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2 years ago

A car's engine runs on gasoline. A scientist describes the engine to be about 12% efficient. What does this mean?

1 answer:

5 0

Efficiency is the estimation of output power by any machine. A 12% efficient engine has an output provided by the input energy of the engine. Thus, option D is correct.

<h3>What is efficiency?</h3>

Efficiency is defined as the energy given by the machine, engine, or any system by utilizing the input power or energy. It is given as,

η = Output ÷ Input × 100%

It is used to know the ability of the machine to transfer the input energy to an external amount of work. The engine with 12% efficiency is said to have produced energy by utilizing the provided 12% input.

Therefore, option D. the 12% of input power is used by the engine to produce the energy.

Learn more about efficiency here:

brainly.com/question/22739880

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Quiz <br> Explain why<br> Ice melts by heating

labwork [276]

By providing the heat to the ice th closely packed particles of it gain kinetic energy and move away from each other so it melts

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3 years ago

Caproic acid, responsible for the odor of dirty socks, is composed of C, H, and O atoms. Combustion of a 0.225-g sample of this

puteri [66]

Answer: Empirical formula = C3H6O

C6H1202---Molecular formula

Explanation:

we first find the masses of C, H and O contained in the sample

<u>mass of carbon </u>

Mass of CO2 = 0.512g

molar mass of carbon = 12g/mol

Molar mass CO2 = 12+ (16X2)=44g/mol

Mass C = 12/44x 0.512 = 0.1396g of carbon

<u>Mass Hydrogen </u>

mass of H2O= 0.209g

Molar mass H2O = 18g/mol

Molar mass Hydrogen = 1.0079g x 2 = 2.0158g since Hydrogen gas is diatomic

Mass H = 2.0158/18 X 0.209 = 0.0234g Hydrogen

Mass of Oxygen in the sample = overall mass of Sample - mass of hydrogen and oxgen=

0.225 - ( 0.1396 + 0.0234) = 0.062g Oxygen

A) T o find Empirical formula

1ST STEP-- Divide through by each relative atomic mass:

C = 0.1396/12 = 0.01163

H = 0.0234/1.0079 = 0.0232

O = 0.0619/16 = 0.00387

2nd step Divide by smallest answer

C = 0.01163/0.00387 = 2.0998 = 3

H = 0.0232/0.00387 = 5.99 = 6

O = 0.00387/0.00387=1

Empirical formula = C3H6O

B)To find molecular formula

Given that molar mass of caproic acid as 116g,

we will use our empirical formulae to find molecular formulae with the equation

(C3H6O)n= 116g/mol

12x3 + 1x6 + 1 x16= 58g/mol

58n= 116g/mol

n = 116/58= 2

= (C3H6O)2= C(3X2) H(6X2) O(1X2)

C6H1202--- MOLECULAR FORMULA

7 0

3 years ago

A 45.0L gas cylinder contains 988 He at 23 degrees C what is the pressure inside the cylinder

gregori [183]

Answer:

P = 133.4 atm

Explanation:

Given data:

Mass of helium = 988 g

Volume = 45.0 L

Temperature = 23°C (23+273= 296 K)

Pressure of cylinder = ?

Solution:

Number of moles of helium:

Number of moles = mass/ molar mass

Number of moles = 988 g/ 4 g/mol

Number of moles = 247 mol

Pressure:

PV = nRT

P = nRT/V

P = 247 mol × 0.0821. atm. L/mol. K × 296 K / 45 L

P = 6002.5 / 45 L

P = 133.4 atm

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3 years ago

For a substance to change phases, the amount of internal energy must change. Water exists in three phases: liquid, solid (ice),

vfiekz [6]

Answer:

Solid, liquid, gas

Explanation:

add thermal energy to solid and it becomes liquid, add thermal energy to liquid it becomes gas

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3 years ago

Read 2 more answers

The knowledge produced by science builds on old ideas and is constantly changing.

VikaD [51]

Yes it is always changing, as time moves on new technological advancements are made. This makes it possible for new ideas to be created. For example the depiction of an atom went through many stages throughout the years in order to find out our current final version. New scientists and new ideas can add on to older ones, making explanations that make more scientific sense.

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3 years ago