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4 years ago

Which of the following is a characteristic of a bird?

Chemistry

1 answer:

Elis [28]4 years ago

5 0

Answer:

Explanation:

Chickens are birds and they lay hard shelled eggs

Penguins are birds and lay hard shelled eggs

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A sample of gas occupies a volume of 73.7 mL. As it expands, it does 133.7 J of work on its surroundings at a constant pressure

katen-ka-za [31]

In thermodynamics, work performed by a system is the energy transferred by the system to its surroundings. It can be calculated by the expression:

W = PdV

Integrating,

We will have,

W = P(V2 - V1)
133.7 (1 litre-atm / 101.325 Joule) ( 760 Torr / atm ) = 783 (V2 - .0737 )
V2 = 1.35 L

Hope this answers the question. Have a nice day.

7 0

4 years ago

___Al+NaOH=>__Na3AlO3+H2

MaRussiya [10]

Explanation:

2Al + 2NaOH + 6H2O → 2Na[Al(OH)4] + 3H2

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8 0

3 years ago

0.5 kg or 0.5 lb which is a larger quantity

masha68 [24]

The correct answer is 0.5 kg If you whant me to explaine pls tell me

3 0

3 years ago

How many moles of H20 are needed to produce 1 mole of O2 in the following equation?

Alex787 [66]

2 moles is the answer

6 0

3 years ago

Which statements are true?

schepotkina [342]

Explanation:

Evaporation is defined as a process in which liquid state of water is changing into vapor state.

So, we need to break the bonds of liquid substance in order to convert it into vapor state. And, energy is absorbed for breaking of bonds which means that evaporation is an endothermic process.

Hence, the statement evaporation of water is an exothermic process is false.

When a hydrocarbon reacts with oxygen and leads to the formation of carbon dioxide and water then this type of reaction is known as combustion reaction.

A combustion reaction will always release heat energy. Hence, combustion reaction is exothermic in nature.

When energy is transferred as heat from the surroundings to the system then it means energy is being absorbed by the system. And, absorption of heat is an endothermic process for which $\Delta H$ is positive.

Whereas when energy is transferred from system to the surrounding then it means energy is released by the system which is an exothermic process.

Hence, for an exothermic process value of $\Delta H$ is negative.

Thus, we can conclude that statements which are true are as follows.

A combustion reaction is exothermic.

When energy is transferred as heat from the system to the surroundings, $\Delta H$ is negative.

For an endothermic reaction Deta H is positive.

5 0

3 years ago