A catalyst is a substance that decrease the activation energy needed to start a reaction.
Answer:
See Explanation
Explanation:
A substitution reaction means the replacement of one or more hydrogen atoms in an alkane by another atom or group. It does not introduce a double bond into the product. The product retains single bonds between the species present.
For instance;
CH4 + Cl2 -------> CH3Cl +HCl
is a substitution reaction
Dehydrogenation is the process of removing two hydrogen atoms from a saturated compound compound thereby yielding an unsaturated product.
E.g
C2H6 --------->C2H4 + H2
The key difference is that substitution reaction yields a saturated product while dehydrogenation yields an unsaturated product.
It is a stable isotope of lead metal. this isotope is of nonradioactive nature. The isotope occur naturally but can also be produced by fission reaction.
It appears as gray powder. With molecular weight of 207.9g/mol.
The boiling point is 1740° while the melting point is 327.4°
It is immediately available as typical and in custom packing of different grade of food, agriculture and pharmaceuticals.
it is used for biomedical and biological labelling. It is also used to measure pb (lead) level in blood by glycogen isotope dilution technique.
Each orbit surrounding an atom is allowed A LIMITED NUMBER OF ELECTRONS.
The number of orbit that an atom has is determined by its atomic number, the higher the atomic number the higher the number of orbit in the atom and each orbit has different energy level. Each orbit can only take fixed number of electron. The first shell can only take two electrons while the subsequent shells can only take eight electrons. When an orbit has taken the highest number of electron possible, the remaining electrons are moved to the next shell.