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4 years ago

How is a mole like a dozen?

Chemistry

2 answers:

nasty-shy [4]4 years ago

7 0

The mole is a unit for counting 6.02 1023 representative particles.

The dozen is used to count 12 items

12345 [234]4 years ago

3 0

Answer:

Answer in explanation.

Explanation:

The mole is a unit for counting 6.02 1023 representative particles. The dozen is used to count 12 items.

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What is the process that changes a substances from a liquid to a gas below the substance's boiling point?

Vera_Pavlovna [14]

This process is called evaporation as I believe

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4 years ago

The Big Bang produced all of the hydrogen that exists in our universe in a matter of minutes. Overtime, protons began to fuse wi

34kurt

Answer:

The atom will become a new element.

Explanation:

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3 years ago

1. Methane (CH4) combusts as shown in the equation below. If 3 moles of methane were used in the combustion, what would be the c

umka2103 [35]

Answer:

The change in enthalpy in the combustion of 3 moles of methane = -2406 kJ

Explanation:

<u>Step 1: </u>The balanced equation

CH4(g) + 2 O2(g) → CO2(g) + 2 H2O(g) ΔH = -802 kJ

<u>Step 2:</u> Given data

We notice that for 1 mole of methane (CH4), we need 2 moles of O2 to produce : 1 mole of CO2 and 2 moles of H20.

The enthalpy change of combustion, given here as Δ H , tells us how much heat is either absorbed or released by the combustion of <u>one mole</u> of a substance.

In this case: we notice that the combustion of 1 mole of methane gives off (because of the negative number), 802.3 kJ of heat.

<u>Step 3: </u>calculate the enthalpy change for 3 moles

The -802 kj is the enthalpy change for 1 mole

The change in enthalpy for 3 moles = 3* -802 kJ = -2406 kJ

The change in enthalpy in the combustion of 3 moles of methane = -2406 kJ

5 0

3 years ago

Selena is learning about how engineers choose metals for spacecraft. She discovers that spacecraft engineers often mix other met

Elena-2011 [213]

Ti is a transition metal.

<h3>Further explanation</h3>

Chemical symbol represent element or compound

The elements are arranged in the periodic system

1. 22

This is the atomic number of Titanium

The Atomic Number (Z) indicates the number of protons of an element

2. Ti

This is the symbol (chemical formula) of titanium

3. 47.90

This is the mass number of Titanium

Mass Number (A) = Number of protons + Number of Neutrons

Atomic Number (Z) = Mass Number (A) - Number of Neutrons

4. Titanium

This is the name of the element

To determine which group, alkaline, alkaline earth or transition it can be seen from the electron configuration

alkali and alkali earth : configuration from orbital 1s-7s

transition : configuration from orbital 3d-6d (Block d)

Electron configuration from Ti : [Ar] 3d²4s²

if we look at the configuration, then Ti is in the d block which is included in the transition metal

7 0

3 years ago

Benzene is a minor component of gasoline. The standard molar enthalpy of formation of benzene C7H16(l) is 48.95 kJ/mol. For the

Radda [10]

Answer:

-3135.47 kJ/mol

Explanation:

Step 1: Write the balanced equation

C₆H₆(l) + 7.5 O₂(g) ⇒ 6 CO₂(g) + 3 H₂O(g)

Step 2: Calculate the standard enthalpy change of the reaction (ΔH°r)

We will use the following expression.

ΔH°r = ∑np × ΔH°f(p) - ∑nr × ΔH°f(r)

where,

n: moles

ΔH°f: standard enthalpies of formation

p: products

r: reactants

ΔH°r = 6 mol × ΔH°f(CO₂(g)) + 3 mol × ΔH°f(H₂O(g)) - 1 mol × ΔH°f(C₆H₆(l)) - 7.5 mol × ΔH°f(O₂(g))

ΔH°r = 6 mol × (-393.51 kJ/mol) + 3 mol × (-241.82 kJ/mol) - 1 mol × (48.95 kJ/mol) - 7.5 mol × 0 kJ/mol

ΔH°r = -3135.47 kJ

Since this enthalpy change is for 1 mole of C₆H₆(l), we can express it as -3135.47 kJ/mol.

7 0

3 years ago