I think it is 2nd law of motion
Answer:
As we have already discussed, reactivity of alkali metals tends to increase as you go down the group. Therefore, sodium is less reactive with water than is potassium, likewise with the alkaline metals; calcium is more reactive than magnesium
The correct answer to this question is that the length of 14 is it’s half Which would be 7
The energy released in nuclear reactions are far larger than that released in chemical reactions due to the release of nuclear energy from the nucleus.
<h3>Why is the energy released in a reaction?</h3>
Energy is released in a reaction due to the breaking of bonds are well as formation of bonds.
The quantity of energy released in reactions differs according to the reaction type involved.
When compared to chemical reactions, the energy released in nuclear reactions are very much higher because of the changes that occurs in the nucleus of the atoms involving nuclear energy.
The energy, E released in nuclear reactions is given by the formula below:

where m is the mass of the substance and c is the speed of light.
Therefore, the energy released in nuclear reactions are far larger than that released in chemical reactions.
Learn more about nuclear reactions at: brainly.com/question/984564
The mass of pentane the student should weigh out is
The density of pentane is 0.626 gcm-3
To calculate the mass of pentane following expression is used,
(Density is defined as the mass divide by volume)
Density = mass / volume
mass of pentane = Density of pentane * Volume of pentane
mass of pentane = 0.626 gcm-3 * 45.0 mL
= 28.17 g
Here the unit of mass of pentane is g,
However the unit of density is gcm-3 and unit of volume is mL i.e. cm3
Hence, Mass = gcm-3 * cm3
Mass = g
The mass of pentane the student should weigh out is 28.17g
Learn more about Density on
brainly.com/question/1354972
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