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2 years ago

What is a chemical change?

Chemistry

1 answer:

iris [78.8K]2 years ago

4 0

Answer:

D. A reaction or change in a substance that results in a different substance

Explanation:

Chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances.

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Write the chemical symbol for the isotope of cobalt with 37 neutrons

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Answer:

64Co27

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3 years ago

the volume of a gas with a pressure of 1.2 atmospheres increases from 1 to 4 what is the final pressure of the gas assuming cons

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3 years ago

Some hormones enter cells via

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ANSWER: receptor-meditated endocytosis
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3 years ago

Why metals are denser than non - metals ? ...?

Solnce55 [7]

Because their molecules are more tightly packed. Massdensity = ---------- Volume
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3 years ago

What is the significance of "Er" in the diagram?

Drupady [299]

Answer:

The significance of "Er" in the diagram is :

B.) Threshold energy for reaction

Explanation:

Threshold energy : It is total amount of energy required by the reactant molecule to reach the transition state .

Activation energy : It is the excess energy absorbed by the molecules to reach the transition state.

Activation Energy = Threshold Energy - Average Kinetic Energy

This means Activation energy decreases on increasing kinetic energy

On increasing Temperature average kinetic energy of the molecule increases which reduces the activation energy and the reaction occur faster in that case.

Catalyst also reduces the Activation energy.

Er = Threshshold energy for reaction at 30 degree

Ea = Activation Energy

The given figure shows that the threshold energy decreases on increasing the temperature

Only the molecule having energy greater than Er can react to form product

3 0

3 years ago

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