2.5 in scientific notation

Describe the development of the modern model of the atom.

umka21 [38]

Answer:

currently model of the atom shows an atom that is mostly empty space. In the center is a small nucleus made of protons and neutrons. The nucleus contains nearly all the mass of an atom. Surrounding the nucleus is a cloud-like region with electrons moving too fast and too unpredictably for us to know their location

Explanation:

3 0

3 years ago

Read 2 more answers

What are the 3 main points of the kinetic molecular theory of gases

tigry1 [53]

Answer:

No energy is gained or lost when molecules collide. The molecules in a gas take up a negligible (able to be ignored) amount of space in relation to the container they occupy. The molecules are in constant, linear motion.

Explanation:

Hope this helps!

5 0

3 years ago

Does icicles have cells

SOVA2 [1]

No icicles are water made up of atoms not cells

6 0

3 years ago

4. Arrange the following substances in order of increasing boiling point: CH3CH2OH, HOCH2CH2OH, CH3CH2Cl , and ClCH2CH2OH A. CH3

Studentka2010 [4]

Answer: Option (B) is the correct answer.

Explanation:

A molecules that will have more number of hydrogen bonding will has highest boiling point because to break the hydrogen bonds high heat needs to be provided.

So, in the molecule $HOCH_{2}CH_{2}OH$ there is presence of two alcoholic groups. Hence, it will have strongest hydrogen bonding as compared to the rest of molecules.

In the molecule $ClCH_{2}CH_{2}OH$ there will be hydrogen bonding and dipole-dipole interactions. Hence, it boiling point will be slightly less than $HOCH_{2}CH_{2}OH$ .

In the molecule $CH_{3}CH_{2}OH$ , there will be only hydrogen bonding. Hence, its boiling point is less than $ClCH_{2}CH_{2}OH$ .

In the molecule $CH_{3}CH_{2}Cl$ , there is no hydrogen bonding but there will be only dipole-dipole interactions. Hence, its boiling point will be the least.

Therefore, we can conclude that increasing order of boiling point will be as follows.

$CH_{3}CH_{2}Cl$ < $CH_{3}CH_{2}OH$ < $ClCH_{2}CH_{2}OH$ < $HOCH_{2}CH_{2}OH$

6 0

3 years ago

A 265-mL flask contains pure helium at a pressure of 751 torrs. A second flask with a volume of 465 mL contains pure argon at a

Nadya [2.5K]

Answer:

Total Pressure = 745.6 torr

Partial Pressure of He = 272.8 torr

Partial Pressure of Ar = 472.8 torr

Explanation:

Step 1: Data given

Volume of the flask helium = 265 mL

Pressure in the helium flask = 751 torr = 751/760 atm

Volume of the flask argon = 465 mL

Pressure in the argon flask = 727 torr = 727/760 atm

The total pressure exerted by a gaseous mixture is equal to the sum of the partial pressures of each individual component in a gas mixture.

Step 2: Calculate total volume

Total volume = 265 mL + 465 mL = 730 mL = 0.730 L

Step 3: Boyle's Law:

P1V1=P2V2

⇒ with P1 = total pressure gas exerts in its own flask

⇒ with V1 = volume of flask with stopcock valve closed

⇒ with P2 = partial pressure of gas exerts on total volume of both flasks when stopcock valve is opened

⇒ with V2 = total volume of both flasks with stopcock valve opened

Helium using Boyle's Law equation from above:

P1V1=P2V2

⇒ with P1 = Pressure of helium = 751 /760 = 0.98816 atm

⇒ with V1 = volume of helium = 0.265 L

⇒ with P2 = The new partial pressure of helium

⇒ with V2 = total volume = 0.730 L

(0.98816 atm)(0.265L)=P2(0.730L)

P2=0.359 atm

Argon using Boyle's Law equation from above:

P1V1=P2V2

⇒ with P1 = Pressure of argon = 727/760 = 0.95658 atm

⇒ with V1 = volume of argon = 0.465 L

⇒ with P2 = The new partial pressure of argon

⇒ with V2 = total volume = 0.730 L

(0.95658 atm)(0.465L)=P2(0.730L)

P2=0.609 atm

Step 4: Convert pressure in atm to torr

Pressure helium = 0.359 atm = 272.8 torr

Pressure argon = 0.609 atm = 472.8 torr

Step 5: Calculate Total pressure

Ptotal = P(He)+P(Ar)

⇒ Pt = total pressure of the gas mixture

⇒ P(He) = partial pressure of Helium

⇒ P(Ar) = partial pressure of Argon

Pt = 272.8 torr + 472.8 torr

Pt = 745.6 torr

Total Pressure = 745.6 torr

Partial Pressure of He = 272.8 torr

Partial Pressure of Ar = 472.8 torr

5 0

4 years ago