A likely application of a radioactive isotope with a short half-life such as Technetium-99 will be as a medical tracer. It will likely be used by a doctor to check the movement of substances within a person's body.
A radioactive isotope with such a long half-life like Rubidium-87 is likely used in the determination of the age of fossils and artifacts found by archaeologists.<span />
Answer:
The number of neutrons present in one atom of isotope of Silicon of mass 28 amu is<u> 14 neutrons</u>
Explanation:
Symbol of Si isotope

<u>Number of Neutron = Mass number - Atomic Number</u>
Mass number = Total number of protons and neutrons present in the nucleus of the atom.For Si = 28 amu
Atomic Number = Total number of Protons present in the nucleus.
Si = 14
Number of neutron = 24 - 14
= 14
heat is transferred from your hand to the ice cube
I will assume that the sign ? between the C and the CCH3 is a triple bond, and I will represent it by three vertical lines |||
So the reaction is:
<span>CH3CH2CH2CH2C ||| CCH3+2Br2 ---->
This is a typical reaction known as halogenation of alkines.
This is an addition reaction, i.e. the alkyne undergoes an addition of the Br2 (and it also happens with Cl2) to the triple bond to form a tetra halide.
.
Br Br
</span> | |
<span><span>CH3CH2CH2CH2C ||| CCH3+2Br2 ----> CH3 CH2 CH2 CH2 C - C</span> - CH3
| |
Br Br
</span>
Exothermic reaction is where there is release of energy during a reaction
The enthalpy of exothermic reaction is negative
The relation between energy of products, reactants and enthalpy of reaction is
Enthalpy of reaction = sum of enthalpy of formation of products - sum of enthalpy of formation of reactants
.
As enthalpy of reaction is negative, it means the enthalpy of products is less than the enthalpy of reactants so answer is
:
In an exothermic reaction the energy of the product is less than the energy of the reactants.