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STALIN [3.7K]
3 years ago
13

A(n) ____________________ is a group of two or more atoms that are held together by chemical bonds. *

Chemistry
1 answer:
Kryger [21]3 years ago
6 0

Answer:

A molecule is a group of two or more atoms that are held together by chemical bonds.

Explanation:

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Order the terms according to the path followed by oxygen during cellular respiration.​
MArishka [77]

Answer:

Outside air

Nose

Lungs

Bloodstream

Cell

Explanation:

We breathe in oxygen from the outside air in through our nose and it travels to our lungs. Inside our lungs, we have Avioli's that diffuse oxygen into our bloodstream and the bloodstream helps the oxygen travel into our cells.

Hope this helps :)

8 0
3 years ago
How much energy is required to vaporize 155 g of butane at its boiling point? the heat of vaporization for butane is 23.1 kj/mol
netineya [11]

The energy required to vaporize 155 g of butane at its boiling point: 61,723 kJ

<h3>Further explanation</h3>

Enthalpy is the amount of system heat at constant pressure.

The enthalpy is symbolized by H, while the change in enthalpy is the difference between the final enthalpy and the initial enthalpy symbolized by ΔH.

\large{\boxed{\boxed{\bold{\Delta H=H_{End}-H_{First}}}}

Delta H reaction (ΔH) is the amount of heat change between the system and its environment

(ΔH) can be positive (endothermic = requires heat) or negative (exothermic = releasing heat)

The standard unit is kilojoules (kJ)

The enthalpy change symbol (ΔH) is usually written behind the reaction equation.

Change in Standard Evaporation Enthalpy (ΔH vap) is a change in enthalpy at the evaporation of 1 mol liquid phase to the gas phase at its boiling point and standard pressure.

Examples of water evaporation:

 H₂O (l) ---> H₂O (g); ΔH vap = + 44kJ

The enthalpy of evaporation is positive because its energy is needed to break the attraction between molecules in a liquid

  • 155 g of butane

relative molecular mass of butane (C₄H₁₀) = 4.12 + 10.1 = 58 gram / mol

tex]\large{\boxed{mole\:=\:\frac{grams}{relative\:molecular\:mass}}}[/tex]

\large mole\:=\:\large \frac{155}{58}

mole = 2,672

Since the heat of vaporization for butane is 23.1 kj / mol, the energy needed to evaporate 2,672 moles of butane is:

23.1 kJ / mol x 2,672 mol = 61,723 kJ

<h3>Learn more</h3>

the heat of vaporization

brainly.com/question/11475740

The latent heat of vaporization

brainly.com/question/10555500

brainly.com/question/4176497

Keywords: the heat of vaporization, butane, mole, gram, exothermic, endothermic

4 0
3 years ago
Read 2 more answers
Suggest a way to keep a parked car cool on a sunny day/
Paraphin [41]

Answer:

Crack the windows

Explanation:

believe it or not, one researcher actually tested this back in the 1980s: A study in Pediatrics found that cracking the window 5 centimeters lowered the temperature in a car by about 28°F on a 98°F day .

7 0
2 years ago
describe an example of how humans used selective breeding in plants,and explain how that has benefited us
Crank
The plants give out oxygen so for us humans will live
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3 years ago
Please help will reward brainliest
dimaraw [331]
The answer is most definitely “A”
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