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5. How many elements do we have in Octane?

jekas [21]

Answer:

2 elements

Explanation:

Octane is composed of carbon and hydrogen atoms.

3 0

3 years ago

A certain gas has a volume of 500.0 mL at 77.0°C and 600KPa. Calculate the temperature if the volume decreased to 400.0 mL and t

Jlenok [28]

Answer:

354.67K

Explanation:

Applying

P₁V₁/T₁ = P₂V₂/T₂................. Equation 1

Where Where P₁ = initial pressure, T₁ = Initial temperature, V₁ = Initial Volume, P₂ = Final pressure, V₂ = Final Volume, T₂ = Final Temperature.

From the question, we are ask to look for the final temperature,

Therefore we make T₂ the subject of the equation

T₂ = P₂V₂T₁/P₁V₁............. Equation 2

Given: P₁ = 600 kPa, V₁ = 500 mL, T₁ = 77 °C = (273+77) = 350 K, P₂ = 760 kPa, V₂ = 400.0 mL

Substitute these values into equation 2

T₂ = (760×400×350)/(600×500)

T₂ = 354.67 K

3 0

3 years ago

A double replacement reaction is a reaction in which one element replaces a similar element within a compound. (2 points)

emmainna [20.7K]

Answer:

False

Explanation:

youre welcome

3 0

3 years ago

A perfume bottle is dropped in the corner of a room. Tge odor of the perfume can be detected on the other side of the room. Whic

Illusion [34]

<h2>Answer:</h2>

The<u> diffusion </u>occurs in room.

<u>Oder molecules move from their highest concentration to lowest concentration.</u>

<h3>Explanation:</h3>

Diffusion is a process by which molecules move down their concentration gradient. The process does not require any membrane.

So corner with perfume has high concentration of odor molecules. Hence they move to other corner with low concentration of molecules.

8 0

3 years ago

Read 2 more answers

The chemical symbol of several elements are given below. Determine the atomic number of each element. Chemical Atomic Number Sym

spayn [35]

<u>Explanation:</u>

Atomic number is defined as the number of protons or electrons that are present in a neutral atom.

Atomic number = number of protons = number of electrons

Mass number is defined as the sum of number of protons and neutrons that are present in an atom.

Mass number = Number of protons + Number of neutrons

The isotopic representation of an atom is: $_Z^A\textrm{X}$

where,

Z = Atomic number of the atom

A = Mass number of the atom

X = Symbol of the atom

<u>For A:</u>

1) Fe

The atom given to us is iron. It is present in Group 8 and period 4 of the periodic table. The atomic number of iron is 26

2) Be

The atom given to us is beryllium. It is present in Group 2 and period 2 of the periodic table. The atomic number of beryllium is 4

3) Kr

The atom given to us is krypton. It is present in Group 18 and period 4 of the periodic table. The atomic number of iron is 36

<u>For B:</u>

1) $_{24}^{53}\textrm{Cr}$

Atomic number = Number of protons = Number of electrons = 24

Mass number = 53

Number of neutrons = 53 - 24 = 29

The number of protons, electrons and neutrons for the given element are 24, 24 and 29 respectively

2) $_{44}^{103}\textrm{Ru}$

Atomic number = Number of protons = Number of electrons = 44

Mass number = 103

Number of neutrons = 103 - 44 = 59

The number of protons, electrons and neutrons for the given element are 44, 44 and 59 respectively

3) $_{30}^{67}\textrm{Zn}$

Atomic number = Number of protons = Number of electrons = 30

Mass number = 67

Number of neutrons = 67 - 30 = 37

The number of protons, electrons and neutrons for the given element are 30, 30 and 37 respectively

<u>For C:</u>

1) Atomic number = 14; Mass number = 28

The element having atomic number '14' is Silicon

The isotopic symbol of the element is $_{14}^{28}\textrm{Si}$

The symbol of the element is 'Si'

2) Atomic number = 18; Mass number = 40

The element having atomic number '18' is Argon

The isotopic symbol of the element is $_{18}^{40}\textrm{Ar}$

The symbol of the element is 'Ar'

3) Atomic number = 19; Mass number = 39

The element having atomic number '19' is Potassium

The isotopic symbol of the element is $_{19}^{39}\textrm{K}$

The symbol of the element is 'K'

5 0

3 years ago