mmHg=\frac{1}{760}atm$

So, $752mmHg=\frac{752mmHg}{1mmHg}\times \frac{1}{760}atm=0.989atm$

Thus, the pressure of the vapor in the flask in atm is, 0.989 atm

(b) Now we have to determine the temperature of the vapor in the flask in Kelvin.

Conversion used :

$K=273+^oC$

As, $K=273+^oC$

So, $K=273+99.7=372.7$

Thus, the temperature of the vapor in the flask in Kelvin is, 372.7 K

Now we have to determine the volume of the flask in liters.

Conversion used :

1 L = 1000 mL

or,

1 mL = 0.001 L

As, 1 mL = 0.001 L

So, 248.1 mL = 248.1 × 0.001 L = 0.2481 L

Thus, the volume of the flask in liters is, 0.2481 L

(c) Now we have to determine the mass of vapor that was present in the flask.

Mass of flask and condensed vapor = 56.101 g

Mass of empty flask and stopper = 55.844 g

Mass of vapor in flask = Mass of flask and condensed vapor - Mass of empty flask and stopper

Mass of vapor in flask = 56.101 g - 55.844 g

Mass of vapor in flask = 0.257 g

Thus, the mass of vapor present in the flask was, 0.257 g

(d) Now we have to determine the number of moles of vapor present.

Using ideal gas equation:

PV = nRT

where,

P = Pressure of vapor = 0.989 atm

V = Volume of vapor = 0.2481 L

n = number of moles of vapor = ?

R = Gas constant = 0.0821 L.atm/mol.K

T = Temperature of vapor = 372.7 K

Putting values in above equation, we get:

$(0.989atm)\times 0.2481L=n\times (0.0821L.atm/mol.K)\times 372.7K\\\\n=0.00802mole$

Thus, the number of moles of vapor present are 0.00802 mole.

(e) Now we have to determine the mass of one mole of vapor.

$\text{Mass of one mole of vapor}=\frac{\text{Mass of vapor}}{\text{Moles of vapor}}$

$\text{Mass of one mole of vapor}=\frac{0.257g}{0.00802mole}=32.0g/mole$

Thus, the mass of one mole of vapor is 32.0 g/mole

8 0

3 years ago

When one atom of carbon reacts with two atoms of oxygen, they combine to form one molecule of carbon dioxide. How many atoms of

tankabanditka [31]

The equation is: C+O2=>CO2

Since we got 10 molecules of CO2 new balanced equation would be 10C+10O2=>10CO2

from this equation we can see that we have 10 molecules of oxygen, however ,we need to find atoms. There are 2 atoms in the oxygen molecule so we need to multiply 10 by 2 which gives us 20 atoms.

The answer: there are 20 atoms of oxygen

4 0

3 years ago

23) What is the volume of 2.454 x 1024 atoms of nitrogen gas at STP?

earnstyle [38]

Answer:

d) V = 91.3 L

Explanation:

Given data:

Volume of nitrogen = ?

Temperature = standard = 273.15 K

Pressure = standard = 1 atm

Number of atoms of nitrogen = 2.454×10²⁴ atoms

Solution:

First of all we will calculate the number of moles of nitrogen by using Avogadro number.

1 mole = 6.022×10²³ atoms

2.454×10²⁴ atoms × 1 mol / 6.022×10²³ atoms

0.407×10¹ mol

4.07 mol

Volume of nitrogen:

PV = nRT

1 atm × V = 4.07 mol ×0.0821 atm.L /mol.K ×273.15 K

V = 91.3 atm.L /1 atm

V = 91.3 L

3 0

3 years ago

Which of the following does NOT involve a change of state? a. pouring water into a vacuum-insulated bottle b. sublimation of dry

Elena L [17]

<h2> The correct option is (a).</h2>

Explanation:

There is no change of state in pouring water into a vacuum insulated bottle as the vacuum created inside the bottle only reduces the time limit for the transfer of heat by conduction and convection.
It helps the content filled in the bottle to be hot and cool for a longer time.

Hence, option (a) is correct.

Rest of the options (b), (c), (d), (e) is not correct because of the following reasons:

In the sublimation of dry ice, the dry ice (solid-state) is changed to the vapour form.
In the freezing of water, the liquid state is changed to solid-state.
During the vaporization of alcohol, the liquid state is changed to the vapour form.
During the melting of ice, the solid-state is changed to the liquid state.

6 0

3 years ago

Assuming fixed shape when heated?​

Assuming fixed shape when heated?