The mass number is the summation of number of proton and neutron present in a nucleus of an atom. For the neutral atom the number of positive charge (number of proton) must be equal to the number of electrons. The number of electrons present in an atom is the atomic number of the atom. The standard way to express the mass number (a) and atomic number (m) of a atom (say X) is 
. Now for silicon number of electron or atomic number is 14. And the mass number (a) given 29. Thus the expression nucleus of silicon will be 
Answer:
Explanation has been given below
Explanation:
- Attachment of -Cl group at ortho position to acetamido group can be explained in terms of hydrogen bonding formation.
- A hydrogen bonding can be formed between proton attached with N atom in acetamido group and Cl atom at ortho position. This leads to a formation of a stable 5-membered ring structure.
- Hence ortho substitution by Cl is favorable process.
- There is no hydrogen bonding possible between Br and Cl atom in ortho position. Therefore Cl prefers para position to avoid steric hindrance.
- Structure of hydrogen bonded structure has been shown below.
Hello!
The Sun is the main source of providing energy for the satellites. There are solar panels on the satellites to get solar energy from the sun. The sun does provide solar energy and since it's the main source of energy for the satellites, that leaves you with your answer which is solar energy.
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